Pilot studies to demonstrate that intestinal mucosal afferent nerves are functionally linked to visceral adipose tissue.

Dietary capsaicin reduces rodent visceral fat weight. We tested the hypothesis that intact intestinal mucosal afferent nerve function is necessary for fat deposition in visceral adipose tissue sites. Rats were treated daily for 2 weeks with intragastric (chronic treatment) vehicle or capsaicin.

Insulin stimulates endogenous angiotensin II production via a mitogen-activated protein kinase pathway in vascular smooth muscle cells.

Objective: The present study was designed to determine the effects of insulin on cytosolic angiotensin II production and proliferation in cultured rat vascular smooth muscle cells.

Design And Methods: Vascular smooth muscle cells were incubated with insulin for 48 h. Cytosolic angiotensin I and II were determined by radioimmunoassays of purified cell homogenates.

Insulin and insulin-like growth factor-I promotes angiotensinogen production and growth in vascular smooth muscle cells.

Background: Circulating insulin and insulin-like growth factor-I (IGF-I) levels are increased in patients with hypertension and insulin resistance. Since both hormones are known to have cell growth-promoting effects, they may contribute to the progression of vascular hypertrophy in patients with insulin resistance. Insulin-mediated activation of the vascular renin-angiotensin system (RAS) stimulates growth in cultured rat vascular smooth muscle cells (VSMC).

Erythropoietin upregulates angiotensin receptors in cultured rat vascular smooth muscle cells.

Objective: Plasma renin is not elevated in recombinant human erythropoietin (rhEPO)-induced hypertension but angiotensin converting enzyme inhibitors reduce blood pressure in both human and animal studies. Since rhEPO elevates renin and angiotensinogen messenger RNAs in angiotensin II target tissues such as the aorta, we explored the actions of rhEPO on renin-angiotensin system-related gene transcription of cultured rat vascular smooth muscle cells.

Design And Methods: To separate direct actions of rhEPO from those mediated secondarily by potential activation of the renin-angiotensin system, vascular smooth muscle cells were cultured with rhEPO and enalapril to inhibit the angiotensin converting enzyme and losartan to inhibit angiotensin II type 1 receptors.

Insulin-mediated growth in aortic smooth muscle and the vascular renin-angiotensin system.

Insulin has been shown to directly affect blood vessel tone and to promote vascular hypertrophy, but the mechanism of these actions remains uncertain. Because angiotensin I (Ang I)-converting enzyme inhibitors have been shown to improve insulin action and to impede the progression of vascular hypertrophy in hypertensive animal models, it is possible that the vascular properties of insulin may be mediated through the tissue renin-angiotensin system (RAS). To evaluate this relationship, we first investigated the effect of insulin on components of the RAS using cultured rat vascular smooth muscle cells (VSMCs).