TESTOSTERONE - THE CRUCIAL HORMONE RESPONSIBLE FOR DEPRESSING MYOCARDIAL-FUNCTION IN MALES AFTER TRAUMA-HEMORRHAGE

Objective To determine whether testosterone depletion in males before trauma-hemorrhage has any salutary effects on cardiac performance afte r hemorrhage and resuscitation. Summary Background Data Studies indica te that castration of male mice before trauma-hemorrhage prevents the immunodepression seen after hemorrhage and resuscitation. However, the effect of precastration on cardiac performance under such conditions remains unknown. Methods Male rats were castrated or sham-castrated 14 days before the experiment. After laparotomy (i.e., induction of trau ma), the rats were bled to and maintained at a mean arterial pressure of 40 mm Hg until 40% of the maximal shed volume was returned in the f orm of Ringer's lactate solution. The animals were then resuscitated w ith four times the shed blood volume with Ringer's lactate solution ov er 60 minutes. Heart performance was measured using a left ventricular catheter connected to an in vivo heart performance analyzer. indices of left ventricular performance (i.e., maximal rate of the pressure in crease [+dP/dt(max)] and decrease [-dP/dt(max)]) were measured up to 4 hours after trauma, hemorrhagic shock, and resuscitation. Results In sham-castrated animals, trauma-hemorrhage and resuscitation decreased the in vivo heart performance as evidenced by the reduced values of +d P/dt(max) and -dP/dt(max). Precastrated animals, however, showed signi ficantly higher values of +dP/dt(max) and -dP/dt(max) than sham-castra ted animals after trauma-hemorrhage and resuscitation. Conclusions Tes tosterone antagonism in males might be an effective approach for maint aining myocardial function after adverse circulatory conditions. Altho ugh testosterone depletion in male trauma victims is neither practical nor advocated, testosterone receptor blockade after trauma may repres ent a novel and useful adjunct for maintaining normal myocardial perfo rmance under those conditions.