Arterial blood gases, electrolytes, and metabolic indices associated with hemorrhagic shock: inter- and intrainbred rat strain variation

• Published in: Journal of applied physiology (1985) 2013-05, Vol.114 (9), p.1165-1173
• Main Authors: Rose, Rajiv, Kheirabadi, Bijan S, Klemcke, Harold G
• Format: Article
• Language: English
• Subjects: Analysis of Variance; Animals; Correlation analysis; Disease Models, Animal; DNA methylation; Electrolytes; Electrolytes - blood; Epigenesis, Genetic; Epigenetics; Gases - blood; Hemorrhage; Hypovolemia - blood; Hypovolemia - genetics; Male; Rats; Rats, Inbred BN; Rats, Inbred Dahl; Rats, Inbred Lew; Rats, Inbred Strains - blood; Rats, Inbred Strains - genetics; Rodents; Shock, Hemorrhagic - blood; Shock, Hemorrhagic - genetics; Species Specificity; Veins & arteries
• ISSN: 8750-7587; 1522-1601
• DOI: 10.1152/japplphysiol.01293.2012

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 = 8-10/strain) 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 (Δ) during hemorrhage, and these changes differed among strains (P 10%), strain-specific CVs, and low intraclass correlation coefficients (rI < 0.5) defined the large intrastrain ABM variation that exceeded interstrain variation for most ABM. These results suggest that some ABM (K(+), 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.