James D. Barrett

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The observation that nuclei from hepatic tissue exhibit specific angiotensin II (Ang II) binding led us to explore whether Ang II modulates mRNA in general, mRNA specific for renin system components, or both. Nuclei from hepatic tissue exhibited a single high-affinity (Kd = 0.4 nmol/L) Ang II-specific binding site, which was associated with increased RNA(More)
Ten male patients with essential hypertension were studied on a constant diet (100 mEq of sodium daily) while on placebo, immediately following a 20-mg oral dose of nitrendipine, and during 1 week of nitrendipine therapy (10 mg twice daily). After 2 weeks of outpatient follow-up on 20-40 mg nitrendipine daily, the patients were readmitted and restudied with(More)
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(More)
OBJECTIVES To investigate the influence of angiotensin II (All) receptors in isolated hepatic nuclei on other genes regulated by All and to determine whether the function of these intracellular receptors is influenced by alterations in the endocrine renin system. METHODS Nuclei were isolated from hepatic tissue of normal and bilaterally nephrectomized or(More)
Recent studies suggest the presence of local angiotensin generating system in the kidney. By using in situ hybridization technique, mRNA for angiotensinogen has been shown to be present in the proximal tubule. In the present study, we have attempted to examine the production of angiotensinogen and renin-like activity by the proximal convoluted (PCT) and(More)
In humans, blockade of the renin-angiotensin system with angiotensin converting-enzyme inhibitors (ANG CEI) prevents the rise in blood pressure associated with the administration of recombinant human erythropoietin (rhEPO). This study was conducted to determine whether rhEPO elevates blood pressure in normal Wistar rats and whether the renin-ANG system is(More)
The presence of a renin-angiotensin system in the central nervous system (CNS) has been demonstrated by several investigators, but little is known regarding the origin of its components. In this study we have compared the immunological and physical-chemical nature of angiotensinogen in plasma and cerebrospinal fluid (CSF) of human subjects and explored(More)
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(More)
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(More)