Effect of sex steroids on the circulating levels of alpha 2-macroglobulin in injured rats.
The effect of sex steroids on the plasma levels of alpha 2-macroglobulin (alpha 2-M) was investigated to explain the sexual dimorphism observed in response to the injury caused by ip administration of 5 micrograms endotoxin. Mean serum alpha 2-M concentrations were lower in female (46.82 +/- 8.10 arbitrary units) than in male injured rats (82.94 +/- 9.22 arbitrary units). A reduction of plasma alpha 2-M levels was observed after orchidectomy, and the administration of 1 mg testosterone to the same animals increased the response. The same response pattern was observed in ovariectomized rats under the same treatment. The response of androgenized rats (78.93 +/- 12.81 arbitrary units) to injury was similar to the male response. These results suggest the importance of testosterone as the major determinant of this sex-dependent response.
Hirai
C Y
CY
Departamento de Fisiologia, Escola Paulista de Medicina, São Paulo, SP, Brasil.
Limãos
E A
EA
D000210:Acute-Phase Reaction / Q000209:etiology*; D000818:Animals; D004731:Endotoxins / Q000494:pharmacology; D005260:Female; D012739:Gonadal Steroid Hormones / Q000494:pharmacology*; D008297:Male; D009919:Orchiectomy; D010052:Ovariectomy; D051381:Rats; D011919:Rats, Inbred Strains; D012727:Sex Characteristics; D000511:alpha-Macroglobulins / Q000378:metabolism*
D004731:Endotoxins; D012739:Gonadal Steroid Hormones; D000511:alpha-Macroglobulins