Interactions of insulin with bovine endothelium.

Bovine endothelial cells have been isolated from pulmonary and systemic vessels and grown in culture as primary, passaged and passaged cloned-strains. The cultures were shown to be endothelial in nature on the basis of several endothelial-specific and endothelial-associated traits. Endothelial cells from all sources had specific receptors for insulin in primary culture and after serial passage. Endothelial cells derived from pulmonary arteries and aortas bound 2.5 times more insulin than cells derived from the pulmonary vein. Each endothelial cell type maintained a specific complement of receptors through at least 25 passages in vitro. Coupled with previous findings of insulin receptors on endothelial cells from human umbilical vessels, these data suggest that insulin receptors may be an intrinsic component of all vascular endothelium.

Distribution of 9-H 3 -prostaglandin F 2 in pregnant and non-pregnant subjects.

PIP: This study investigates the distribution of 9-H3-prostaglandin F2a injected intravenously into 3 pregnant (16 to 20 weeks) and 2 nonpregnant women to determine whether any difference in its distribution could be detected between pregnant and nonpregnant subjects. Anesthesia was given to the patients and labelled prostaglandin in 2 ml. of saline injected into an antecubital vein except in 1 where it was injected into a jugular vein. After the injection, blood samples were obtained at regular intervals. Maternal and fetal tissue samples and urine specimens were obtained from the subjects. Within 30 minutes of injection, more than 95% of radioactivity had disappeared from the circulation, with the fall being slightly more rapid in pregnant subjects. In maternal tissue samples, very variable quantities of radioactivity were found in both subcutaneous fat and rectus muscle, while a consistently high level of radioactivity was found in the fetal liver. In other tissues, the radioactive levels were similar to those found in maternal tissues. In 4 patients, nearly all the radioactivity appeared in the urine within 24 hours; in the remaining patient, only 50% of the radioactivity was detected in the urine during the same period. The study shows no difference in the distribution or elimination of the radioactive prostaglandin in pregnant and nonpregnant women. Excretion of radioactivity was extremely rapid and virtually complete within 24 hours, confirming the results of Granstrom and Samuelsson. The high levels of radioactivity found in the fetal liver, rather than in the fetal lungs, may be a reflection of a selective uptake of prostaglandin entering the liver directly via the umbilical vein and ductus venosus.^ieng