title: Mechanism of the hypotensive action of practolol in the anesthetized rat.
abstract: Cardiovascular effects of acute administration of practolol were studied in groups of normotensive and spontaneously hypertensive rats. In some of these animals a strong and long-lasting hypotension was shown, resulting from a decrease in the total peripheral resistance. This hypotension was impaired by preventive propranolol administration, and did not result from a direct vascular effect. Moreover, it was previously reported that practolol induced a strong and long-lasting hypotension in all normotensive and hypertensive rats after blood-brain barrier disruption. From these experiments it is suggested that the blood pressure decrease observed in some groups of Okamoto rats may be due to a practolol action on central beta-receptors. The intensity of hypotension depends on the molecule penetration in the central nervous system, and seems to be related to blood-brain barrier lesions induced by genetic hypertension.
mesh_terms: D000818:Animals; D000959:Antihypertensive Agents; D001794:Blood Pressure / Q000187:drug effects*; D006973:Hypertension / Q000188:drug therapy; D008297:Male; D011217:Practolol / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains; D014655:Vascular Resistance / Q000187:drug effects; D014664:Vasodilation / Q000187:drug effects
chemical_list: D000959:Antihypertensive Agents; D011217:Practolol