[Effect of electrical stimulation of the area postrema on plasma renin activity and renal sympathetic nerve activity in rabbits].
68 urethan-anesthetized rabbits were prepared for registration of changes of respiration, arterial blood pressure (BP), heart rate (HR) and renal sympathetic nerve activity (RSNA) due to stimulation of area postrema (AP) by rectangular pulse trains each lasting for 4 s for every 30 s. During 40 min of such a stimulation paradigm the venous blood samples were collected for radioimmunoassay of plasma renin activity (PRA) (both pre- and post-stimulation), RSNA registered and processed by a computer. Animals were divided into three groups: (1) with AP stimulation only (n = 47); (2) AP stimulation after bilateral renal denervation (n = 13); (3) AP stimulation after propranolol injection (n = 8). In Group I, a 91% increase in PRA, an augmentation of RSNA, a rise of BP and a decrease of HR were observed, while respiration did not show obvious change. In Group II, hemodynamic and RSNA response was similar to that in Group I, but PRA was not changed significantly. In Group III, the effects on BP, HR, respiration and RSNA showed no remarkable changes compared with Group I, but significant inhibition of the response of PRA [from 0.65 +/- 0.07 ng/(ml.h-1) to 0.72 +/- 0.10 ng/(ml.h-1), P > 0.05] was observed. The results mentioned above suggested that electrical stimulation of AP may induce an increase in renin release and renal sympathetic nerve activity and hemodynamic changes in rabbits.
Qui
H
H
Department of Physiology, Shandong Medical Academy, Jinan.
Chai
X S
XS
D000818:Animals; D001794:Blood Pressure; D004558:Electric Stimulation; D005260:Female; D006339:Heart Rate; D007668:Kidney / Q000294:innervation*; D008297:Male; D008526:Medulla Oblongata / Q000502:physiology*; D011433:Propranolol / Q000494:pharmacology; D011817:Rabbits; D012083:Renin / Q000097:blood*; D012119:Respiration / Q000502:physiology; D013564:Sympathetic Nervous System / Q000502:physiology*
D011433:Propranolol; D012083:Renin