HORMONAL ASPECTS OF KETOSIS*

Response to starvation before and after a jejuno-ileal bypass operation for morbid obesity

A greater metabolic response developed during a seven day starvation in two morbidly obese patients three months after a 90 per cent jejuno-ileal bypass operation when compared with a similar fast before operation. There was a greater degree of ketosis, a decreased urinary urea excretion and an earlier utilization of ketone bodies. These changes suggest a metabolic adaptation of the body to the semistarvation state caused by the operation with a more rapid utilization of adipose tissue as a fuel and a sparing of lean body mass.

Relationship of insulin concentration to blood metabolites in the dairy cow

Jugular blood samples were taken at regular intervals from 31 ketosis-prone cows from 2 wk prepartum to 7 wk postpartum. Eleven cows exhibited elevated blood ketones and depressed blood glucose indicative of subclinical ketosis. There were no significant differences between means of normal and subclinically-ketotic cows in serum insulin or blood metabolites prior to calving. However, in early lactation, those cows which developed ketosis showed depressed serum insulin, blood glucose, and plasma triglycerides with elevated ketones, acetate in blood, and free fatty acids and cholesterol in plasma. Milk production was also lower in ketotic cows. Correlations within cow between serum insulin and glucose, total ketones, acetate of blood and free fatty acids, triglycerides, and cholesterol in plasma were .014,--.307, .080,--.421, .413, and -.002 for normal cows and .348, -.425, -.324, -.317, .298, and -.131 for subclinically-ketotic cows. It is suggested that low insulin during ketosis is a reflection of depressed blood glucose and, consequently, adipose lipolysis and hepatic ketogenesis are accentuated while acetate utilization and hepatic triglyceride release are depressed.

Hepatic lipid metabolism in experimental diabetes: III. Synthesis and utilization of triglycerides

Livers removed from normal rats, from alloxan diabetic rats maintained on insulin for two weeks (ADI+), and from insulin-treated diabetic rats from which insulin had been withdrawn two days before use (AD) were perfused in vitro with 120 mg (468 mumoles) palmitic acid-1-C(14). Under these conditions, output of TG (triglyceride) was depressed in livers from ADI+ rats and was negligible with livers from AD animals. The total incorporation of C(14) into perfusate TG paralleled the chemical measurments of TG output. The concentration of hepatic TG increased during perfusion of livers from normal or ADI+ rats but decreased during perfusion of livers from AD animals.A load of 120 mg of palmitic acid/3 hr was inadequate to maintain net accumulation of TG in livers from AD rats; furthermore it is implicit in this observation that the total load of NEFA (nonesterified fatty acid) perfusing livers from AD rats must be increased considerably to obtain a fatty liver. The total incorporation of C(14) into hepatic TG and the specific activity of hepatic TG were depressed during perfusion of livers from AD rats. The production of ketone bodies by livers from AD animals was about five times the normal rates; the output of ketone bodies did not differ from results of other experiments (1) in which the load of palmitic acid added to the medium was varied from 0-80 mg. These observations were discussed with reference to mechanisms for ketogenesis and fatty liver in alloxan diabetes.