title: Alpha-adrenoceptors, adrenaline, and exaggerated vasoconstrictor response to stress in essential hypertension.
abstract: Stressful sympathetic stimulation by cold pressor test in patients with essential hypertension results in an exaggerated response of the already elevated plasma adrenaline, heart rate, blood pressure, and alpha-adrenoceptor-mediated vasoconstriction when compared with normotensive subjects. The stress-induced increase in adrenaline was correlated with the attendant increase in blood pressure. The stress-induced reduction in forearm flow was reversed during infusion of the postjunctional alpha 1-adrenoceptor blocker prazosin. Therefore, enhanced responses to sympathetic stress, as reflected and perhaps caused by an exaggerated rise in plasma adrenaline, may contribute to an increased alpha 1-adrenoceptor-mediated vasoconstriction in essential hypertension.
mesh_terms: D000328:Adult; D001794:Blood Pressure; D003080:Cold Temperature; D004837:Epinephrine / Q000097:blood*; D006339:Heart Rate; D006801:Humans; D006973:Hypertension / Q000175:diagnosis / Q000503:physiopathology*; D008875:Middle Aged; D011224:Prazosin / Q000494:pharmacology; D011941:Receptors, Adrenergic / Q000502:physiology*; D011942:Receptors, Adrenergic, alpha / Q000187:drug effects / Q000502:physiology*; D013312:Stress, Physiological / Q000503:physiopathology; D014661:Vasoconstriction; D014666:Vasomotor System / Q000187:drug effects
chemical_list: D011941:Receptors, Adrenergic; D011942:Receptors, Adrenergic, alpha; D011224:Prazosin; D004837:Epinephrine