Current problems in the measurement of gastrin release. A reproducible measure of physiological gastrin release

The interpretation of gastrin release is confused because of variation in the technique of the radioimmuoassay of gastrin, the lack of a standard stimulus for the release of gastrin and diversity in the method used to express the results. These problems have been analysed (a) by examining the cross-reactivity of three gastrin antisera and using each of the antisera to measure basal gastrin levels in fasting normal subjects, duodenal ulcer and post-vagotomy patients; (b) by determining a satisfactory stimulus for gastrin release in normal subjects; (c) by examining the results to determine the best method of presenting the data. The different a ntisera used were found to give different levels of plasma gastrin in the same sample of plasma. This was not related to the cross reactivity of the antisera. An English breakfast was found to be the most satisfactory stimulus for the release of gastrin. The expression of the results of such a stimulus of gastrin release was affected least by assay variation when the incremental integrated gastrin response was used. It is concluded that the incremental integrated gastrin response to an English breakfast is a satisfactory method for exploring variations in gastrin release.     

Pulmonary venoocclusive disease

The tortoise intestine capability for active transport of sugars has been studied in vitro at 30 degrees C, using labelled sugars. A release of glucose from the glycogen stores of the intestinal wall to the medium took place throughout the incubation period of the sacs. An active transport of 14C-D-glucose against a concentration gradient from the mucosal to the serosal compartment was evident, whereas no such activity could be detected for 14C-D-galactose. The tissue oxygen uptake was 36% higher with glucose than with galactose in the medium.     

The effect of indomethacin on renal function in pentobarbital-anesthetized dogs

The effects of indomethacin, an inhibitor of prostaglandin synthesis, on renal blood flow, glomerular filtration rate, urine flow and excretion of sodium and potassium were studied in the anesthetized dog. Indomethacin, 2.5 mg/kg i.v., decreased renal blood flow but increased aortic pressure and calculated renal vascular resistance. Glomerular filtration rate was not influenced by the synthetase inhibitor. Sodium excretion was decreased and para-aminohippurate extraction was increased after administration of indomethacin. Transient decreases in urine flow and potassium excretion were observed; however, both parameters returned to control value 75 minutes after administration of indomethacin. The early decrease in urine flow rate correlated closely with the decrease in sodium excretion. These data suggest that in the anesthetized dog, endogenous prostaglandins may serve to maintain renal blood flow but not glomerular filtration rate. Under the conditions of the present experiments, sodium excretion and to a lesser extent potassium excretion have been suggested as being dependent on prostaglandin synthesis.     

Obstetric outcome of pregestational diabetic pregnancies

This retrospective study examined the obstetric and neonatal outcome in 23 pregestational diabetic pregnancies. The incidence of congenital malformations and mortality in infants of diabetic mothers was increased compared to the control population. Late booking for antenatal care and poor glycaemia control are probably the reasons for this high incidence. There was also a significantly higher preterm delivery and Caesarean section rate in the pregnancies complicated by pregestational diabetes. The neonatal morbidity was also higher than the controls in terms of jaundice, hypoglycaemia, respiratory distress syndrome and admissions to neonatal intensive care unit. Only with preconception counselling and tight glycaemia control in the periconception period and throughout pregnancy can we expect a drop in the complication rates in pregestational diabetic pregnancies.