RESUMO
OBJECTIVE: The purpose of this study was to investigate the direct effects of thyrotropin-releasing hormone on isolated human myometrium that was obtained during pregnancy and on human umbilical vasculature in vitro. STUDY DESIGN: Isolated human myometrial strips were dissected from biopsy specimens that were obtained at elective cesarean delivery and suspended for isometric recording under physiologic conditions. The effects of cumulative additions of thyrotropin-releasing hormone (10(-9)-10(-4) mol/L) on oxytocin-induced myometrial contractility were evaluated. The effects of thyrotropin-releasing hormone (10(-9)-10(-4) mol/L) on umbilical vessel (artery and vein) resistance in vitro were investigated with the use of isolated ring preparations. RESULTS: Thyrotropin-releasing hormone exerted a significant concentration-dependent relaxant effect on pregnant human myometrial tissue, which ranged from 3.54% (10(-9) mol/L, P=.935) to a net cumulative total of 21.06% (10(-4) mol/L, P<.001). Thyrotropin-releasing hormone also exerted a concentration-dependent relaxant effect on human umbilical vasculature that ranged from 12.51% (10(-9) mol/L, P=.994) to a net cumulative total of 23.27%+/-4.87% (SEM, 10(-4) mol/L, P<.01) in umbilical artery. For umbilical vein, the relaxant effect ranged from 1.80% (10(-9) mol/L, P=.998) to a net cumulative total of 14.64% (10(-4) mol/L, P<.009). CONCLUSION: Thyrotropin-releasing hormone exerts a significant relaxant effect in human myometrium and in human umbilical vasculature and highlights a potential physiologic role for this neuropeptide in these tissues. These findings have clinical implications for the therapeutic use of thyrotropin-releasing hormone antenatally.
Assuntos
Miométrio/efeitos dos fármacos , Hormônio Liberador de Tireotropina/farmacologia , Cordão Umbilical/irrigação sanguínea , Adulto , Vasos Sanguíneos/efeitos dos fármacos , Relação Dose-Resposta a Droga , Feminino , Humanos , Técnicas In Vitro , Contração Isométrica/efeitos dos fármacos , Concentração Osmolar , Gravidez , Hormônio Liberador de Tireotropina/administração & dosagem , Contração Uterina/efeitos dos fármacos , VasodilataçãoRESUMO
Previous reports suggest that up to 70% of patients undergoing surgery for Crohn's disease of the large bowel do not have gastrointestinal continuity restored and require a permanent ileostomy. In this study the experience with patients requiring surgical treatment of large bowel Crohn's disease is reviewed with particular reference to the management of the rectum. The records of 19 elective and 25 urgent colonic resections performed for large bowel Crohn's disease in 44 patients (16 males, 28 females; mean age 41 years, range 17-76) between 1983 and 1995 were reviewed. Staged proctectomy was performed in 5 of 12 patients who had colectomy for acute colitis and in one patient who had had an elective colectomy. Permanent ileostomy was required in 72% of patients with acute Crohn's colitis and 84% of patients who had elective surgery for large bowel Crohn's. Over 70% of patients having surgical treatment of Crohn's disease of the large bowel required permanent ileostomy. No cases of cancer developed in patients with retained rectal stumps.