Effect of alloxan on the mouse pancreas during and after recovery from diabetes

Temporary diabetes was produced in mice by the intravenous injection of alloxan, 75 mg. per kilogram of body weight. The beta cells were degranulated within 6 hrs., but changes in microcirculation did not occur until 24 hrs., and did not appear to play arole in initiating damage to the beta cells. The total number of islets was decreased markedly within one week, but cellular proliferation of ducts and islets began as early as two weeks as indicated by in vivo study and radioautography. Improvement in the diabetic state, manifested by lowered blood glucose, coincided with restoration of a number of the islets. Although the total number of islets was not restored completely, the blood glucose values returned to normal, indicating that the new islets were functioning adequately. Replacement of the insular cells occurred solely by budding of new islets from the ducts,and no evidence of acino-insular transformation, or transformation of centro-acinar cellsinto beta cells, was found.

Hyperketonemia induced in man by medium-chain triglyceride

The effect of a medium chain triglyceride (MCT) preparation on blood ketones was determined in fourteen normal subjects and six patients with diabetes mellitus of the maturity-onset type. Ingestion of 100 gm. of the MCT (containing 86 per cent C8 and 14 per cent C10 fatty acids) was followed by a small but statistically significant rise in blood ketones in each of the groups. The rise in ketones was slightly but significantly higher in the diabetic patients than in the normal subjects. In all subjects, ketone rises were negligible after ingestion of 100 gm. of corn oil.

The ketogenic effect of MCT may result in part from its rapid absorption from the gut, with a high proportion of the component fatty acids traveling in the portal vein directly to the liver in the free acid form. In the liver, these fatty acids appear to be rapidly degraded and converted in part to ketones. The predictable mild hyperketonemia induced by MCT makes this glyceride a useful tool in the study of ketogenesis.