A comparison of cardiac alpha-adrenoceptor number and affinity between aorta-coarcted hypertensive and normotensive rats.
Aorta-coarcted hypertensive rats (AHR) and sham-operated normotensive rats (SNR) were compared in order to assess the effect of elevated blood pressure (BP) on the concentration and affinity of cardiac adrenoceptors in these rats at different stages of hypertension. Body weight was significantly reduced, mean arterial blood pressure (MABP) and the ratio by ventricle/body weight (index of hypertropy) were significantly increased in coarcted rats at 2, 6 and 28 days after ligation of the abdominal aorta. Myocardial membranes prepared from hypertensive rats at various stages of hypertension contained the same concentration of cardiac alpha-adrenoceptors as compared to corresponding time-matched, sham-operated controls. In addition, the receptor affinity for the radioligand was similar between hypertensive rats and their respective controls. Thus, aorta-coarctation induced hypertension is not associated with any alterations in cardiac alpha-adrenoceptors, which is different from reports in other models of experimental hypertension.
D000818:Animals; D001012:Aorta, Abdominal / Q000502:physiology*; D006332:Cardiomegaly / Q000209:etiology; D006973:Hypertension / Q000209:etiology / Q000378:metabolism*; D008026:Ligation; D008297:Male; D009206:Myocardium / Q000032:analysis*; D051381:Rats; D011919:Rats, Inbred Strains; D011942:Receptors, Adrenergic, alpha / Q000032:analysis / Q000378:metabolism*
D011942:Receptors, Adrenergic, alpha