Laser Correction of Delayed Posthypoxic Encephalopathies (Experimental Study

Abstract

Objective: to study whether posthypoxic brain dysfunctions may be corrected by low-intensity laser irradiation an hour after hypovolemic hypotension at late postresuscitation stages (following 30 days). Material and methods. Experiments were carried out on high-anxious male albino rats weighing 280—300 g. The study model was one-hour hypovolemic hypotension (blood pressure 40 mm Hg), followed by blood reinfusion. The integrative brain function was evaluated from the indices of the rat orientative-trying behavior in the elevated cross labyrinth test. The depressive component of the rats’ behavior was examined in the forced swimming test. Plasma norepinephrine levels were measured. Laser irradiation was performed 30 days after blood reinfusion. Results. Laser irradiation used at late postresuscitation stages leads to the normalization of plasma norepinephrine levels, the reduction of anxiety in the rats, and their improved orientative-trying behavior. Conclusion. The positive impact of laser irradiation on the rat orientative-trying behavior is associated with its anxiolytic effect, in which the recovery of autonomic homeostasis plays a considerable role. Key words: blood loss, postresuscitative period, behavior, laser, posthypoxic encephalopathy, norepinephrine.