Effects of chronic arachidonate on blood pressure of spontaneously hypertensive rats.
Three weeks of treatment with arachidonic acid (250 mg/kg/day, s.c.) produced an antihypertensive effect in 16 week-old spontaneously hypertensive rats (SHR) as compared with vehicle treated rats. Indomethacin (4 mg/kg, s.c. B.I.D.), given concurrently with arachidonate, abolished the antihypertensive effect. Plasma catecholamines were not altered by the arachidonate treatment, but blood pressure increments after spinal cord stimulation or after intravenous administration of norepinephrine and angiotensin II in the pithed rat were diminished. Increments in plasma catecholamines in response to spinal cord stimulation were similar in both groups of pithed rats. These data demonstrate the antihypertensive effect of arachidonic acid in SHR with established hypertension. This beneficial effect seems to be mediated through cyclooxygenase metabolites, and might be related to reduced responsiveness of peripheral blood vessels to pressor stimuli.
D000804:Angiotensin II / Q000494:pharmacology; D000818:Animals; D016718:Arachidonic Acid; D001095:Arachidonic Acids / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D001794:Blood Pressure / Q000187:drug effects*; D001835:Body Weight / Q000187:drug effects; D002395:Catecholamines / Q000097:blood; D006973:Hypertension / Q000188:drug therapy*; D007213:Indomethacin / Q000494:pharmacology; D008297:Male; D009638:Norepinephrine / Q000494:pharmacology; D011311:Pressoreceptors / Q000187:drug effects; D051381:Rats; D011919:Rats, Inbred Strains; D013564:Sympathetic Nervous System / Q000502:physiology; D013997:Time Factors; D014655:Vascular Resistance / Q000187:drug effects
D001095:Arachidonic Acids; D002395:Catecholamines; D000804:Angiotensin II; D016718:Arachidonic Acid; D009638:Norepinephrine; D007213:Indomethacin