title: Gender differences in small intestinal perfusion following trauma hemorrhage: the role of endothelin-1.
abstract: Although gender differences in intestinal perfusion exist following trauma-hemorrhage (T-H), it remains unknown whether endothelin-1 (ET-1) plays any role in these dimorphic responses. To study this, male, proestrus female (female), and 17 beta-estradiol (E2)-treated male rats underwent midline laparotomy, hemorrhagic shock (blood pressure 40 mmHg, 90 min), and resuscitation (Ringer lactate, 4X shed blood volume, 1 h). Two hours thereafter, intestinal perfusion flow (IPF) was measured using isolated intestinal perfusion. The IPF in sham-operated males was significantly lower than those in other groups and decreased markedly following T-H. In contrast, no significant decrease in IPF was observed in females and E2 males following T-H. The lower IPF in sham-operated males was significantly elevated by ET(A) receptor antagonist (BQ-123) administration and was similar to that seen in sham-operated females. The decreased IPF in males after T-H was also attenuated by BQ-123 administration. The intestinal ET-1 levels in sham-operated males were significantly higher than in other groups. Although plasma and intestinal ET-1 levels increased significantly after T-H in all groups, they were highest in males. Plasma E2 levels in females and E2 males were significantly higher than in males; however, they were not affected by T-H. There was a negative correlation between plasma ET-1 and E2 following T-H. Thus ET-1 appears to play an important role in intestinal perfusion failure following T-H in males. Because E2 can modulate this vasoconstrictor effect of ET-1, these findings may partially explain the previously observed salutary effect of estrogen in improving intestinal perfusion following T-H in males.
authors.affiliation: Center for Surgical Research and Department of Surgery, University of Alabama at Birmingham, 1670 Univ. Boulevard, Volker Hall, Rm. G094, Birmingham, Alabama 35294-0019, USA.
authors.forename: Zheng F
authors.initials: ZF
authors.lastname: Ba
authors.forename: Tomoharu
authors.initials: T
authors.lastname: Shimizu
authors.forename: Laszlo
authors.initials: L
authors.lastname: Szalay
authors.forename: Kirby I
authors.initials: KI
authors.lastname: Bland
authors.forename: Irshad H
authors.initials: IH
authors.lastname: Chaudry
mesh_terms: D000818:Animals; D065128:Endothelin Receptor Antagonists; D019332:Endothelin-1 / Q000502:physiology*; D004958:Estradiol / Q000494:pharmacology; D005260:Female; D015870:Gene Expression / Q000187:drug effects; D006470:Hemorrhage / Q000503:physiopathology*; D007421:Intestine, Small / Q000098:blood supply*; D008297:Male; D010456:Peptides, Cyclic / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D012039:Regional Blood Flow; D012737:Sex Factors; D012771:Shock, Hemorrhagic / Q000503:physiopathology
chemical_list: D065128:Endothelin Receptor Antagonists; D019332:Endothelin-1; D010456:Peptides, Cyclic; D004958:Estradiol; C072247:cyclo(Trp-Asp-Pro-Val-Leu)