title: Circulatory dose-response effects of hydrochlorothiazide at rest and during dynamic exercise in essential hypertension.
abstract: The immediate and sustained circulatory effects of hydrochlorothiazide were evaluated at rest and during dynamic exercise in 24 patients with essential hypertension. Twenty-four hours after the first dose (50mg) there was a reduction in the resting systolic blood pressure, with attenuation of exercise tachycardia. During sustained therapy at two dose levels (50mg and 100mg), each of one month's duration, the systolic and diastolic blood pressure were reduced, both at rest and during dynamic exercise, without substantial difference between the two doses. Exercise tachycardia was attenuated during longterm treatment, without alteration of the pressor responses to exercise. The reduction in exercise tachycardia at the same workload in this study suggests that thiazides, in addition to their diuretic action, have a vascular component that augments the fall in systemic vascular resistance during dynamic exercise.
mesh_terms: D000328:Adult; D001794:Blood Pressure / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D006339:Heart Rate / Q000187:drug effects; D006439:Hemodynamics / Q000187:drug effects*; D006801:Humans; D006852:Hydrochlorothiazide / Q000494:pharmacology*; D006973:Hypertension / Q000188:drug therapy* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D005082:Physical Exertion; D012146:Rest
chemical_list: D006852:Hydrochlorothiazide