Effect of estradiol on endotoxin-induced changes in steroid hormone levels and lethality in male rats.
We examined the effect of exogenous estradiol on the changes in serum steroid hormone levels induced by a nonlethal dose of Escherichia coli endotoxin in male rats and the deaths due to nonlethal and lethal doses of endotoxin. Injection of estradiol 5 min before a nonlethal dose of endotoxin changed the serum sex steroid hormone response of male rats to endotoxin. The serum estrogen concentrations of estradiol + endotoxin-treated rats decreased by 50% (P < 0.001), while those of the endotoxin-treated rats increased (2- to 5-fold). The serum androgen concentrations of estradiol + endotoxin-treated rats did not change significantly, while those of endotoxin-treated rats dropped to 30-40%, P < 0.001. Exogenous estradiol also appeared to influence the percentage of endotoxin-induced deaths in a dose-dependent manner. It reduced the number of deaths induced by nonlethal (2 mg/kg) dose of endotoxin but increased the number of deaths induced by a highly lethal dose (8 mg/kg). These results, together with the known relationships between estrogen and the immune response, suggest that estrogens affect the course of septic shock in a complex fashion and may have either protective or deleterious effect.
Christeff
N
N
U.224, INSERM affiliée au CNRS, Facilté de Médecine X. Bichat, Paris, France.
Auclair
M C
MC
Thobie
N
N
Fertil
B
B
Carli
A
A
Nunez
E A
EA
D000728:Androgens / Q000097:blood*; D000818:Animals; D004347:Drug Interactions; D004731:Endotoxins / Q000008:administration & dosage / Q000494:pharmacology / Q000633:toxicity*; D004926:Escherichia coli; D004958:Estradiol / Q000097:blood* / Q000494:pharmacology*; D007700:Kinetics; D008297:Male; D051381:Rats; D017208:Rats, Wistar
D000728:Androgens; D004731:Endotoxins; D004958:Estradiol