Elevation of blood pressure in hypertensive rats after lesioning serotonin nerves in the dorsomedial medulla oblongata.
The possibility that serotonin (5HT) nerve endings in the dorsomedial medulla oblongata participate in the control of blood pressure was investigated in stroke-prone hypertensive rats and in normotensive rats. 5HT nerves were destroyed by injecting 5,7-dihydroxytryptamine bilaterally into the solitary tract nucleus. Immunohistochemical and biochemical examination revealed a selective loss of 5HT nerves throughout the dorsomedial medulla with little damage in adjacent regions. Arterial blood pressure and heart rate, measured at daily intervals, were similar in lesioned and sham-operated normotensive rats. However, in the hypertensive rats, blood pressure was substantially elevated at 6-9 days after the lesions compared with sham operations. There were no accompanying changes in heart rate.
D000818:Animals; D001794:Blood Pressure; D006973:Hypertension / Q000503:physiopathology*; D008297:Male; D008526:Medulla Oblongata / Q000502:physiology*; D009411:Nerve Endings / Q000502:physiology*; D051381:Rats; D011919:Rats, Inbred Strains; D012701:Serotonin / Q000502:physiology*
D012701:Serotonin