Propranolol stimulates testicular interstitial fluid formation and testosterone secretion in rats.
We investigated the effect of intratesticularly injected propranolol on testicular interstitial fluid (TIF) formation and on testosterone levels in the TIF of intact adult male Wistar rats (4-9 rats per group). dl-propranolol at doses of 0.6, 1.2, or 6.0 mg/kg was injected into the left (L) testis whereas the right (R) testis (control testis) received vehicle. dl-propranolol (6.0 mg/kg) caused a significant increase in both TIF volume (329%) and TIF levels of testosterone (257%) in the L testis but not in the R (control) testis 3 h post-injection. In rats treated simultaneously with human chorionic gonadotropin (hCG, 5 IU/rat, sc) the same dose or propranolol (6.0 mg/kg) significantly increased the stimulatory effect of hCG on testosterone secretion by 1.8-fold, but hCG did not modify the stimulatory effect of propranolol on TIF volume. These results demonstrate a direct stimulatory effect of propranolol on TIF volume and testosterone secretion, both under basal and hCG-stimulated conditions.
Martins
M C
MC
Departamento de Fisiologia, Universidade Federal do Piauí Teresina, Brasil.
Udrisar
D P
DP
Wanderley
M I
MI
D000818:Animals; D006063:Chorionic Gonadotropin / Q000494:pharmacology; D005110:Extracellular Space / Q000187:drug effects; D007985:Leydig Cells / Q000187:drug effects*; D008297:Male; D011433:Propranolol / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D013739:Testosterone / Q000378:metabolism*
D006063:Chorionic Gonadotropin; D013739:Testosterone; D011433:Propranolol