title: The antihypertensive effects of a pure and selective serotonin-receptor blocking agent (R 41 468) in elderly patients.
abstract: In a first experiment, an acute intravenous administration of 10 mg R 41 468, a pure serotonin-receptor blocking agent with high selectivity for blood vessels and thrombocytes and devoid of central effects, dramatically reduced systolic and diastolic blood pressure in 23 elderly hypertensive patients. Heart rate and cardiac output remained virtually unchanged. In a second double-blind placebo-controlled cross-over study a highly significant decrease of systolic and diastolic blood pressure was obtained in 14 elderly hypertensive patients during an 8-day oral treatment with 40 mg t.i.d. of R 41 468. No serious side-effects were observed. An oral maintenance therapy with R 41 468 for 3 weeks showed a further reduction of blood pressure, resulting in a normalization of blood pressure, taking into account the advanced age of the patients. R 41 468 most probably acts by decreasing the venous capacitance bed constriction. Essential hypertension might be causally related to an impairment of venous function, in which serotonin might be an important pressor factor.
mesh_terms: D000367:Age Factors; D000368:Aged; D000959:Antihypertensive Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D001794:Blood Pressure / Q000187:drug effects*; D002986:Clinical Trials as Topic; D003864:Depression, Chemical; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D006973:Hypertension / Q000188:drug therapy*; D007275:Injections, Intravenous; D007650:Ketanserin; D008297:Male; D008875:Middle Aged; D009200:Myocardial Contraction / Q000187:drug effects; D010880:Piperidines / Q000008:administration & dosage / Q000627:therapeutic use*; D010919:Placebos; D011985:Receptors, Serotonin / Q000187:drug effects*; D012107:Research Design; D012702:Serotonin Antagonists / Q000627:therapeutic use*
chemical_list: D000959:Antihypertensive Agents; D010880:Piperidines; D010919:Placebos; D011985:Receptors, Serotonin; D012702:Serotonin Antagonists; D007650:Ketanserin