Godinho R O, Souccar C, Lapa A J
Department of Pharmacology, Escola Paulista de Medicina, São Paulo, Brazil.
Neurochem Res. 1994 Jun;19(6):657-63. doi: 10.1007/BF00967703.
The time course of effects of castration (5-60 days) and testosterone treatment (15-60 days) of adult male rats were examined on the endplate (+EP) and non-endplate (-EP) acetylcholinesterase (AChE) of the androgen-dependent levator ani (LA) muscle. The thiocholine method was used to determine the enzyme activity. Castration caused LA muscle atrophy within 5 days but reduced the -EP and +EP AChE after 10 and 20 days, respectively. Following 30 days castration -EP and +EP AChE reached respectively 41% and 35% of control activity. Testosterone retrieval restored the control values of both muscle weight and total AChE after 15 and 60 days, respectively. Recovery of the +EP AChE preceded that of -EP AChE by 30 days. The results showed that in the rat LA muscle, +EP and -EP AChE depend on a continuous testosterone regulation that predominates at +EP region spreading thereafter to -EP region. Those data suggest a hormone regulation of AChE exerted indirectly through the synthesis and release of neurotrophic substances.
