Benjamin Hake ACF Abstract FY12

"Changes in vascular reactivity of mesenteric arteries following hyperbaric oxygen treatment"

American Physiological Society Experimental Biology 2012

The objective of this study was to evaluate the changes in vascular reactivity of mesenteric arteries resulting from hyperbaric oxygen treatment. It was hypothesized that hyperbaric oxygen treatment alters vascular reactivity in mesenteric arteries. Arteries from porcine mesenteries were dissected and then subjected to a 2-hour hyperbaric treatment in 100% oxygen, 100% nitrogen, or ambient air (1.75 ATA). An additional control included vessels exposed to ambient air at 1 ATA. Immediately following, arteries were mounted in isolated organ baths and passively loaded with 7 grams of tension. Following a 1-hour equilibration in Krebs-Henseleit solution arteries were treated with potassium chloride (KCl; 15  60 mM) to assess viability. Subsequently, arteries were treated with increasing concentrations of phenylephrine (10-7  10-4 M) then sodium nitroprusside (10-7  10-4 M) to measure changes in vascular reactivity. KCl-induced vasoconstriction was significantly increased in response to hyperbaric oxygen treatment compared to ambient air control (1 ATA). Treatment with hyperbaric oxygen augmented vascular responses to phenylephrine and sodium nitroprusside relative to nitrogen but not ambient air. The results from these studies provide insight into the vascular effects of hyperbaric oxygen treatment.