Rapid hypotensive response to fasting in spontaneously hypertensive rats.
This study examined changes in renal function and mean arterial pressure (MAP) in spontaneously hypertensive (SHR) and Wistar-Kyoto (WKY) rats during 48 h of fasting, independent of changes in sodium intake. Spontaneously hypertensive rats (n = 17) and WKY rats (n = 10) were instrumented with artery and vein catheters and sodium intake was clamped at 2.1 mEq/day. By day 2 of fasting, MAP decreased -10+/-1 mm Hg (P < .001) in SHR, but did not change significantly in WKY rats. Heart rate decreased significantly in both groups by day 2 of fasting and there was a significant increase in urine volume and sodium excretion. Thus, fasting caused a rapid decrease in MAP in SHR that was not due to decreased sodium intake, but may be related, in part, to volume loss and improved renal excretory function.
Fitzgerald
S M
SM
Department of Physiology and Biophysics, University of Mississippi Medical Center, Jackson, USA. sharyn.fitzgerald@fysiologi.gu.se
Hall
J E
JE
Brands
M W
MW
D000818:Animals; D001794:Blood Pressure; D005215:Fasting; D006339:Heart Rate; D006973:Hypertension / Q000178:diet therapy* / Q000503:physiopathology; D008297:Male; D009318:Natriuresis; D051381:Rats; D011918:Rats, Inbred SHR; D011921:Rats, Inbred WKY; D017673:Sodium Chloride, Dietary / Q000009:adverse effects; D013564:Sympathetic Nervous System / Q000503:physiopathology; D013997:Time Factors; D016896:Treatment Outcome; D015431:Weight Loss
D017673:Sodium Chloride, Dietary