The affinity of some selective muscarinic receptor antagonists for the muscarinic receptor mediating endothelial-dependent relaxation of the rabbit and rat thoracic aorta.
The pKB values determined for pirenzepine, 4-DAMP, secoverine and gallamine against acetylcholine-mediated relaxant effects in rabbit aorta indicate that this muscarinic receptor closely resembles that which mediates contraction of non-vascular smooth muscle. The results of the present study argue against the presence of a novel type of muscarinic receptor mediating endothelium-dependent relaxation.
D000109:Acetylcholine / Q000494:pharmacology; D000818:Animals; D001013:Aorta, Thoracic / Q000187:drug effects; D004727:Endothelium / Q000502:physiology; D066298:In Vitro Techniques; D009126:Muscle Relaxation / Q000187:drug effects; D009131:Muscle, Smooth, Vascular / Q000187:drug effects*; D010276:Parasympatholytics / Q000378:metabolism*; D011817:Rabbits; D051381:Rats; D011976:Receptors, Muscarinic / Q000378:metabolism*; D013045:Species Specificity
D010276:Parasympatholytics; D011976:Receptors, Muscarinic; D000109:Acetylcholine