RT Journal Article
SR Electronic
T1 Effects of nitric oxide-related agents on rat testicular function.
JF Journal of Pharmacology and Experimental Therapeutics
JO J Pharmacol Exp Ther
FD American Society for Pharmacology and Experimental Therapeutics
SP 230
OP 237
VO 269
IS 1
A1 M L Adams
A1 E R Meyer
A1 B N Sewing
A1 T J Cicero
YR 1994
UL http://jpet.aspetjournals.org/content/269/1/230.abstract
AB The effects of nitric oxide (NO)-related agents on testicular function were examined in male rats with measurements of serum luteinizing hormone, serum testosterone, testicular interstitial fluid (TIF) testosterone, and TIF volumes. Serum and TIF testosterone levels and luteinizing hormone secretion were significantly decreased by the NO donor, isosorbide dinitrate (ISDN), and the NO synthase (NOS) substrate, L-arginine methyl ester, a source for the endogenous production of NO. The effects of ISDN on TIF volumes were inconsistent, but L-arginine methyl ester decreased TIF formation in a dose-dependent manner. In addition, ISDN dose dependently suppressed testosterone secretion stimulated by human chorionic gonadotropin treatment, suggesting that the effects on testosterone secretion were independent of changes in secretion of the endogenous gonadotropin luteinizing hormone. ISDN, L-arginine methyl ester, and the endogenous NOS substrate L-arginine completely blocked testosterone secretion stimulated by the NOS inhibitor NG-nitro-L-arginine methyl ester (NAME), whereas the relatively inactive NOS substrate, D-arginine, only partially blocked NAME-stimulated testosterone secretion. Hydralazine and nicardipine, two vasodilators that do not exhibit prominent NO-related effects, also blocked basal testosterone secretion and testosterone secretion stimulated by the vasoconstrictor NAME.(ABSTRACT TRUNCATED AT 250 WORDS)