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The effects of the menstrual cycle, race, and gender on adrenergic receptors and agonists*

1996; Wiley; Volume: 60; Issue: 1 Linguagem: Inglês

10.1016/s0009-9236(96)90172-1

1532-6535

Paul J. Mills, Michael G. Ziegler, Richard A. Nelesen, Brian P. Kennedy,

Neuropeptides and Animal Physiology

Objective To examine possible effects of race, sex, and the menstrual cycle on adrenergic receptors (β2 and α2) and agonists. Methods Sixty-three normotensive black men and women and white men and women were studied twice, approximately 6 weeks apart. Women were studied once during the follicular phase and once during the luteal phase of the menstrual cycle. β2-Adrenergic receptors and adenylate cyclase activity were examined on lymphocytes, and α2-adrenergic receptors were examined on platelets. Norepinephrine and epinephrine were determined in plasma. Results Women showed greater lymphocyte β2-receptor sensitivity (isoproterenol-stimulated cyclic adenosine monophosphate; p = 0.009). Women also showed greater postreceptor adenylate cycle activity independent of the β-receptor (forskolin stimulation; p = 0.006). When these differences were controlled for, the gender-related differences in β2-receptor sensitivity were no longer evident. Black women had a reduced β2-receptor sensitivity in the luteal phase compared with the follicular phase, whereas white women showed no significant change (p = 0.018). Black subjects had lower lymphocyte β2-receptor density (Bmax) values than white subjects (p = 0.047). There were no significant effects on α2-adrenergic receptors. Conclusion The findings suggest that although there is no generalized effect of the menstrual cycle on adrenergic receptors in white women, such an effect may occur in black women. The findings also suggest that previously reported gender-related differences in β2-receptor sensitivity may be due to gender-related differences in postreceptor activity and not the β2-receptor per se. Clinical Pharmacology & Therapeutics (1996) 60, 99–104; doi: