Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.4.23.15 (renin)
 35,795 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In 5 total artificial heart (TAH)-bridge-to-transplant (BTT) patients production and secretion of atrial natriuretic factor (ANF)1 was studied before, during, and after TAH implantation. Bridging periods lasted between 9 and 28 days. Atrial biopsies were taken during implantation, and after TAH explantation for histologic and histochemical investigations to evaluate differences in morphology and ANF-content of the specific atrial granules. Plasma concentrations of ANF (pANF), aldosterone (PAC) and renin (PRC) were measured daily, as were hemodynamic parameters. In the preoperative state, pANF was always markedly elevated, while during TAH bridging, pANF remained moderately elevated with fluctuations. A positive correlation between pANF levels and right atrial pressure (RAP) was seen in all patients (p less than 0.05). Slight correlation was also observed between pANF and left atrial pressure (LAP), but no correlation was seen between pANF and systemic blood pressure, and no consistent pattern was seen in the plasma concentrations of either renin or aldosterone. After heart transplantation (HTX), which was performed in 3 patients, pANF levels were significantly higher than during TAH, and continued to show a positive correlation with RAP. From our data, we conclude that ANF production sites and secretory mechanisms remain intact during TAH-bridging, although upon implantation of a TAH, the remaining atria are deprived of all coronary blood supply and most autonomic innervation.
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PMID:Atrial natriuretic factor production and secretion during clinical total artificial heart-bridge-to-transplantation. 253 32

Orthotopic heart transplantation results in cardiac denervation that can disrupt the normal regulation of hydromineral balance. This study compared the exercise-induced variations in plasma osmolality; atrial natriuretic peptide (ANP), arginine vasopressin (AVP), norepinephrine (NE), epinephrine (E), and dopamine (DA) concentrations; and plasma renin activity (PRA) of six cardiac transplant recipients (HTX) and six healthy age-matched controls (C) submitted to graded upright maximal cycling. Venous blood samples were obtained at rest, at submaximal (70% O2 uptake) and peak exercise, and after 10 and 30 min of sitting recovery. Peak O2 uptake was not different between groups despite lower maximal heart rate in HTX (136 +/- 6 vs. 183 +/- 9 beats/min). Baseline plasma ANP and PRA were higher in HTX (203 +/- 55 pg/ml and 29.9 +/- 7.4 ng.ml-1 x h-1) than in C (71 +/- 17 pg/ml and 5.4 +/- 0.96 ng.ml-1 x h-1); AVP was lower in HTX than in C (1.1 +/- 0.3 vs. 3.2 +/- 0.8 pg/ml; P < 0.05); and circulating E, NE, and DA were not different between groups. Exercise resulted in more marked increases in HTX than in C for ANP (300 vs. 100%), AVP (2,000 vs. 300%), NE (860 vs. 500%), and DA (611 vs. 187%) but not for PRA and a higher E response in C than in HTX (455 vs. 1,258%). These observations confirm that the potential for ANP release to central volume loading is independent of intact cardiac innervation. The exaggerated AVP response in HTX could, however, reflect the absence of inhibitory influences consecutive to denervation.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Fluid-regulating and sympathoadrenal hormonal responses to peak exercise following cardiac transplantation. 817 10