BACKGROUND: In previous studies we reported an altered prostanoid (PR) release-pattern in mesenteric vessels in fructose (F)-overloaded rats, an experimental model of insulin resistance and hypertension. Dehydroepiandrosterone (DHEA) and its precursor Dehydroepiandrosterone sulfate (DHEA-S) are the most abundant circulating steroid hormones produced by the adrenal and recent studies in both cells and animals suggest that DHEA may have acute non-genomic actions that mimic both metabolic and vascular actions of insulin. AIM OF THE STUDY: This study was to analyze in F-overloaded rats, the effects of DHEA treatment on arterial blood pressure and the PR production in mesenteric vessels and aorta. METHODS: Male 6 week-old Sprague-Dawley rats were randomly divided in four groups: a control group (C), a DHEA (30 mg/kg/sc/48 h)-treated group (D), a fructose (10% w/v in drinking water)-fed group (F), and both treatments simultaneously group (FD). The systolic blood pressure (SBP) was measured by tail cuff method and glycemia and triglyderidemia were measured by enzymatic assays. The mesenteric beds of all groups were dissected, and incubated in Krebs solution. The PR released were measured by HPLC. RESULTS: F overload increased SBP and triglyceridemia and decreased the mesenteric vasodilatory PR release. DHEA treatment prevented the increment in SBP and triglyceridemia and decreased vasoconstrictor PR in F-treated rats. CONCLUSION: DHEA normalize the PGI(2)/TX ratio, diminished in F-overloaded rats, through the decrease in thromboxane (TX) production and this could be one of the mechanisms by which DHEA prevented the slight hypertension in F-animals.
BACKGROUND: In previous studies we reported an altered prostanoid (PR) release-pattern in mesenteric vessels in fructose (F)-overloaded rats, an experimental model of insulin resistance and hypertension. Dehydroepiandrosterone (DHEA) and its precursor Dehydroepiandrosterone sulfate (DHEA-S) are the most abundant circulating steroid hormones produced by the adrenal and recent studies in both cells and animals suggest that DHEA may have acute non-genomic actions that mimic both metabolic and vascular actions of insulin. AIM OF THE STUDY: This study was to analyze in F-overloaded rats, the effects of DHEA treatment on arterial blood pressure and the PR production in mesenteric vessels and aorta. METHODS: Male 6 week-old Sprague-Dawley rats were randomly divided in four groups: a control group (C), a DHEA (30 mg/kg/sc/48 h)-treated group (D), a fructose (10% w/v in drinking water)-fed group (F), and both treatments simultaneously group (FD). The systolic blood pressure (SBP) was measured by tail cuff method and glycemia and triglyderidemia were measured by enzymatic assays. The mesenteric beds of all groups were dissected, and incubated in Krebs solution. The PR released were measured by HPLC. RESULTS: F overload increased SBP and triglyceridemia and decreased the mesenteric vasodilatory PR release. DHEA treatment prevented the increment in SBP and triglyceridemia and decreased vasoconstrictor PR in F-treated rats. CONCLUSION:DHEA normalize the PGI(2)/TX ratio, diminished in F-overloaded rats, through the decrease in thromboxane (TX) production and this could be one of the mechanisms by which DHEA prevented the slight hypertension in F-animals.
Authors: R T Holman; S B Johnson; J M Gerrard; S M Mauer; S Kupcho-Sandberg; D M Brown Journal: Proc Natl Acad Sci U S A Date: 1983-04 Impact factor: 11.205