Repositório Institucional - Unifesp :: Navegando por Palavras-chave "Rat"

Navegando por Palavras-chave "Rat"

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Acute crack cocaine exposure induces genetic damage in multiple organs of rats
(Springer Heidelberg, 2016) Moretti, Eduardo Gregolin [UNIFESP]; Yujra, Veronica Quispe [UNIFESP]; Claudio, Samuel Rangel [UNIFESP]; Silva, Marcelo Jose Dias; Vilegas, Wagner; Pereira, Camilo Dias Seabra [UNIFESP]; De Oliveira, Flavia [UNIFESP]; Ribeiro, Daniel Araki [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)
Crack cocaine is a very toxic product derived from cocaine. The aim of this study was to evaluate genetic damage in multiple organs of rats following acute exposure to crack cocaine. A total of 20 Wistar rats were distributed into four groups (n = 5), as follows: 0, 4.5, 9, and 18 mg/kg body weight (b.w.) of crack cocaine administered by intraperitoneal route (i.p.). All animals were killed 24 h after intraperitoneal (i.p.) injection. The results showed that crack cocaine increased the number of micronucleated cells in bone marrow cells exposed to 18 mg/kg crack cocaine (p < 0.05). Peripheral blood and liver cells presented genetic damage as depicted by single cell gel (comet) assay at 9 and 18 mg/kg doses (p < 0.05). Immunohistochemistry data revealed significant increase in 8-hydroxy-20-deoxyguanosine (8-OHdG) immunoexpression in hepatocytes of animals exposed to crack cocaine at 9 and 18 mg/kg (p < 0.05) when compared with negative controls. Taken together, our results demonstrate that crack cocaine is able to induce genomic damage in multiple organs of Wistar rats.
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Acute Spinal Cord Injury Induces Genetic Damage in Multiple Organs of Rats
(Springer, 2012-08-01) Medalha, Carla Christina [UNIFESP]; Polesel, Fernanda Sato [UNIFESP]; Silva, Victor Hugo Pereira da [UNIFESP]; Martins, Renato Almeida [UNIFESP]; Pozzi, Renan [UNIFESP]; Ribeiro, Daniel Araki [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)
Spinal cord injury (SCI) is a devastating condition with important functional and psychological consequences. However, the underlying mechanisms by which these alterations occur are still not fully understood. the aim of this study was to analyze genomic instability in multiple organs in the acute phase of SCI by means of single cell gel (comet) assay. Rats were randomly distributed into two groups (n = 5): a SHAM and a SCI group killed 24 h after cord transection surgery. the results pointed out genetic damage in blood cells as depicted by the tail moment results. DNA breakage was also detected in liver and kidney cells after SCI. Taken together, our results suggest that SCI induces genomic damage in multiple organs of Wistar rats.
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Administration of lopinavir/ritonavir association during rat pregnancy: maternal and fetal effects
(I R O G Canada, Inc, 2013-01-01) Kulay Júnior, Luiz [UNIFESP]; Hagemann, Cristiane Cadore de Farias [UNIFESP]; Nakamura, Mary Uchiyama [UNIFESP]; Simoes, Ricardo Santos [UNIFESP]; Carvalho, Adelino Moreira de [UNIFESP]; Oliveira-Filho, Ricardo Martins [UNIFESP]; Espiridião, Silvia [UNIFESP]; Universidade Federal de São Paulo (UNIFESP); Universidade de São Paulo (USP); Jose do Rosario Vellano Univ; ABC Med Fdn FUABC
Purpose: To evaluate the effects of the association of lopinavir and ritonavir administered during the whole period of rat pregnancy. Methods: 62 Wistar rats of the EPM-1 variant weighing about 200 g were randomly divided into five groups: two controls (Ctr1 = stress control, n = 10; and Ctr2 = drug vehicle control, n = 10) and three experimental ones which were treated with an oral solution of lopinavir/ritonavir (Exp1 = 12.8/3.2 mg/kg b.w., n = 14; Exp2 = 38.4/9.6 mg/kg b.w., n = 14; Exp3 = 115.2/28.8 mg/kg b.w., n = 14) from 'day 0' up to the 20th day of pregnancy. Maternal body weight was recorded at the start of the experiment and on the 7th, 14th and 20th day thereafter. At term (20th day), upon laparotomy and hysterotomy, the rats were anesthetized and the amount of implantations, reabsorptions, living fetuses, placentae and intrauterine deaths were recorded. The collected fetuses and placentae were weighed and the concepts were examined under a stereoscope microscope for external malformations. Results: An apparent dose-unrelated lethal effect of the antiviral association on the pregnant rats was observed; notwithstanding, the body weight gain of the surviving rats had no changes, independent of the considered group. It was noted that the quantitative and qualitative intrauterine content of living term rats was indistinguishable from that of the controls. Conclusion: There was some degree of deleterious effects of the administration of the lopinavir/ritonavir association on pregnant rats; such effects eventually led to maternal death. However, neither the surviving rats showed toxicity nor did their concepts present any detectable change which could be related to the drug association.
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Alteration of purinergic P2X(4) and P2X(7) receptor expression in rats with temporal-lobe epilepsy induced by pilocarpine
(Elsevier B.V., 2009-02-01) Doná, Flávia [UNIFESP]; Ulrich, Henning; Persike, Daniele Suzete [UNIFESP]; Conceição, Isaltino Marcelo da [UNIFESP]; Blini, João Paulo [UNIFESP]; Cavalheiro, Esper Abrão [UNIFESP]; Silva Fernandes, Maria Jose [UNIFESP]; Universidade Federal de São Paulo (UNIFESP); Universidade de São Paulo (USP); Inst Butantan
Although ATP and P2X receptor activity have been lately associated with epilepsy, little is known regarding their exact roles in epileptogenesis. Temporal-lobe epilepsy (TLE) in rat was induced by pilocarpine in order to study changes of hippocampal P2X(2), P2X(4) and P2X(7) receptor expression during acute, latent or chronic phases of epilepsy. During acute and chronic phases increased P2X(7) receptor expression was principally observed in glial cells and glutamatergic nerve terminals, suggesting participation of this receptor in the activation of inflammatory and excitotoxic processes during epileptogenesis. No significant alterations of hippocampal P2X(2) and P2X(4) receptor expression was noted during the acute or latent phase when compared to the control group, indicating that these receptors are not directly involved with the initiation of epilepsy. However, the reduction of hippocampal P2X(4) receptor immunostaining in the chronic phase could reflect neuronal toss or decreased GABAergic signaling. (C) 2008 Elsevier B.V. All rights reserved.
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Analysis of the ki-67 index in the vaginal epithelium of castrated rats treated with tamoxifen
(Hospital clinicas, univ sao paulo, 2016) Nery-Aguiar, Afif Rieth; Aguiar, Yousef Qathaf; Conde Junior, Airton Mendes; Alencar, Airlane Pereira; Tavares, Cleciton Braga; Lopes-Costa, Pedro Vitor; Nazario, Afonso Celso [UNIFESP]; da Silva, Benedito Borges
OBJECTIVES: Vaginal atrophy and breast cancer are common conditions in postmenopausal women and tamoxifen is the standard endocrine treatment for hormone-sensitive tumors. The present study aimed to assess the effect of tamoxifen on Ki-67 protein expression in the vaginal epithelium of castrated rats. MATERIAL AND METHODS: Forty Wistar-Hannover adult, virgin, castrated rats were randomly divided into two groups, group I (control, n= 20) and group II (tamoxifen, n= 20), receiving 0.5 ml of propylene glycol and 250 mu g of tamoxifen diluted in 0.5 ml of propylene glycol, respectively, daily by gavage for 30 days. On the 31st day, the rats were euthanized and their vaginas were removed and fixed in 10% buffered formalin for the immunohistochemical study of Ki-67 protein expression. Data were analyzed by the Levene and Student's t tests (p<0.05). RESULTS: The mean index of Ki-67 expression in the rat vagina of groups I and II was 4.04 +/- 0.96 and 26.86 +/- 2.19, respectively (p<0.001). CONCLUSIONS: According to the results of the present study, tamoxifen, at the dose and treatment length used, induced a significant increase in the cell proliferation of the vaginal mucosa in castrated rats, as evaluated by Ki-67 protein expression.
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Androgen deprivation from pre-puberty to peripuberty interferes in proteins expression in pubertal and adult rat epididymis
(Elsevier B.V., 2013-07-01) Perobelli, Juliana Elaine; Patrão, Marilia Tavares Coutinho da Costa [UNIFESP]; Fernandez, Carla Dal Bianco; Sanabria, Marciana; Klinefelter, Gary R.; Avellar, Maria Christina Werneck [UNIFESP]; Kempinas, Wilma De Grava; Universidade Estadual de Campinas (UNICAMP); Universidade de São Paulo (USP); Universidade Federal de São Paulo (UNIFESP); UNESP Univ Estadual Paulista; United States Environm Protect Agcy
Few studies have focused on experimental testosterone deprivation in immature animals. Therefore, this study used sexually immature rats aiming to evaluate the testes and epididymis histology and proteins expression in these organs on PND50 and 75, after premature antiandrogen exposure, from PND21 to 44. Although the androgen deprivation from pre-puberty up to peripuberty did not alter the histological organization of the testes and epididymis either at puberty or at adulthood, the treatment impaired the expression of specific proteins in epididymal tissue at puberty and adulthood (androgen receptor, calmodulin, Rab11A). These changes may be related to impaired epididymal function, sperm quality and fertility capacity as observed in a previous study. Further studies are necessary to better investigate the molecular mechanisms involved in the impairment on reproductive competence of male rats after precocious hormonal injury. (c) 2013 Elsevier Inc. All rights reserved.
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Antimutagenic and antigenotoxic potential of grape juice concentrate in blood and liver of rats exposed to cadmium
(Springer, 2014-11-01) Moura, Carolina Foot Gomes de [UNIFESP]; Ribeiro, Flavia Andressa Pidone [UNIFESP]; Jesus, Gustavo Protasio Pacheco de [UNIFESP]; Silva, Victor Hugo Pereira da [UNIFESP]; Oshima, Celina Tizuko Fujiyama [UNIFESP]; Gollucke, Andrea Pittelli Boiago [UNIFESP]; Aguiar, Odair [UNIFESP]; Ribeiro, Daniel Araki [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)
The aim of this study was to evaluate the antimutagenic and antigenotoxic potential of grape juice concentrate in rodent organs exposed to cadmium chloride intoxication. A total of 15 Wistar rats were distributed into three groups (n=5), as follows: control group (CTRL; nontreated group), cadmium group (Cd), and cadmium-grape juice group (Cd+GJ). Exposed animals received intraperitoneal injection of cadmium chloride (1.2 mg/kg body weight) diluted in water and, after 15 days, Cd+GJ group received grape juice concentrate for 15 days, by gavage (0.8 mL, 1.18 mg of polyphenols kg(-1) day(-1)). Grape juice concentrate was able to decrease genotoxic effects induced by cadmium in peripheral blood and liver cells as depicted by single cell gel (comet) and micronucleus assays. A decrease for anti-8-hydroxy-20-deoxyguanosine (8OHdG) expression in hepatocytes of animals exposed to cadmium and treated with grape juice concentrate was also detected. Higher CuZn-SOD activity was observed in liver cells of the Cd+GJ group. No remarkable differences were seen regarding Mn-SOD activity among groups. Taken together, our results demonstrate that grape juice concentrate was able to exert antimutagenic and antigenotoxic activities in blood and liver cells of rats exposed to cadmium.
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Avaliação de genotoxicidade em múltiplos órgãos após compressão dos membros inferiores de ratos
(Universidade Federal de São Paulo (UNIFESP), 2014-10-14) Carneiro Neto, Nicola Jorge [UNIFESP]; Ribeiro, Daniel Araki [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)
Muscle injury is a common trauma in modern society as a result of mass disasters, muscle penetration by high velocity projectiles, blunt external trauma, or by prolonged immobilization in comatose patients after head trauma, alcoholic or drug overdose. However, the underlying mechanisms linking these alterations are still not fully understood, especially in acute phase. The aim of this study was to analyze genomic instability in multiple organs of rats after acute muscle injury by means of single cell gel (comet) assay. Rats were randomly distributed into three groups (n = 6 each group): control group and experimental groups: sacrificed 6 h as 12 h after muscle compression. The results indicate genetic damage in peripheral blood cells as depicted by tail moment results. DNA breakage was also detected in liver, lung and kidney cells after acute muscle injury for two times evaluated. Heart cells showed genetic damage after 12 h following muscle compression. Taken together, our results suggest that acute muscle injury induces genomic damage in multiple organs of Wistar rats. This novel finding offers new insights into the underlying mechanisms of the relationship between acute crush muscle injury and clinical manifestations that can occur during limb compression.
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Avaliação do potencial nutracêutico de extrato de cenoura roxa (daucus carota lSspSativus varAtrorubens alef) em múltiplos tecidos (sangue periférico, medula óssea e fígado) de ratos expostos ao cloreto de cádmio
(Universidade Federal de São Paulo (UNIFESP), 2016-03-31) Claudio, Saumel Rangel [UNIFESP]; Ribeiro, Daniel Araki [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)
The aim of this study was to investigate if purple carrot extract is able to protect against the noxious activities induced by cadmium exposure in multiple organs of rats. For this purpose, histopathological analysis, genotoxicity and oxidative status were investigated in this setting. A total of 20 Wistar rats weighing 250g on the average, and 8 weeks age were distributed into four groups (n=5), as follows: Control group (non-treated group, CTRL); Cadmium group (Cd) and Purple carrot extract groups at 400 mg/L or 800 mg/L. Histopathological analysis revealed that liver from animals treated with purple carrot extract improved tissue degeneration induced by cadmium intoxication. Genetic damage was reduced in blood and hepatocytes as depicted by comet and micronucleus assays in animals treated with purple carrot extract. SOD-CuZn and cytocrome C gene expression increased in groups treated with purple carrot extract. Purple carrot extract also reduced the 8OHdG levels and catalase expression in liver cells when compared to cadmium group. Taken together, our results demonstrate that purple carrot extract is able to protect against cadmium intoxication by means of reducing tissue regeneration, genotoxicity and oxidative stress in multiple organs of Wistar rats.
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Bronchial tree Architecture in Mammals of Diverse Body Mass
(Soc Chilena Anatomia, 2014-03-01) Monteiro, Adilson [UNIFESP]; Smith, Ricardo Luiz [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)
The anatomy of mammal's lung air space constitutes the bronchial tree which disposition is associated to air flux dynamics. Casts obtained from human, pig and rat lungs were studied to analyze possible differences of the bronchial tree architecture in mammals with diverse dimensions and posture. Air spaces were filled with polymers through trachea followed by acid corrosion. Tracheal and main bronchial division's diameters were measured to relate with body mass using allometry. The results revealed a dichotomic bronchial branching pattern in the human casts and a monopodial pattern in animals. In allometric relationship trachea was larger in rats, then pigs and lastly in humans, differences were statistically significant, the same occurs in right bronchus, as in the left bronchus there was no difference between rat and pig. The linear relationship between the human tracheal diameters was 1.2 times larger than the pig and 6.7 times larger than the rat; the pig tracheal diameter was 5.6 times larger than the rat. Quadruped position of the pig and rat is linked to a horizontal air way while the erect position, biped in human, correspond to a vertical air way. A big mammal shows less respiratory frequency than small mammals. Mammals with small, medium and high body mass allied to diverse posture and habits was compared revealing morphological differences in the bronchial trees as different allometric correlations between quadruped animals and human biped.
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Carbamazepine-exposure during gestation and lactation affects pubertal onset and spermatic parameters in male pubertal offspring
(Elsevier B.V., 2014-04-01) Andretta, Rhayza Roberta [UNIFESP]; Okada, Fatima Kazue [UNIFESP]; Paccola, Camila Cicconi [UNIFESP]; Stumpp, Taiza [UNIFESP]; Oliva, Samara Urban de [UNIFESP]; Miraglia, Sandra M. [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)
Carbamazepine (CBZ) is an anti-epileptic drug that acts on Leydig cells, affecting steroidogenesis and causes fetal malformation. the aim of this study was to investigate the effects of CBZ on male sexual maturation and other male parameters. Rat dams were treated with CBZ during pregnancy and breastfeeding. the anogenital distance (AGD) and the anogenital index (AGI) were obtained. Testicular descent and preputial separation were also evaluated. the offspring was euthanized at PND 41 and 63. the accessory glands were weighed and the testes were collected for histopathological, morphometric and sterological analyses. the numerical density of Leydig cells and hormone dosage were obtained. CBZ caused an increase of AGI and a delay of testicular descent and of preputial separation. CBZ also caused a decrease of testosterone level and of sperm count and an increase of abnormal sperm. These results indicate that CBZ delays puberty onset and affects steroidogenesis and sperm quality. (C) 2013 Elsevier Inc. All rights reserved.
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Cholinergic mechanisms in cocaine-induced genital reflexes in paradoxical sleep-deprived male rats
(Elsevier B.V., 2004-03-01) Andersen, Monica Levy [UNIFESP]; Papale, Ligia Assumpção [UNIFESP]; Tufik, Sergio [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)
In view of the fact that paradoxical sleep deprivation (PSD) modifies cocaine-induced genital reflexes (penile erection [PE] and ejaculation [EJ]), the aim of this study was to address the interaction of cholinergic agents with the action of cocaine on the genital reflexes of PSD male rats. After a 4-day period of PSD, each group was administered with cholinergic drugs 1 h prior to cocaine and was placed in observation cages. the administration of nicotine (0.12, 0.25, 0.5 and 1 mg/kg sc) reduced the frequency and number of animals displaying PE and increased PE latency. Pretreatment with mecamylamine (1.25, 5, 10 and 20 mg/kg sc) also significantly reduced PE frequency for all doses used. the percentage of rats showing EJ was significantly reduced in the group pretreated with 1 mg/kg of nicotine compared with the saline group. the administration of pilocarpine (1.25, 2.5, 5 and 10 mg/kg sc) and atropine (1.25, 5, 10 and 20 mg/kg sc) led to a reduction in the frequency of PE displayed by the rats. These data show that agonist and antagonist cholinergic drugs inhibit genital reflexes in PSD male rats injected with cocaine. the data also suggest that the stimulating action of cocaine in potentiating the sexual effects in PSD rats does not override the effects of the cholinergic mechanisms of sexual behavior. (C) 2004 Elsevier Inc. All rights reserved.
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Chronic action of association of zidovudine, lamivudine and ritonavir on pregnant rats. A biologic assay
(I R O G Canada, Inc, 2011-01-01) Wagner, A.; Nakamura, Mary Uchiyama [UNIFESP]; Simoes, Ricardo Santos [UNIFESP]; Oliveira-Filho, Ricardo Martins [UNIFESP]; Fontes, Tereza Maria Pereira [UNIFESP]; Carvalho, Luisa Patricia Fogarolli de [UNIFESP]; Espiridião, Silvia [UNIFESP]; Kulay Júnior, Luiz [UNIFESP]; Univ Jose do Rosario Vellano; Universidade Federal de São Paulo (UNIFESP); Universidade de São Paulo (USP)
Purpose: To evaluate at term the effects of a highly active antiretroviral (HAAR) drug association administered during the entire period of rat pregnancy. Methods: Three groups (n = 10 each) of adult pregnant rats were treated with an oral solution of HAAR (Exp 1 = 10/5/20 mg/kg b.w.; Exp 2 = 30/15/60 mg/kg b.w.; Exp 3 = 90/45/180 mg/kg b.w.) from day 0 up to the 20th day of pregnancy. A fourth group served as a control. At term (20th day) the rats were killed under deep anesthesia and the number of implantations, resorptions, living fetuses, placentae and intrauterine deaths were recorded. Results: The highest HAAR doses caused lower maternal weight gain, lower litter weights, and lower placental weights compared to the control group. Conclusions: HAAR during the entire period of rat pregnancy can reduce maternal body weight gain and lower term placental weight.
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Chronic lipoic acid treatment worsens energy imbalances in streptozotocin-induced diabetic rats
(Masson Editeur, 2009-04-01) Luz, J. [UNIFESP]; Zemdegs, J. C. S. [UNIFESP]; Amaral, L. S. G. [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)
Aim. - Our objective was to verify the energy balance in streptozotocin-induced diabetic rats chronically treated with lipoic acid (LA).Methods. - Diabetes was induced in rats by streptozotocin and the animals divided into four groups, comprising controls and diabetic rats, with each group receiving either daily intraperitoneal LA (30 mg/kg) or a buffer solution for 30 days. Body weight, food intake and stool and urine collections were recorded daily. On day 30, animals were sacrificed and the carcasses, faeces and urine collected and processed for calorimetric analysis. Blood glucose and insulin were also determined.Results. - All parameters of energy balance were affected by diabetes. LA treatment reduced weight gain, energy gain and gross food efficiency in both control and diabetic animals. However, the LA-treated animals tended to show higher energy expenditure than non-treated animals. Body composition was also affected by diabetes: fat content was impaired by LA treatment in both control and diabetic animals. the latter also showed increased glycaemia and decreased insulinaemia, but LA had no effect on these parameters.Conclusion. - Our results indicate that chronic treatment with LA aggravates energy imbalances in diabetic animals. Moreover, our data suggest the need to reconsider the use of LA as an adjuvant in the prevention and treatment of type 1 diabetes. (C) 2008 Elsevier Masson SAS. All rights reserved.
Acesso aberto (Open Access)
Comparação dos efeitos do laser de baixa potência e do ultrassom de baixa intensidade no processo de reparo ósseo em tíbia de rato
(Associação Brasileira de Pesquisa e Pós-Graduação em Fisioterapia, 2011-06-01) Oliveira, Poliani de; Sperandio, Evandro Fornias; Fernandes, Kelly Rossetti [UNIFESP]; Pastor, Fabio Alexandre Casarin; Nonaka, Keico Okino; Renno, Ana Claudia Muniz [UNIFESP]; Universidade Federal de São Carlos; UFSCar Departamento de Ciências Fisiológicas; Universidade Federal de São Paulo (UNIFESP)
BACKGROUND: Electrophysical agents such as Ultrasound (US) and low-level laser therapy (LLLT) have been increasingly used in physical therapy practice. Studies suggest that these devices are able to stimulate osteoblast proliferation and osteogenesis at the fracture site, resulting in a greater deposition of bone mass and speeding up the consolidation process. OBJECTIVE: The aim of this study was to analyze the effects of US and LLLT on the bone healing process, through biomechanical and histological analysis of the bone callus. METHODS: A total of 30 rats were randomly allocated into three groups: control group fracture without treatment (GC); fracture group treated with pulsed US, burst 1.5 MHz, 200us, 1KHz, 30 mW/cm² (GUS) and fracture group treated with laser 830nm, 100mW, 120J/cm² (GL). Bone defects were performed with a circular drill of 2mm in diameter in the animal's tibias. The treatments were carried out after surgery consisting of 7 applications every 48 hours. After 14 days the animals were sacrificed and the tibias were removed to perform the analysis, being the right tibia designated for biomechanical analysis, while the left tibia for histological analysis. RESULTS: The biomechanical analysis showed no statistically significant difference between biomechanical properties of the CG, CL and GUS. In morphometric analysis, both GUS and GL showed a significantly higher woven bone tissue area compared to the control group. However, when the two treatment modalities were compared, there were no statistical differences between them. CONCLUSION: Both devices used in this study were able to accelerate the bone healing process in rats.
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Comparative study of the effects of low-intensity pulsed ultra-sound and low level laser therapy on injured muscle repair
(Spie-int Soc Optical Engineering, 2011-01-01) Renno, Ana Claudia Muniz [UNIFESP]; Toma, Renata Luri [UNIFESP]; Feitosa, Suellen Maurin [UNIFESP]; Fernandes, Kelly Rossetti [UNIFESP]; Oliveira, Poliani de [UNIFESP]; Parizotto, Nivaldo Antonio [UNIFESP]; Ribeiro, Daniel Araki [UNIFESP]; Hamblin, Michael R.; Waynant, R. W.; Anders, J.; Universidade Federal de São Paulo (UNIFESP)
Muscle tissue is one of the most frequently affected by injury, whether during sports activities, or work activities. in this context, biochemical and biophysical resources have been studied to minimize the time of muscle regeneration. Among these, low intensity pulsed ultrasound (US) and low level laser therapy (LLLT) may be highlighted. Despite a series of evidences about the positive effects of these resources in the process of tissue regeneration, the cellular and morphological changes triggered by LLLT and U. S. are still largely unknown. Thus, the aim of this study was to investigate the effects of US and LLLT on muscle repair after cryolesion by means of histopathological analysis and immunohistochemistry for COX-2. A total of thirty five male Wistar rats were randomly distributed into 4 groups: intact control group; injured control group: muscle injured animals without any treatment; laser treated group: muscle injured animals treated with 830 nm laser and ultra-sound treated group: muscle injured animals treated with US. the treatments started 24 hours post-surgery and were performed during 6 sessions. the animals exposed to lasertherapy pointed out minor degenerative changes of muscle tissue. in the same way, exposure to ultrasound was able to reduce tissue injuries induced by cryolesion, but less intense than laser therapy. Strong COX-2 positive cells were found in rats submitted to cryolesion only, whereas COX-2 immunoexpression was lower in laser treated or ultrasound treated groups. in summary, this study reveals that both lasertherapy and ultrasound have positive effects on muscle repair in rats.
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Detection of Four Germ Cell Markers in Rats during Testis Morphogenesis: Differences and Similarities with Mice
(Karger, 2012-01-01) Encinas, Giselly [UNIFESP]; Zogbi, Camila [UNIFESP]; Stumpp, Taiza [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)
Germ cells are the only cells capable of transmitting genetic information from generation to generation. Germ cell development has been widely studied in different species. Among mammals, the mouse is the model used in the majority of studies on germ cell differentiation, sex determination and genetics. in the present study, we suggest that the rat is also a very important model for the investigation of the mechanisms of germ cell development. To study rat germ cell development and compare it with that of mouse, the germ cell markers germ cell nuclear antigen 1 (GCNA1), OCT4, mouse vasa homologue (MVH) and specific surface embryonic antigen 1 (SSEA1) were immunolabeled at different phases of embryonic and postnatal development. SSEA1 and GCNA1 were not detected in rat primordial germ cells and fetal gonocytes. GCNA1 was detected postnatally and was present only in leptotene, zygotene and early pachytene spermatocytes. On the other hand, in mice, these markers were detected in germ cells as soon as 11.5 days postcoitum (dpc). MVH was detected in migrating rat primordial germ cells as well as in those that have already colonized the gonads, whereas in mice, MVH is detected only in germ cells that have reached the gonads. in rats, OCT4-positive germ cells were detected from 13 to 17 dpc, but not at 19 dpc or in postnatal testes. This is in contrast with mice that show OCT4 labeling in both embryonic and adult testes. These data suggest that primordial germ cell development in rats and mice shows considerable differences and that the rat may also be an important model to study the embryonic development of germ cells. Copyright (C) 2011 S. Karger AG, Basel
Acesso aberto (Open Access)
Dinâmica da expressão de SOX2 durante a transição gonócito-espermatogônia em rato: possível relação com a emergência das espermatogônias tronco
(Universidade Federal de São Paulo (UNIFESP), 2015-08-27) Oliveira, Ticiana Volpato [UNIFESP]; Stumpp, Taiza [UNIFESP]; http://lattes.cnpq.br/1024329256080770; http://lattes.cnpq.br/8686935485016317; Universidade Federal de São Paulo (UNIFESP)
Investigar possíveis marcadores e função do SOX2 na fase de gonócito e no surgimento das espermatogônias tronco/indiferenciadas, além de definir a fase mais adequada para a obtenção de células tronco pluripotentes in vitro a partir das células germinativas masculinas. Métodos: Ratos com 1, 5, 8 e 25 dias pós-parto (dpp) tiveram os testículos analisados quanto à expressão dos genes e das proteínas SOX2, RB1, NANOG e PIWIL4. Resultados: A proteína SOX2 estava presente no citoplasma dos gonócitos nas idades de 1dpp e 5dpp e passou a ser detectada no núcleo das pré-espermatogônias aos 8dpp. A expressão da proteína SOX2 foi confirmada por Western Blot. Esses dados nos levam a sugerir que a proteína SOX2 talvez exerça função no processamento de RNAs. É possível que as pré-espermatogônias que apresentam marcação nuclear de SOX2 estejam destinadas a tornarem-se espermatogônias tronco. Conclusões: Visto que a detecção de SOX2 no núcleo das pré-espermatogônias coincide com a retomada da expressão da proteína OCT4 e dos gene Oct4 e Nanog, levanta-se a hipótese de que as pré-espermatogônias que expressam SOX2 nuclear e OCT4 são as melhores candidatas a se tornar espermatogônias tronco. Entretanto, os mecanismos envolvidos ainda precisam ser esclarecidos. Após 10 dias de co-cultura com células de Sertoli, as pré-espermatogônias de ratos com 8dpp geraram clusters.
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Down-regulation of Na+/K+-ATPase alpha(2) isoform in denervated rat vas deferens
(Elsevier B.V., 2000-09-15) Quintas, Luis Eduardo Menezes; Caricati-Neto, Afonso [UNIFESP]; Lafayette, Simone Sette Lopes [UNIFESP]; Jurkiewicz, Aron [UNIFESP]; Noel, François; Universidade Federal do Rio de Janeiro (UFRJ); Universidade Federal de São Paulo (UNIFESP)
In the rat vas deferens, an organ richly innervated by peripheral sympathetic neurons, we have demonstrated recently the expression of alpha(1) and alpha(2), but not alpha(3) isoforms of the a subunit of Na+/K+-ATPase (EC 3.6.1.37), a membrane-bound enzyme of vital function for living cells (Noel et al., Biochem Pharmacol 55: 1531-1535, 1998). in the present work, we characterized, qualitatively and quantitatively, Na+/K+-ATPase a isoforms in denervated rat vasa deferentia. [H-3]Ouabain binding at concentrations defined for high-affinity isoforms (alpha(2) and/or alpha(3)) detected only one class of specific binding sites in control (C) and denervated (D) vas deferens. Although the dissociation constant was similar for both groups [K-d = 138 +/- 14 nM (C) and 125 +/- 8 nM (D)], a marked decrease in density was observed after denervation [716 +/- 81 fmol(.)mg protein(-1) (C) and 445 +/- 34 fmol(.)mg protein(-1) (D), P < 0.05]. in addition, western blotting revealed that denervated vasa deferentia produce the alpha(1) and alpha(2) isoforms but not alpha(3), just as we reported for the controls previously (Noel et al., Biochem Pharmacol 55: 1531-1535, 1998). Densitometric analysis showed a decrease of the alpha(2) isoform by about 4094 in denervated organs, in very good agreement with what was shown with the [H-3]ouabain binding technique, but no significant change in oil isoform density. Truncated alpha(1) (alpha(1)T), an isoform suggested to exist in the guinea pig vas deferens, was not detected. Altogether, our results demonstrated that Na+/K+-ATPase alpha(2) is down-regulated after sympathetic denervation of the rat vas deferens. (C) 2000 Elsevier Science Inc.
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Early life stress decreases hippocampal BDNF content and exacerbates recognition memory deficits induced by repeated D-amphetamine exposure
(Elsevier B.V., 2011-10-10) Martins de Lima, Maria Noemia; Presti-Torres, Juliana; Vedana, Gustavo; Alcalde, Luisa Azambuja; Stertz, Laura; Fries, Gabriel Rodrigo; Roesler, Rafael; Andersen, Monica Levy [UNIFESP]; Quevedo, Joao; Kapczinski, Flavio; Schroeder, Nadja; Pontifical Catholic Univ; Univ Fed Rio Grande do Sul; Universidade Federal de São Paulo (UNIFESP); Univ So Santa Catarina; Natl Inst Translat Med INCT TM
Adverse experiences early in life may have profound influences on brain development, for example, determining alterations in response to psychostimulant drugs, an increased risk of developing a substance abuse disorder, and individual differences in the vulnerability to neuropsychiatric disorders later in life. Here, we investigated the effects of exposure to an early adverse life event, maternal deprivation, combined with repeated D-amphetamine (AMPH) administration in adulthood, on recognition memory and brain-derived neurotrophic factor (BDNF) levels in rats' brain and serum. Rats were exposed to one of the following maternal rearing conditions from postnatal days 1 to 14: non-deprived (ND) or deprived (D). in adulthood, both groups received injections of saline (SAL) or AMPH (2.0 mg/kg, i.p.) for 7 days. in Experiment I (performed 24 h after the last AMPH injection), AMPH induced long-term memory (LTM) impairments in ND and D groups. the D + AMPH group also presented short-term memory (STM) impairments, indicating that the effects of AMPH on memory were more pronounced when the animals where maternally deprived. the group exposed to D + SAL (SAL) showed only LTM impairments. in Experiment II (performed 8 days after the last injection), AMPH detrimental effects on memory persisted in ND and D groups. BDNF levels were decreased in the hippocampus of D + SAL rats. in conclusion, AMPH produces severe and persistent recognition memory impairments that were more pronounced when the animals were maternally deprived, suggesting that an early adverse life event may increase the vulnerability of cognitive function to exposure to a psychostimulant later in life. (C) 2011 Elsevier B.V. All rights reserved.

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