The American journal of physiology
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Palmitate metabolism was determined in isolated perfused hearts containing elevated levels of coenzyme A (CoA). CoA levels were elevated by perfusing hearts with Krebs-Henseleit buffer containing 0.1 mM cysteine, 0.2 mM dithiothreitol, 15 microM pantothenic acid, and no energy substrate. After 45 min, CoA levels had increased from 537 +/- 14 to 818 +/- 44 nmol/g dry wt. ⋯ The specific activity of this pool of fatty acid was similar in both control hearts and hearts containing elevated CoA. Thus dilution of the total cellular [14C]acyl carnitine by triacylglycerol hydrolysis was not sufficient to account for the decrease in [U-14C]palmitate oxidation. The possibility that a small pool of rapidly turning over acyl carnitine becomes dilated is discussed.(ABSTRACT TRUNCATED AT 250 WORDS)
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To evaluate rapid fluid shifts after graded hemorrhage in splenectomized animals, four pigs and two dogs were bled 15-23 ml/kg body wt in steps of 2.2-6.0 ml/kg. Arterial blood density (BD), mean arterial pressure (MAP), and central venous pressure (CVP) were recorded continuously, and arterial plasma density (PD) and hematocrit (Hct) were determined from blood samples. Erythrocyte density was computed from PD, BD, and Hct. ⋯ Calculations suggest that either the inward-shifted fluid has a higher density than normal ultrafiltrate and/or there is a rise of the whole-body-to-large vessel Hct (F cell ratio). The rapid fluid replacement ranged from 5.8 +/- 0.8 to 10.6 +/- 2.0% of the initial plasma volume, or one-fifth to one-third of the lost volume with a 20% hemorrhage. Transvascular fluid shifts can be monitored with continuous high-precision blood densitometry.