Arterial Blood Gases, Electrolytes and Metabolic Indices Associated with Hemorrhagic Shock: Inter-and Intrainbred Rat Strain Variation
ARMY INST OF SURGICAL RESEARCH FORT SAM HOUSTON TX
Pagination or Media Count:
We have previously shown interstrain variation indicating a genetic basis, and intrastrain variation in survival time after hemorrhage STaH among inbred rat strains. To assist in understanding physiological mechanisms associated with STaH, we analyzed various arterial blood measures ABM pH, PaCO2, oxygen content, sodium, potassium, glucose, bicarbonate, base excess, total CO2, and ionized calcium in inbred rats. Rats from five inbred strains n 8-10strain were catheterized and, 24 h later, subjected to a conscious, controlled, 47 hemorrhage. ABM were measured at the start initial and end final of hemorrhage. Inter- and intrainbred strain variations of ABM were quantified and compared, and correlations of ABM with STaH were determined. All final ABM values and some initial ABM values were different among strains. Most ABM changed delta during hemorrhage, and these changes differed among strains P 0.03. Some strain-dependent correlations r 0.7 P 0.05 existed between deltaABM and STaH e.g., BNMcwi, deltaKexpn , r -0.84. Dark Agouti rats longest STaH had the smallest deltaPaCO2, deltaHCO3-, and deltabase excess, and the highest final glucose. High coefficients of variation CVs, 10, strain-specific CVs, and low intraclass correlation coefficients rsub t 0.5 defined the large intrastrain ABM variation that exceeded interstrain variation for most ABM. These results suggest that some ABM Kexpn , PaCO2, glucose, oxygen content could predict subsequent STaH in an inbred rat strain-dependent manner. We speculate that whereas genetic differences may be responsible for interstrain variation, individual-specific epigenetic processes e.g., DNA methylation may be partly responsible for both inter- and intrastrain ABM variation.
- Anatomy and Physiology
- Medicine and Medical Research