title: Relaxing effects induced by the soluble guanylyl cyclase stimulator BAY 41-2272 in human and rabbit corpus cavernosum.
abstract: 5-Cyclopropyl-2-[1-(2-fluoro-benzyl)-1H-pyrazolo[3,4-b]pyridin-3-yl]-pyrimidin-4-ylamine (BAY 41-2272) is a potent soluble guanylyl cyclase stimulator in a nitric oxide (NO)-independent manner. The relaxant effect of BAY 41-2272 was investigated in rabbit and human corpus cavernosum in vitro. BAY 41-2272 (0.01-10 microM) relaxed both rabbit (pEC(50)=6.82+/-0.06) and human (pEC(50)=6.12+/-0.10) precontracted cavernosal strips. The guanylyl cyclase inhibitor (ODQ, 10 microM) caused significant rightward shifts in the concentration-response curves for BAY 41-2272 in rabbit (4.7-fold) and human (2.3-fold) tissues. The NO synthesis inhibitor (N-nitro-L-arginine methyl ester (L-NAME), 100 microM) also produced similar rightward shifts, revealing that BAY 41-2272 acts synergistically with endogenous NO to elicit its relaxant effect. The results also indicate that ODQ is selective for the NO-stimulated enzyme, since relaxations evoked by BAY 41-2272 were only partly attenuated by ODQ. The present study shows that both BAY 41-2272 and sildenafil evoke relaxations independent of inhibition of haem in soluble guanylate cyclase. Moreover, there is no synergistic effect of the two compounds in corpus cavernosum.
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000818:Animals; D000242:Cyclic AMP / Q000378:metabolism; D004357:Drug Synergism; D020536:Enzyme Activators / Q000494:pharmacology*; D006162:Guanylate Cyclase / Q000037:antagonists & inhibitors / Q000378:metabolism*; D006801:Humans; D066298:In Vitro Techniques; D007537:Isometric Contraction / Q000187:drug effects; D008297:Male; D008875:Middle Aged; D009126:Muscle Relaxation / Q000187:drug effects; D019331:NG-Nitroarginine Methyl Ester / Q000494:pharmacology; D009569:Nitric Oxide / Q000378:metabolism; D019001:Nitric Oxide Synthase / Q000037:antagonists & inhibitors; D010069:Oxadiazoles / Q000494:pharmacology; D010413:Penis / Q000187:drug effects* / Q000502:physiology; D011720:Pyrazoles / Q000494:pharmacology*; D011725:Pyridines / Q000494:pharmacology*; D011817:Rabbits
chemical_list: C116907:1H-(1,2,4)oxadiazolo(4,3-a)-quiloxalin-1-one; C423582:3-(4-Amino-5-cyclopropylpyrimidine-2-yl)-1-(2-fluorobenzyl)-1H-pyrazolo(3,4-b)pyridine; D020536:Enzyme Activators; D010069:Oxadiazoles; D011720:Pyrazoles; D011725:Pyridines; D009569:Nitric Oxide; D000242:Cyclic AMP; D019001:Nitric Oxide Synthase; D006162:Guanylate Cyclase; D019331:NG-Nitroarginine Methyl Ester