Basic metabolic rate in emotional stress: Its potential influence on cochlear function

Using a model previously described, prolonged emotional stress was induced in guinea pigs. Under this condition, arterial blood gases, blood glucose level, PO2 and PCO2 in the expired air, and the heat irradiated by the animals were measured and compared to those of the anesthetized guinea pigs. From the present study, two important findings should be mentioned. First, the metabolic rate of the animals under stress was 30% higher than in the anesthetized group. Second, the arterial PO2 level of the animals under stress was significantly lower than that in the anesthetized ones. Evaluating the noxious effect of severe and/or prolonged emotional stress, one should not neglect the increased oxygen demand resulting from the high metabolic rate of the subject. This factor, together with the decreased arterial blood PO2 level, reinforce the hypoxic effects on the cochlear function, caused by the vasoconstriction of the labyrinthine vessels.