Study 2 built on prior research on gender differences in total peripheral resistance during stressors which enhance alpha-adrenergic activity, and on a recent observation that among young adults, slow sodium excretion during stress is seen in five times as many men as women. It also built on recent work suggesting that estrogen may attenuate total peripheral resistance responses to stress by reducing vasoconstrictive effects of alpha-adrenergic activity. The study was designed to examine cardiovascular, lipid, epinephrine, norepinephrine, and sodium excretion responses to stressors in 120 subjects maintained for a week on a controlled high salt diet. Thirty subjects were tested in each of these groups: 1) premenopausal women, 2) postmenopausal women not using hormone replacement therapy, 3) postmenopausal women using hormone replacement, 4) men. Each group included 15 Black and 15 white subjects, and each subject was tested twice, once after receiving placebo and once after receiving either an alpha- or a beta-receptor antagonist.