Incidence of hypertension is considered to be higher in type-2 diabetic subjects. However, in the mature obese Zucker rats, a genetic model for insulin resistant diabetes mellitus syndrome (NIDDM) blood pressures tend to be higher, but they are not consistently hypertensive. Objective of this study is to investigate whether obese Zucker rats are salt sensitive. Five week old obese and lean Zucker rats were placed on high salt diet (8% NaCl). After 7 to 8 weeks, mean blood pressures of salt-fed obese rats were significantly greater than that of obese rats on normal salt diet (153 vs 123 mmHg). High salt diet did not increase blood pressures in the lean rats. GFR, UV, UNaV were significantly higher in the salt fed obese rats under basal condition as well as during isotonic volume expansion (VE) with saline (3% body wt over 15 min). RBF and FENa were similar in both groups. In the lean rats, basal UV,UNaV and FENa were higher in the high salt group but RBF and GFR were not different. Both the lean groups responded to VE with similar increases in all the measured parameters. In both the obese and the lean rats on high salt diet, urinary potassium excretion (UKV) was lower during VE. Furthermore, high salt diet markedly enhanced blood levels of glucose and reduced plasma insulin and triglyceride levels in the obese rats. These studies suggest that despite their ability to handle salt and volume load, obese rats are highly sensitive to salt intake which could markedly aggravate NIDDM syndrome and contribute to hypertension.
|Original language||English (US)|
|State||Published - 1997|
ASJC Scopus subject areas
- Molecular Biology