Adipocytes secrete several biologically active substances that are presumed to be involved in obesity-related hypertension. There are no reports that deal with the relationship between plasma adiponectin concentration and blood pressure (BP). To evaluate the role of adiponectin in essential hypertension 33 patients with essential hypertensive (EHP) (12 women, 21 men) and 33 body mass index-matched normotensive healthy subjects (NHS) (13 women, 20 men) were studied. In EHP plasma adiponectin concentration was significantly lower than in NHS (9.1 +/- 4.5 v 13.7 +/- 5.2 microg/mL, respectively). In all subjects a significant negative correlation was found between plasma adiponectin concentration and mean, systolic, and diastolic BP, suggesting that adiponectin contributes to the clinical course of essential hypertension.
: Interventions to block the renin-angiotensin system (RAS) halt the progression of renal lesions in renal damage models. It has recently also been reported that established glomerulosclerosis can be reversed by pharmacologic blockade of the RAS. It was the aim of this study to confirm that high doses of angiotensin-converting enzyme (ACE) inhibitors reverse established glomerulosclerosis and to extend the findings by providing quantitative information on glomerular geometry, podocytes and other glomerular cells, renal vessels and tubulointerstitial tissue. Male Sprague Dawley rats were subjected to subtotal surgical renal ablation (SNX) (n = 27) or sham operation (n = 31) and fed using a pair-feeding protocol. Eight weeks after surgery, rats were either sacrificed or allocated to two arms: enalapril treatment (48 mg/kg body wt per day administered in the drinking fluid for 4 wk) or no treatment. Renal morphology was evaluated after 8 or 12 wk, respectively, by stereology in tissue fixed by pressure-controlled perfusion. Both systolic BP and albumin excretion rate were significantly higher in SNX compared with sham-operated controls. They were significantly reduced in SNX after delayed enalapril treatment. The glomerulosclerosis (GSI), tubulointerstitial (TII), and vascular (VI) damage indices were significantly higher in all SNX groups than in sham-operated controls. At the end of the experiment (12 wk after SNX) GSI, TII, and VI were significantly lower in SNX with delayed enalapril treatment (0.77 ± 0.18, 0.63 ± 0.19 and 0.43 ± 0.16, respectively) compared with untreated SNX (1.64 ± 0.14, 1.16 ± 0.34 and 0.67 ± 0.29, respectively). GSI, TII, and VI were also significantly lower in SNX with delayed enalapril treatment compared with SNX sacrificed without treatment 8 wk after SNX. The same was true for glomerular volume. The number of podocytes was not affected by SNX, but podocyte volume was increased. Both indices remained unaffected by treatment. The numbers of cells within the mesangium and endothelial cells per glomerulus were significantly lower in SNX after delayed enalapril treatment compared with untreated SNX. These results strongly suggest regression of preexisting lesions, i.e., glomerular, tubular, and vascular remodeling as well as reversal of glomerular hypertrophy by ACE inhibitor treatment. The study confirms that high-dose ACE inhibitor treatment causes partial reversal of glomerular as well as interstitial lesions in subtotally nephrectomized rats. E-mail: kerstin.amann@patho.imed.uni-erlangen.de
1 January 2007 in Clinical Journal of the American Society of Nephrology
Coronary calcification is a potent predictor of cardiac events. In patients with chronic renal disease, both prevalence and intensity of coronary calcification are increased. It has remained uncertain whether it is the intima of the coronaries or the media that is calcified and whether the morphologic details of calcified plaques differ between renal and nonrenal patients. Autopsy samples of coronaries were obtained from standard sites in 23 renal and 23 age- and gender-matched nonuremic patients. Specimens were examined using light and electron microscopy, immunohistochemistry, backscatter imaging, and x-ray analysis. In coronaries, calcified plaques occupied a similar proportion of the intima area in renal versus nonrenal patients (17.3 ± 11.9 versus 18.1 ± 11.9%) but occupied a significantly higher proportion of the media (16.6 ± 10.6 versus 3.8 ± 2.31%). Expression of the proteins osteocalcin, C-reactive protein, TGF-β, and collagen IV was significantly more intensive around coronary plaques of renal compared with nonrenal patients. The non–plaque-bearing intima of renal patients showed minimal staining for fetuin, but fetuin staining was seen surrounding calcified plaques. In addition, more pronounced deposition of C5b-9 was found around coronary plaques of renal patients, and glycophorin deposition pointed to more past intraplaque hemorrhage in renal patients. Calcification by electron backscatter analysis is more intense in the coronary media, but not if the intima is more intense in renal compared with nonrenal patients. A more marked inflammatory response in renal patients is suggested by more frequent presence and greater intensity of markers of inflammation.