DECREASED CONCENTRATION OF MYOCARDIAL α‐ADRENOCEPTORS WITH INCREASING AGE IN FOETAL LAMBS

Abstract

Using [3H]‐dihydroergocryptine, we identified myocardial α‐adrenoceptor binding sites in foetal lambs and demonstrated that the concentration of receptors decreased with increasing foetal age. The presence of the receptor in the foetus correlated with the presence of myocardial α‐adrenergic responsiveness. However, we found neither the α‐receptor binding site nor responsiveness to α‐adrenoceptor stimulation in the myocardium of adult sheep. 1980 British Pharmacological Society