Navegando por Palavras-chave "Vas deferens"
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- ItemSomente MetadadadosAcute treatment with alcohol affects calcium signaling and contraction associated with apoptosis in vas deferens of periadolescent rats(Elsevier B.V., 2014-07-15) Verde, Luciana Ferreira [UNIFESP]; Lopes, Guiomar Silva [UNIFESP]; Miki Ihara, Silvia Saiuli [UNIFESP]; Jurkiewicz, Neide Hyppolito [UNIFESP]; Jurkiewicz, Aron [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)Our purpose was to verify if alcohol causes alterations on translocation of Ca2+ and tension induced by KCl or noradrenaline in vas deferens of periadolescent Wistar rats. A single dose of alcohol (i.p. 3.0 g/kg) or saline as control, was given 4 h before sacrifice. Longitudinal strips of prostatic portion were mounted in vitro for simultaneous measurements of intracellular Ca2+ and contractions. Fluorescence and tension were measured in strips loaded with the fluorescent dye fura-2. the mean values (+/- S.E.M.) of fluorescence ratios (F-340/380) evoked by KCl were significantly lower by about 70% after alcohol, in relation to control. It was about 50% lower when evoked by noradrenaline. in relation to tension, the respective mean values (+/- S.E.M.) were lower by about 60% in organs treated with KCl or by about 80% after noradrenaline. in some experiments, before noradrenaline contraction, the vas deferens was incubated with verapamil 10(-6) M for 30 min. in these experiments, contractions by noradrenaline in the presence of verapamil were decreased by about 70% by alcohol. Alcohol decreases cytosolic calcium and contractility after KCl and noradrenaline, as compared with controls. in addition, alcohol promoted damage of lumen structures. Prostatic portion showed no striking morphometric change after treatment but the number of TUNEL positive cells in muscular layer, basal lamina and lumen were increased by alcohol, indicating apoptosis, compared with controls. This investigation shows that alcohol treatment alters signaling of calcium which in turn compromises the contraction associated with a process of apoptosis of periadolescent rats. (C) 2014 Published by Elsevier B.V.
- ItemSomente MetadadadosAdaptive expression pattern of different proteins involved in cellular calcium homeostasis in denervated rat vas deferens(Elsevier B.V., 2005-11-21) Quintas, Luis Eduardo Menezes; Cunha, Valeria do Monti Nascimento; Scaramello, Christianne Bretas Vieira; Silva, Silva, Claudia Lucia Martins da; 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)The activity and protein expression of plasma membrane and sarco(endo)plasmic reticulum (Ca2+-Mg2+)ATPases and ryanodine receptors were investigated in surgically denervated rat vas deferens. the function of thapsigargin-sensitive but not thapsigargin-resistant (Ca2+-Mg2+) ATPase (from sarco(endo)plasmic reticulum and plasma membrane, respectively), evidenced by enzyme activity and Ca2+ uptake experiments, was significantly depressed by 30-50% when compared to innervated vas. Western blots showed that such reduction in sarco(endo)plasmic reticulum (Ca2+-Mg2+)ATPase performance was accompanied by a decrement of similar magnitude in sarco(endo)plasmic reticulum (Ca2+-Mg2+) ATPase type 2 protein expression, without any significant change in plasma membrane (Ca2+-Mg2+)ATPase expression. Finally, [3 H]ryanodine binding revealed that the density of ryanodine binding sites was reduced by 45% after denervation without modification in affinity. the present findings demonstrate that sarco(endo)plasmic reticulum proteins involved in intracellular calcium homeostasis are clearly down-regulated and brings further evidence of a modified calcium translocation in denervated rat vas deferens. (c) 2005 Elsevier B.V All rights reserved.
- ItemSomente MetadadadosA comparison of histamine effects on the sympathetic neurotransmission of testicular capsule and rat vas deferens(Springer, 2014-08-01) Silva Junior, Edilson Dantas da [UNIFESP]; Dantas Rodrigues, Juliano Quintella [UNIFESP]; Souza, Bruno Palmieri de [UNIFESP]; Caricati-Neto, Afonso [UNIFESP]; Jurkiewicz, Aron [UNIFESP]; Jurkiewicz, Neide H. [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)Histamine is an important modulatory agent of the sympathetic neurotransmission, but its exact action on the testicular capsule or rat vas deferens is not fully understood. the present study sought to further investigate the functional effects of histamine on the neuronal and exogenous noradrenaline-induced contraction of the testicular capsule and rat vas deferens as well as to evaluate the contractile properties of this drug. the testicular capsule or vas deferens from Wistar rats, 3-4 months old, weighing 300-400 g, was isolated and mounted in organ baths for functional experiments. the results indicated that the neuronally evoked contraction of the testicular capsule was affected by histamine (10(-10) to 10(-8) M) with participation of inhibitory (H-3 receptors) and excitatory (H-1 receptors) receptors. Histamine (10(-7) to 10(-4) M) modulated the field-stimulated vas deferens by excitatory (H-2 receptors) and inhibitory (H-1 receptors) receptors. Histamine was able to decrease the tonic response for noradrenaline-induced contractions with participation of H-1 receptors (testicular capsule) and H-3 receptors (vas deferens) followed by nitric oxide generation. At high concentration, histamine exerts contractile effects in both tissues. in the testicular capsule, the histamine-induced contractions were related to H-1 receptor activation followed by release of prostaglandins. in contrast, the contractile effects of histamine in the vas deferens were related to H-2 receptor activation followed by release of catecholamines from sympathetic nerve endings. Therefore, our results indicate that histamine induced several effects on the sympathetic neurotransmission of rat testicular capsule and vas deferens. These effects are dependent on the concentration used and with participation of multiple histamine receptors.
- ItemSomente MetadadadosDown-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.
- ItemSomente MetadadadosEfeito da ouabaína no ducto deferente de rato: sensibilização pela metoxamina e imidazolinas(Universidade Federal de São Paulo (UNIFESP), 1995) Wanderley, Almir Gonçalves [UNIFESP]; Jurkiewicz, Aron [UNIFESP]
- ItemSomente MetadadadosEfeito inibitório do clorobutanol no útero e ducto deferente de rato(Universidade Federal de São Paulo (UNIFESP), 1992) Wanderley, Almir Gonçalves [UNIFESP]; Jurkiewicz, Aron [UNIFESP]
- ItemSomente MetadadadosEffects of in vitro, acute and chronic treatment with fluoxetine on the sympathetic neurotransmission of rat vas deferens(Elsevier Science Bv, 2017) Pedroso, Shaista Poppe [UNIFESP]; de Souza, Bruno Palmieri [UNIFESP]; Jurkiewicz, Aron [UNIFESP]; Juriewicz, Neide H. [UNIFESP]; da Silva Junior, Edilson Dantas [UNIFESP]It is described that fluoxetine treatment is able to induce ejaculatory disorders. However, the exact mechanism is still not fully understood. Therefore, this study was carried out to further evaluate the anti-ejaculatory effects of fluoxetine, using different approaches (in vitro or in vivo treatments), on the sympathetic neurotransmission of the rat vas deferens. Vas deferens from male Wistar rats were used to check the in vitro effects of fluoxetine 10(-6) M, 3.10(-6) M or 10(-5) M. Animals were also acutely (20 mg/kg, i.p. 4 h or 24 h) or chronically (10 mg/kg, i.p., 30 days) treated with fluoxetine or drug-free vehicle. The vas deferens from non -treated and treated animals were isolated and mounted in an isolated organ bath for the study of the contractions induced by adrenergic agonists, tyramine, 5-HT, Ca2+ or electrical field stimulation. In vitro or acute treatment with fluoxetine decreased the contraction induced by agonists, Ca2+ or electrical field stimulation. The chronic treatment with fluoxetine decreased the contractions induced agonists, tyramine or Ca2+, but did not modify the contractions induced by electrical field stimulation. We have shown that in vitro or in vivo fluoxetine treatment is able to alter the sympathetic neurotransmission of the rat vas deferens which could be related to alterations in the calcium signalling. (C) 2016 Elsevier B.V. All rights reserved.
- ItemSomente MetadadadosFunctional effects of alcohol withdrawal syndrome on peripheral sympathetic neurotransmission in vas deferens of adult rats(Elsevier B.V., 2014-07-11) Bomfim, Guilherme Henrique Souza [UNIFESP]; Verde, Luciana Ferreira [UNIFESP]; Frussa-Filho, Roberto [UNIFESP]; Jurkiewicz, Aron [UNIFESP]; Jurkiewicz, Neide Hyppolito [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)Aims: Alcohol withdrawal syndrome (AWS) is characterized by a set of physiological modifications triggered by abrupt withdrawal and/or decreasing consumption of ethanol (EtOH), which May manifest 16-48 h after ceasing consumption. the relationship between the effects of AWS and central and peripheral sympathetic neurotransmission is unknown. This study investigates the possible mechanisms on the sympathetic system during periods of AWS.Main methods: Male Wistar rats were treated with EtOH (6-10 g/kg/day/v.o. 5 days). Subsequently, 1 h, 24 h, 48 h and 120 h after administration of the last dose of EtOH, the animals were sacrificed, and their vas deferens (VD) were removed to perform the following evaluations: (a) concentration-effect curves of sympathetic agonist; (b) activity of alpha(2)-adrenoreceptor; (c) function of voltage-dependent calcium channels (Cav); and (d) release of endogenous catecholamines measured in real time coupled to HPLC.Key findings: the results showed that the maximum effects of contraction were increased by agonists tested in at 24 h and 48 h EtOH withdrawal. the inhibitory affinity (pIC(50)) of guanfacine was decreased 24 h EtOH withdrawal. the function of Cav was also decreased as pIC50 values dropped 24 h and 48 h EtOH withdrawal. the release of catecholamines increased 48 h after EtOH withdrawal. It is suggested that AWS triggers hyperactivity in peripheral sympathetic neurotransmission.Significance: the mechanisms underlying hyperactivity are possibly explained by a failure of autoregulation from catecholamines released by alpha(2)-adrenoreceptors and/or an increase of Cav function, which may be potential targets to attenuate the symptoms of AWS at the peripheral level. (C) 2014 Published by Elsevier Inc.
- ItemAcesso aberto (Open Access)Influence of acute treatment with sibutramine on the sympathetic neurotransmission of the young rat vas deferens(Elsevier B.V., 2014-09-05) Souza, Bruno Palmieri de [UNIFESP]; Silva Junior, Edilson Dantas da [UNIFESP]; Jurkiewicz, Aron [UNIFESP]; Jurkiewicz, Neide Hyppolito [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)The effects of acute treatment with sibutramine on the peripheral sympathetic neurotransmission in vas deferens of young rats were still not evaluated. Therefore, we carried out this study in order to verify the effects of acute sibutramine treatment on the neuronal- and exogenous agonist-induced contractions of the young rat vas deferens. Young 45-day-old male Wistar rats were pretreated with sibutramine 6 mg/kg and after 4 h the vas deferens was used for experiment. the acute treatment with sibutramine was able to increase the potency (pD(2)) of noradrenaline and phenylephrine. Moreover, the efficacy (E) of noradrenaline was increased while the efficacy of serotonin and nicotine were decreased. the maximum effect induced by a single concentration of tyramine was diminished in the vas deferens from treated group. Moreover, the leftward shift of the noradrenaline curves promoted by uptake blockers (cocaine and corticosterone) and beta-adrenoceptor antagonist (propranolol) was reduced in the vas deferens of treated group. the initial phasic and secondary tonic components of the neuronal evoked contractions of vas deferens from treated group at the frequencies of 2 Hz were decreased. Moreover, only the initial phasic component at 5 Hz was diminished by the acute treatment with sibutramine. in conclusion, we showed that the acute treatment with sibutramine in young rats was able to affect the peripheral sympathetic nervous system by inhibition of noradrenaline uptake and reduction of the neuronal content of this neurotransmitter, leading to an enhancement of vas deferens sensitivity to noradrenaline. (C) 2014 Elsevier B.V. All rights reserved.
- ItemSomente MetadadadosNantenine blocks muscle contraction and Ca2+ transient induced by noradrenaline and K+ in rat vas deferens(Elsevier B.V., 2003-05-30) Ribeiro, R. D.; Garcez-do-Carmo, Lucia [UNIFESP]; Vladimirova, I; Jurkiewicz, N. H.; Jurkiewicz, A.; Universidade Federal de São Paulo (UNIFESP)The effect of nantenine, an aporphine alkaloid isolated from Ocotea macrophylla H.B.K., was studied on contractions and Ca2+ translocation induced by noradrenaline, Ca2+, or K+ in the isolated rat vas deferens from reserpinized animals. Concentration-response curves of calcium chloride (CaCl2) were performed in the vas deferens, in a Ca2+-free nutrient solution, using potassium chloride (KCl, 80 mM) as a depolarizing agent. in these conditions, nantenine (2.35 X 10(-4) and 4.7 x 10(-4) M) significantly reduced the maximum contractions (E-max) of Ca2+ (IC50 = 2.6 x 10(-4) M) and noradrenaline (IC50 = 2.9 x 10(-4) M). the contractile responses were totally recovered after the withdrawal of nantenine. in addition, experiments performed to measure simultaneously the contraction and the increase of intracellular Ca2+ induced by noradrenaline (10(-5) M) or KCl (80 mM) showed that nantenine (2.35 x 10(-4) and 4.7 x 10(-4) M) significantly decreased both effects. the results suggest that a reversible block of Ca2+ entry could be involved on the non-competitive-like antagonism of nantenine in rat vas deferens. (C) 2003 Elsevier Science B.V. All rights reserved.
- ItemAcesso aberto (Open Access)NF-kB overexpression and decreased immunoexpression of AR in the muscular layer is related to structural damages and apoptosis in cimetidine-treated rat vas deferens(Biomed Central Ltd, 2013-04-09) Koshimizu, Juliana Y.; Beltrame, Flavia L. [UNIFESP]; Pizzol, Jose P. de; Cerri, Paulo S.; Caneguim, Breno H.; Sasso-Cerri, Estela; UNESP; Universidade Federal de São Paulo (UNIFESP)Background: Cimetidine, histamine H-2 receptors antagonist, has caused adverse effects on the male hormones and reproductive tract due to its antiandrogenic effect. in the testes, peritubular myoid cells and muscle vascular cells death has been associated to seminiferous tubules and testicular microvascularization damages, respectively. Either androgen or histamine H-2 receptors have been detected in the mucosa and smooth muscular layer of vas deferens. Thus, the effect of cimetidine on this androgen and histamine-dependent muscular duct was morphologically evaluated.Methods: the animals from cimetidine group (CMTG; n=5) received intraperitoneal injections of 100 mg/kg b.w. of cimetidine for 50 days; the control group (CG) received saline solution. the distal portions of vas deferens were fixed in formaldehyde and embedded in paraffin. Masson's trichrome-stained sections were subjected to morphological and the following morphometrical analyzes: epithelial perimeter and area of the smooth muscular layer. TUNEL (Terminal deoxynucleotidyl-transferase mediated dUTP Nick End Labeling) method, NF-kB (nuclear factor kappa B) and AR (androgen receptors) immunohistochemical detection were also carried out. the birefringent collagen of the muscular layer was quantified in picrosirius red-stained sections under polarized light. the muscular layer was also evaluated under Transmission Electron Microscopy (TEM).Results: in CMTG, the mucosa of vas deferens was intensely folded; the epithelial cells showed numerous pyknotic nuclei and the epithelial perimeter and the area of the muscular layer decreased significantly. Numerous TUNEL-labeled nuclei were found either in the epithelial cells, mainly basal cells, or in the smooth muscle cells which also showed typical features of apoptosis under TEM. While an enhanced NF-kB immunoexpression was found in the cytoplasm of muscle cells, a weak AR immunolabeling was detected in these cells. in CMTG, no significant difference was observed in the birefringent collagen content of the muscular layer in comparison to CG.Conclusions: Cimetidine induces significant damages in the epithelium; a possible antiandrogenic effect on the basal cells turnover should be considered. the cimetidine-induced muscle cells apoptosis confirms the susceptibility of these cells to this drug. the parallelism between enhanced cytoplasmic NF-kB immunolabeling in the damaged muscular tissue and muscle cell apoptosis suggests that this drug may avoid the translocation of NF-kB to the nucleus and interfere in the control of NF-kB-mediated smooth muscle cell apoptosis. the decreased immunoexpression of ARs verified in the damaged muscular tissue reinforces this possibility.
- ItemSomente MetadadadosQuantitative analysis of the hgh-affinity binding sites for [H-3]ouabain in the rat vas deferens and their immunological identification as the alpha(2) isoform of Na+/K+-ATPase(Elsevier B.V., 1998-05-01) Noel, François; Quintas, Luis Eduardo Menezes; Freitas, Eliana; Caricati-Neto, Afonso [UNIFESP]; Lafayette, Simone Sette Lopes [UNIFESP]; Wanderley, Almir Gonçalves [UNIFESP]; Jurkiewicz, Aron [UNIFESP]; Universidade Federal do Rio de Janeiro (UFRJ); Universidade Federal de São Paulo (UNIFESP)Binding assays were performed with [H-3]ouabain to investigate the presence of, and to characterize, a Na+/K+-ATPase isoform with high affinity for cardiac glycosides in the rat vas deferens. Nonlinear regression analysis of equilibrium experiments carried out with crude preparations in a Mg-P-i medium indicated the presence of high-affinity sites characterized with good precision (individual coefficients of variation = 11-35%) by their density (B-max = 0.42 to 0.72 pmol/mg protein) and dissociation constant (K-d = 0.069 to 0.136 mu M) values. the values of the dissociation rate constant (k(-1)) and the association rate constant (k(+1)) for these sites were 0.151 to 0.267 min(-1) and 2.87 to 3.60 mu M-1.min(-1), respectively. A higher number of low-affinity sites (K-d around 15 mu M), supposed to correspond to the alpha(1) isoform, was also identified, but their K-d and B-max values were not quantified precisely in this crude preparation. Western blot assays indicated hybridization with specific anti-alpha(1) and anti-alpha(2) isoform antibodies but not with anti-alpha(3) isoform antibody. Taken together, the present results indicate the existence of a low proportion of the alpha(2) isoform of Na+/K+-ATPase in the rat vas deferens that can be quantified precisely by [H-3]ouabain binding even in a crude membrane preparation that is suitable for studies under conditions of plasticity. (C) 1998 Elsevier Science Inc.
- ItemSomente MetadadadosRole of noradrenaline on the expression of the Na+/K+-ATPase alpha(2) isoform and the contractility of cultured rat vas deferens(Elsevier B.V., 2002-11-15) Quintas, Luis Eduardo Menezes; Lafayette, Simone Sette Lopes [UNIFESP]; Caricati-Neto, Afonso [UNIFESP]; Jurkiewicz, Aron [UNIFESP]; Noel, François; Universidade Federal do Rio de Janeiro (UFRJ); Universidade Federal de São Paulo (UNIFESP)Rat vasa deferentia were cultured for 3 days in Dulbecco's modified Eagle's medium in the absence or presence of 1 muM noradrenaline (NA) to investigate if the lack of NA release is the key factor to explain the selective reduction of the Na+/K+-ATPase alpha(2) isoform previously observed after in vivo denervation of this organ (Quintas et al., Biochem Pharmacol 2000;60:741-7). the lack of effects of the indirect sympathomimetic tyramine and the neuronal amine uptake blocker cocaine on NA curves indicated that cultured organs were denervated completely. Organ culture induced supersensitivity, expressed as a 6.3-fold increase of pD(2) and a 42% elevation of maximal contraction for NA but not for Ba2+. Western blotting indicated that the level of the alpha(1) isoform of Na+/K+-ATPase was unchanged after organ culture, but the alpha(2) isoform was down-regulated drastically to levels that were barely detectable. the addition of NA to the culture medium did not prevent the reduction of alpha(2) expression although it did impede NA supersensitivity (in fact a 4-fold decrease of pD(2) and a 32% reduction of maximal response were observed after incubation in the presence of NA). A striking reduction of L-type Ca2+ channel expression also was observed, indicated by an 85% decrease of [H-3]isradipine binding sites. These data suggest that NA is a trophic factor relevant to the control of muscle contraction, mediated by alpha(1)-adrenoceptors,but not to the expression of either Na+/K+-ATPase or the L-type Ca2+ channel. (C) 2002 Elsevier Science Inc. All rights reserved.
- ItemSomente MetadadadosTime-dependent up-regulation of Ca(2+) channels in vas deferens of newborn rats fed with breast milk of mothers under treatment with nifedipine(Elsevier B.V., 2008-12-03) Valera, Adriana Gonzalez [UNIFESP]; Verde, Luciana Ferreira [UNIFESP]; Lafayette, Simone Sette Lopes [UNIFESP]; Verreschi, Ieda Therezinha do Nascimento [UNIFESP]; Caricati-Neto, Afonso [UNIFESP]; Jurkiewicz, Aron [UNIFESP]; Jurkiewicz, Neide Hyppolito [UNIFESP]; Universidade Federal de São Paulo (UNIFESP); Universidade Federal de Pernambuco (UFPE)Our aim was to check for calcium channel maturation and regulation on newborn rats during breastfeeding by mothers treated with the L-type calcium channel blocker nifedipine. Contractions by KCl and radioligand binding techniques were used to verify if Call Channels are modified in rat vas deferens of 40-day old litters that were breastfed by mothers injected daily with nifedipine during nursery. Injections were applied in the beginning (1st until 8th day), middle (9th until 16th day), or end (17th until 24th day) of nursery, to verify the period of highest susceptibility of newborn to nifedipine receptor regulation. Contractile responses revealed that only after the middle period of treatment of mothers the maximal effects (E(max)) induced in pups by KCl were increased by about 35%, without changes of apparent affinity (pD(2)). Additionally, binding studies with [(3)H] Isradipine in cell membrane preparations showed a greater density (B(max)) of Ca(2+) channels by about 55%, without changes of affinity (K(d)). Changes were not detected after treatment of mothers in the beginning or end of breastfeeding. in addition, in vas deferens of 60-day old litters, the E(max) returned to control values, showing that changes were not persistent. Moreover, body and vas deferens weights and blood testosterone of newborn were never changed. the histology of mammary gland was similar for treated and control mothers, suggesting a stable milk production. It is concluded that nifedipine treatment of mothers, if made during the 9th to 16th day of lactation, produced a short lasting reversible up-regulation of L-type Ca(2+) channels. (C) 2008 Published by Elsevier B.V.