Autonomic receptor interactions in isolated cardiac myocytes from hypertensive rats

摘要: Abstract Isolated ventricular myocytes from adult (16 to 20 weeks) spontaneously hypertensive (SHR) and normotensive (WKY) rats were utilized examine adrenergic cholinergic receptor expression interaction. Binding assays performed using quinuclidinyl benzilate (QNB) iodocyanopindolol (ICYP) for β-adrenergic receptors, respectively. In addition, cAMP was measured as an index of adrenergic-cholinergic control adenylate cyclase. Data radioligand binding experiments indicated that muscarinic receptors depressed (22%) in SHR myocytes, while density comparable WKY myocytes. Heterologous modulation isolated assessed by displacement analysis with without guanosine 5′-triphosphate (GTP), showed carbachol QNB shifted five fold the right presence GTP agonist isoproterenol did not prevent GTP-mediated alteration. contrast, modulated GTP-shift ICYP these effects both Furthermore, ability blunt stimulation cyclase also animals. Thus, observed decrement alter interactions guanine nucleotides, or levels. provide a useful system analyzing regulation how parameters may be altered heart.