Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0018801 (heart failure)
 72,216 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Urodilatin is a recently discovered natriuretic peptide [ANP-(95-126)] of renal origin, with a primary structure similar to ANP-(99-126). However, urodilatin is not biologically inactivated by renal endopeptidase, and it is a more potent natriuretic agent than ANP-(99-126). The present study was carried out to investigate the renal and systemic effects of urodilatin in rats before and after the induction of congestive heart failure (CHF) by creation of an aortocaval fistula (ACF). Administration of urodilatin in incremental doses (0.75-12 micrograms.kg-1.h-1) to Inactin-anesthetized sham-operated control rats resulted in dose-dependent increases in urine flow, glomerular filtration rate (GFR), excretion of guanosine 3',5'-cyclic monophosphate (cGMP), sodium, and potassium, and a significant decrease in mean arterial blood pressure. In rats with ACF the baseline values for GFR and sodium excretion were significantly lower than in control rats. Urodilatin infusion in rats with ACF led to significant increases in urine flow and sodium excretion, but the absolute levels of diuresis and natriuresis were significantly lower in rats with CHF than in normal rats. When urodilatin was infused into rats with ACF pretreated with neutral endopeptidase inhibitor (NEP-I; SQ-28,063 at a dose of 40 mg/kg iv), the absolute urine flow and sodium excretion were not different from that obtained in control rats. Thus the attenuated natriuretic and diuretic response to ANP-(99-126) in heart failure was not observed with urodilatin.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Renal and systemic effects of urodilatin in rats with high-output heart failure. 153

Experiments were performed to test the postulate that exercise training (ExT) improves the blunted renal excretory response to acute volume expansion (VE), in part, by normalizing the neural component of the volume reflex typically observed in chronic heart failure (HF). Diuretic and natriuretic responses to acute VE were examined in sedentary and ExT groups of rats with either HF or sham-operated controls. Experiments were performed in anesthetized (Inactin) rats 6 wk after coronary ligation surgery. Histological data indicated that there was a 34.9 +/- 3.0% outer and 42.5 +/- 3.2% inner infarct of the myocardium in the HF group. Sham rats had no observable damage to the myocardium. In sedentary rats with HF, VE produced a blunted diuresis (46% of sham) and natriuresis (35% of sham) compared with sham-operated control rats. However, acute VE-induced diuresis and natriuresis in ExT rats with HF were comparable to sham rats and significantly higher than sedentary HF rats. Renal denervation abolished the salutary effects of ExT on renal excretory response to acute VE in HF. Since glomerular filtration rates were not significantly different between the groups, renal hemodynamic changes may not account for the blunted renal responses in rats with HF. Additional experiments confirmed that renal sympathetic nerve activity responses to acute VE were blunted in sedentary HF rats; however, ExT normalized the renal sympathoinhibition in HF rats. These results confirm an impairment of neurally mediated excretory responses to acute VE in rats with HF. ExT restored the blunted excretory responses as well as the renal sympathoinhibitory response to acute VE in HF rats. Thus the beneficial effects of ExT on cardiovascular regulation in HF may be partly due to improvement of the neural component of volume reflex.
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PMID:Exercise training improves renal excretory responses to acute volume expansion in rats with heart failure. 1682 36

Despite the classically held belief of an "all-or-none" activation of the sympathetic nervous system, differential responses in sympathetic nerve activity (SNA) can occur acutely at varying magnitudes and in opposing directions. Sympathetic nerves also appear to contribute differentially to various disease states including hypertension and heart failure. Previously we have reported that sedentary conditions enhanced responses of splanchnic SNA (SSNA) but not lumbar SNA (LSNA) to activation of the rostral ventrolateral medulla (RVLM) in rats. Bulbospinal RVLM neurons from sedentary rats also exhibit increased dendritic branching in rostral regions of the RVLM. We hypothesized that regionally specific structural neuroplasticity would manifest as enhanced SSNA but not LSNA following activation of the rostral RVLM. To test this hypothesis, groups of physically active (10-12 weeks on running wheels) or sedentary, male Sprague-Dawley rats were instrumented to record mean arterial pressure, LSNA and SSNA under Inactin anesthesia and during microinjections of glutamate (30 nl, 10 mM) into multiple sites within the RVLM. Sedentary conditions enhanced SSNA but not LSNA responses and SSNA responses were enhanced at more central and rostral sites. Results suggest that enhanced SSNA responses in rostral RVLM coincide with enhanced dendritic branching in rostral RVLM observed previously. Identifying structural and functional neuroplasticity in specific populations of RVLM neurons may help identify new treatments for cardiovascular diseases, known to be more prevalent in sedentary individuals.
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PMID:Altered Differential Control of Sympathetic Outflow Following Sedentary Conditions: Role of Subregional Neuroplasticity in the RVLM. 2748 5