NADPH-diaphorase and NANC relaxations are correlated in the sheep urinary tract.
The present investigation was performed with the purpose of revealing by histochemical examination of NADPH-diaphorase activity and electrical field stimulation (EFS) of isolated preparations in vitro, whether a nitrergic innervation is present in the lower urinary tract of the sheep. NADPH-diaphorase positive fibers were found in the trigone and urethra, but not in detrusor and ureter. EFS elicited L-nitroarginine-sensitive relaxations of precontracted preparations from the trigone and urethra while it did not relax detrusor and ureteral preparations. The present results show a direct regional correlation between the NADPH-diaphorase activity and EFS-induced relaxations, and suggest the presence of an inhibitory nitrergic innervation, which might be of importance for relaxation of the bladder neck and urethra during voiding.
Triguero
D
D
Department of Physiology, Veterinary School, Complutense University, Ciudad Universitaria, Madrid, Spain.
Prieto
D
D
García-Pascual
A
A
D000818:Animals; D001120:Arginine / Q000031:analogs & derivatives / Q000494:pharmacology; D001341:Autonomic Nervous System / Q000502:physiology*; D004558:Electric Stimulation; D005260:Female; D006651:Histocytochemistry; D066298:In Vitro Techniques; D009126:Muscle Relaxation / Q000502:physiology; D009130:Muscle, Smooth / Q000201:enzymology / Q000294:innervation / Q000502:physiology*; D009252:NADPH Dehydrogenase / Q000378:metabolism*; D019335:Nitroarginine; D012756:Sheep; D014551:Urinary Tract / Q000201:enzymology / Q000294:innervation; D014553:Urinary Tract Physiological Phenomena
D019335:Nitroarginine; D001120:Arginine; D009252:NADPH Dehydrogenase