The relationship between post-burn increases in peripheral resistance and vasopressin

Area of Science:

• Physiology
• Pharmacology
• Burn Medicine

Background:

• Thermal injury, such as severe burns, triggers physiological responses that can impact cardiovascular function.
• Vasopressin is a hormone known to cause vasoconstriction and its role in burn shock is not fully understood.

Purpose of the Study:

• To investigate the role of vasopressin in the increased peripheral resistance observed after a severe burn.
• To evaluate the efficacy of a vasopressin V-1 receptor antagonist in mitigating burn-induced cardiovascular changes.

Main Methods:

• An experimental model using dogs with a 15% total body surface flame burn was employed.
• Animals received either a vasopressin V-1 receptor antagonist (d(CH2)5Tyr(Me)AVP) or no treatment prior to burn.
• Peripheral resistance, cardiac output, mean arterial blood pressure, and plasma vasopressin levels were measured post-burn.

Main Results:

• Administration of the vasopressin antagonist significantly reduced the increase in peripheral resistance compared to controls.
• Peripheral resistance increased from baseline to 128.0 +/- 20.3 units immediately post-burn in untreated animals.
• Plasma vasopressin levels significantly increased post-burn, correlating with elevated peripheral resistance.

Conclusions:

• Severe thermal injury leads to a significant release of vasopressin.
• The increased peripheral resistance following burns is, in part, mediated by the vasoconstrictor action of released vasopressin.
• Blocking V-1 receptors may be a therapeutic strategy to manage burn-induced cardiovascular dysfunction.