Effects of mental and physical stress on plasma catecholamine levels before and after beta-adrenoceptor blocker treatment.

In a study in mild hypertensives, the impact of mental and physical stress on plasma epinephrine (E), norepinephrine (NE), and on their ratio (NE/E) was evaluated. The effect of two beta-adrenoceptor blocking drugs, atenolol and bopindolol, on plasma catecholamine levels was also examined. Each stressful stimulus significantly increased the NE and E levels compared to rest. The increase was progressive from mental stress, through the handgrip test to the treadmill test. A slight decrease in the NE/E ratio was observed following mental stress and the handgrip test, while this ratio increased during the treadmill test. No significant impact of beta blocking treatment on catecholamine levels was observed under any test condition.