EFFLUX OF ACETYLCHOLINE IN DIMORPHIC SKELETAL-MUSCLE FROM CASTRATED MALE-RATS

EFFLUX OF ACETYLCHOLINE IN DIMORPHIC SKELETAL-MUSCLE FROM CASTRATED MALE-RATS

Author Lima-Landman, Maria Teresa Riggio de Autor UNIFESP Google Scholar
Goncalo, M. C. Google Scholar
Lapa, Antonio José Autor UNIFESP Google Scholar
Institution Universidade Federal de São Paulo (UNIFESP)
Abstract The effect of testosterone on motor neurons of dimorphic muscles is demonstrable by the increased frequency of miniature end-plate potentials (mepp) and decreased end-plate acetylcholinesterase activity observed in castrated rats. No change occurs in induced acetylcholine (ACh) release. Although these muscles atrophy after castration there is no loss of muscle fibers. In the present study we reinvestigate the neuromuscular transmission in levator ani (LA) muscles from normal (N) adult (120 days) male rats and from rats castrated (C) 30 days before. The measurement of radioactive [H-3]-choline was used to evaluate ACh release since it permits simultaneous estimation of quantal and non-quantal ACh release. The LA muscle was incubated with [H-3]-choline (1-mu-Ci/ml) for 30 min and ACh efflux was measured after washout. The basal release of [H-3]-choline (dpm total tissue radioactivity-1 number of fibers-1) was 296 +/- 33 and 156 +/- 24 in N and C, respectively. Induced ACh release (25 Hz, 5 min) was the same in N and C (653.19 +/- 66.46 and 496.62 +/- 68.67, respectively). These results indicate that castration increased mepp frequency but reduced the total spontaneous release of ACh.
Keywords LEVATOR ANI MUSCLE
ACETYLCHOLINE EFFLUX
TESTOSTERONE
CASTRATION
MEPP FREQUENCY
Language English
Date 1991-01-01
Published in Brazilian Journal Of Medical And Biological Research. Sao Paulo: Assoc Bras Divulg Cientifica, v. 24, n. 11, p. 1137-1140, 1991.
ISSN 0100-879X (Sherpa/Romeo, impact factor)
Publisher Assoc Bras Divulg Cientifica
Extent 1137-1140
Access rights Closed access
Type Article
Web of Science ID WOS:A1991GW65200010
URI http://repositorio.unifesp.br/11600/43001

Show full item record




File

File Size Format View

There are no files associated with this item.

This item appears in the following Collection(s)

Search


Browse

Statistics

My Account