Partial mediation by nitric oxide of the relaxation of human isolated detrusor strips in response to electrical field stimulation.
1. A method for reproducing relaxation of human isolated detrusor smooth muscle in vitro in response to electrical field stimulation is described. 2. The parameters of stimulation associated with relaxation were those which would be expected to give a largely nerve-mediated response: the relaxations were not reduced by tetrodotoxin (3 x 10(-7) M) and were therefore not dependent on voltage sensitive sodium channels. 3. The relaxations were decreased (mean 74.1%) by nitro L-arginine (NOARG, 10(-5) M). 4. Methylene blue (10(-5) M), an inhibitor of soluble guanylate cyclase, abolished the relaxations. 5. These results indicate that there may be a relaxation mechanism in the human bladder which is at least partly mediated via the production of nitric oxide.
James
M J
MJ
Department of Physiology and Pharmacology, University of Nottingham Medical School, Queen's Medical Centre.
Birmingham
A T
AT
Hill
S J
SJ
D001120:Arginine / Q000031:analogs & derivatives / Q000494:pharmacology; D004558:Electric Stimulation; D006801:Humans; D066298:In Vitro Techniques; D007213:Indomethacin / Q000494:pharmacology; D008751:Methylene Blue / Q000494:pharmacology; D009119:Muscle Contraction / Q000187:drug effects / Q000502:physiology; D009126:Muscle Relaxation / Q000187:drug effects*; D009130:Muscle, Smooth / Q000187:drug effects* / Q000294:innervation; D009569:Nitric Oxide / Q000494:pharmacology*; D019335:Nitroarginine; D011433:Propranolol / Q000494:pharmacology; D013779:Tetrodotoxin / Q000494:pharmacology
D019335:Nitroarginine; D009569:Nitric Oxide; D013779:Tetrodotoxin; D001120:Arginine; D011433:Propranolol; D008751:Methylene Blue; D007213:Indomethacin