Atenolol-induced regulation of leukocyte beta 2-adrenoceptors in hypertension.

beta 2-Adrenoceptor characteristics of human mononuclear leukocytes were assayed in hypertensive patients before and after treatment with 100 mg/day atenolol. While no changes have been observed in receptor affinity, a statistically significant increase (36%) has been demonstrated in receptor density following treatment. Blood pressure and heart rate were also measured in order to test the efficacy of the administered drug. All these parameters showed a fall in the post-treatment values. It is concluded that at therapeutic concentration, beta 2-adrenoceptors undergo up-regulation by atenolol in spite of its cardioselectivity. Such a regulation, which may represent a fundamental step in the mechanism leading to withdrawal syndrome, may, therefore, be suggested being quite widespread.