Extracorporeal perfusion of the human uterus

Uterine specimens specially prepared for extracorporeal perfusions (arterial and venous stumps available for catheterization) were perfused with oxygenated Krebs-Ringer bicarbonate-glucose buffer for periods of up to 12 hours to investigate the feasibility of obtaining constant flow, stability of biochemical parameters, and adequate distribution of the perfusion fluid. Flow rates of 10 to 30 ml/min per artery could be maintained at pressures ranging from 80 to 120 mm Hg. Arteriovenous gradients of oxygen and carbon dioxide tensions were relatively stable and levels of lactate, lactic dehydrogenase, and creatine kinase released to the medium, indicators of tissue hypoxia or cell lysis, declined after 30 minutes of perfusion, remaining low and stable up to 12 hours. Distribution of methylene blue and radiopaque solutes was practically complete throughout the fundus and upper two thirds of the uterus. A mixture of tritium-labeled estrone sulfate and carbon 14-labeled estrone was injected as a bolus through an arterial catheter during perfusion. Perfusate samples were collected for 30 minutes, and tissue samples were taken at the end of this period. Tritium/carbon 14 ratios in myometrium and perfusate indicated preferential uptake of the unconjugated estrogen. Tritium/carbon 14 ratios were higher in endometrium than in myometrium, which suggests an enhanced permeability of endometrial capillaries to estrone sulfate.