Temperature sensitivity of cardiac muscarinic receptors in bat atria and ventricle.
In contrast to other mammals, muscarinic receptors in the bat ventricle can mediate significant decrease in basal contractile force (greater than 50%), not only at 37 degrees C but also at hibernation temperature (12 degrees C). At frequencies of contraction that approximate in vivo values for 37-12 degrees C, no significant shift in receptor affinity or maximum response to applied acetylcholine was found for either ventricular or atrial muscle. Low temperature does not appear to compromise receptor function in hibernators. The atypical cholinergic innervation of the ventricle may maintain a regulative role during hibernation.
D000109:Acetylcholine / Q000494:pharmacology; D000818:Animals; D016275:Atrial Function; D002685:Chiroptera / Q000502:physiology*; D066298:In Vitro Techniques; D009200:Myocardial Contraction / Q000187:drug effects; D011976:Receptors, Muscarinic / Q000502:physiology*; D013696:Temperature; D016276:Ventricular Function
D011976:Receptors, Muscarinic; D000109:Acetylcholine