ENHANCED IMMUNE-RESPONSES IN FEMALES, AS OPPOSED TO DECREASED RESPONSES IN MALES FOLLOWING HEMORRHAGIC-SHOCK AND RESUSCITATION

Although haemorrhagic shock produces immunodepression in both humans a nd experimental animals, no information is available concerning gender differences in the immune and endocrine response to shock. To study t his, male and female (proestrus and diestrus) C3H/HeN mice (25 g body weight) were bled and maintained at a mean arterial blood pressure of 35 +/- 5 mmHg for 1 h and then adequately resuscitated. The animals we re killed at 2 h after resuscitation to obtain splenocytes, macrophage s (M phi, peritoneal and splenic), as well as whole blood. IL-l releas e by M phi, splenocyte proliferative capacity and splenocyte IL-3 rele ase in female mice was significantly increased. Male mice, however, sh owed decreased release of all interleukins (IL-1, 2, 3, 6) as well as splenocyte proliferative capacity after shock. Plasma corticosterone l evels decreased in proestrus female mice, as opposed to increased leve ls in males following shock. Corticosterone mag therefore, be in part responsible for the observed gender differences. To the authors' knowl edge, this is the first study which shows that immune responsiveness i n female mice is enhanced after haemorrhagic shock, as opposed to decr eased responsiveness in males. Thus, unlike males which exhibit increa sed susceptibility to sepsis/infections, females should be able to bet ter tolerate the deleterious effects of shock. (C) 1996 Academic Press Limited.