摘要:

SUMMARY To eraluate the role of altered efferent renal sympathetic nerve actirity in the exaggerated natriuresis of the spontaneous hypertensive rat (SHR), we measured efferent renal sympathetic nerve activity in anesthetized ageand sex-matched SHR and normotensive Wistar Kyoto (WKY) control rats during control and intravenous saline volume expansion. Mean arterial pressure was 40-60 mm Hg higher in SHR than in WKY. During volume expansion, the increment in urinary flow rate (17.5 ± 3.1 vs 42.8 ± 8.0 /J/100 g/min) and sodium excretion (8.1 ± 1.5 vs 15.2 ± 2 3MEq/min) were greater in SHR than in WKY. During control, efferent renal sympathetic nerve activity was 12.2 ± 0.4 Hz in WKY and 12.0 ± 0.5 Hz in SHR and fell equally during volume expansion to 5.0 ± 0.6 Hz in WKY and to 4.0 ± 0.8 Hz in SHR. Thus, these studies demonstrate that the exaggerated natriuresis of SHR as compared to WKY cannot be attributed to differences in reflex withdrawal of renal sympathetic nerve activity.

ISSN:0194-911X    

出版商:OVID    

年代:1981

数据来源: OVID

摘要:

SUMMARY To evaluate the mechanism of chronic thiazide diuretic action in hypertension, we treated 19 essential hypertensive white men for 1-month periods on placebo alone and hydrochlorothiazlde alone. During therapy, mean arterial pressure (MAP) fell, but radioisotopically determined intrarascular volume remained unchanged, suggesting other mechanisms of thiazide action upon blood pressure. In the renal circulation, thiazides did not change renal plasma flow or glomerular filtration rate, but renovascuiar resistance was diminished, probably at the afferent arteriole. Concomitant with the decline in blood pressure and renovascuiar resistance, urinary kallikrein excretion increased, from subnormal (hypertensive) levels back into the normal range. The kallikrein increase did not correlate with changes in plasma aldosterone. In addition, patients with blood pressure responses (reduction £ 10%) to thiazides (n = 12) had greater increases in kallikrein excretion than those without such a blood pressure decrement (n = 7), suggesting a role for renal kallikrein in the hypotensive response to thiazide diuretics.

ISSN:0194-911X    

出版商:OVID    

年代:1981

数据来源: OVID

ISSN:0194-911X    

出版商:OVID    

年代:1981

数据来源: OVID