L. Gabriel Navar

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The aims of this study were to delineate the relative contribution of angiotensin II (ANG II) subtype 1A (AT1A) and 1B (AT1B) receptors to the development of two-kidney, one-clip (2K1C) Goldblatt hypertension in mice, to examine if increased nitric oxide synthase (NOS) activity counteracts the vasoconstrictor influences of ANG II in 2K1C hypertensive mice,(More)
Intrarenal angiotensin II (Ang II) is regulated by several complex processes involving formation from both systemically delivered and intrarenally formed substrate, as well as receptor-mediated internalization. There is substantial compartmentalization of intrarenal Ang II, with levels in the renal interstitial fluid and in proximal tubule fluid being much(More)
L-type Ca2+ channels predominantly influence preglomerular arterioles, but there is less information regarding the role of T-type Ca2+ channels in regulating the renal microvasculature. We compared the effects of T- and L-type channel blockade on afferent and efferent arterioles using the in vitro blood-perfused juxtamedullary nephron preparation. Single(More)
In human kidneys, the mechanisms underlying angiotensinogen (AGT) augmentation by interleukin 6 (IL-6) are poorly understood and the only information available is in HK-2, immortalized human renal proximal tubular epithelial cells. Therefore, the present study was performed to elucidate the effects of IL-6 on AGT expression in primary cultured human renal(More)
Recent studies have indicated that changes in intrarenal nitric oxide (NO) production participate in mediating arterial pressure-induced changes in urinary sodium excretion. Until recently, however, the means to measure changes in intrarenal NO activity in vivo have not been available. For the present study, changes in renal tissue NO activities were(More)
Oxidative stress in the central nervous system mediates the increase in sympathetic tone that precedes the development of hypertension. We hypothesized that by transforming Angiotensin-II (AngII) into Ang-(1-7), ACE2 might reduce AngII-mediated oxidative stress in the brain and prevent autonomic dysfunction. To test this hypothesis, a relationship between(More)
Angiotensin (Ang) II-infused hypertensive rats exhibit increases in renal angiotensinogen mRNA and protein, as well as urinary angiotensinogen excretion in association with increased intrarenal Ang II content. The present study was performed to determine if the augmentation of intrarenal angiotensinogen requires activation of Ang II type 1 (AT1) receptors.(More)
Distal nephron renin may provide a possible pathway for angiotensin (Ang) I generation from proximally delivered angiotensinogen. To examine the effects of Ang II on distal nephron renin, we compared renin protein and mRNA expression in control and Ang II-infused rats. Kidneys from sham (n=9) and Ang II-infused (80 ng/kg per minute, 13 days, n=10)(More)
Chronic elevations of circulating angiotensin II (Ang II) cause sustained hypertension and enhanced accumulation of intrarenal Ang II by an AT1 receptor-dependent process. The present study tested the hypothesis that chronic elevations in circulating Ang II regulate AT1 mRNA and protein expression in a tissue-specific manner. Sprague-Dawley rats were(More)