DIVERSITY OF VASCULAR REACTIVITY AND THE TREATMENT RESPONSE IN DIABETIC, HYPERTENSIVE, HYPERLIPIDEMIC, AND HEALTHY RATS SUBJECTED TO HEMORRHAGIC SHOCK.

Abstract

The current diagnosis and treatment guidelines for severe trauma and shock are all for healthy population. Few studies focused on the pathophysiological features and treatments in metabolic diseases after severe trauma and shock. Vascular reactivity is significantly decreased after severe trauma and shock. Improving the vascular reactivity with arginine vasopressin (AVP) and phorbol-12 myristate-13-acetate (PMA) is beneficial to trauma and shock. Whether the cardiovascular function and treatment responses have the own features in hypertensive, diabetic, and hyperlipidemic patients after traumatic hemorrhagic shock is not known. Using hypertensive, diabetic, and hyperlipidemic and healthy rats, we compared the change patterns in cardiovascular function including vascular reactivity, tissue perfusion, and the hemodynamics after hemorrhagic shock and their responses to AVP, PMA, and common antishock agents including dopamine and norepinephrine. A same degree of hemorrhagic shock (40% hemorrhage or mean arterial pressure maintained at 40 mm Hg for 2 h) resulted in a more obvious decrease in vascular reactivity, hemodynamics, tissue perfusion, and mitochondrial function of liver and kidney in hypertensive, diabetic, and hyperlipidemic rats, and a more rapidly natural death than in healthy rats. The effectiveness of AVP and PMA in these diseased rats was lower than in healthy rats. The effective dosage of common antishock agents including norepinephrine, dopamine, and AVP in healthy rats was wider than that in these diseased rats. Among the antishock agents used in the current study, AVP had the best effect in improving animal survival and vascular reactivity both in healthy and in diseased rats. These findings suggest that hypertensive, diabetic, and hyperlipidemic rats have a worse vascular reactivity and organ function than the healthy rats after traumatic hemorrhagic shock, which result in the worse treatment responses and effects to vasoactive agents. Lower dose of AVP can be recommended as the first-line antishock agents for these diseased rats.