Does alcohol promote reactive hypoglycemia in the rat?

Alcohol induces a reactive hypoglycemia in man, but divergent results have been reported, in man and rats, on the effects of ethanol plus a carbohydrate load. The interactions between ethanol and glucose metabolism are complex. In the present study isocaloric solutions of glucose alone (A) or glucose plus alcohol (B) were administered in rats at the beginning of nighttime. Their effects were compared on blood glucose (BG) levels. Since rats don't drink alcohol spontaneously, glucose was given by mouth and alcohol through an intragastric catheter (IG); in the case of glucose alone half the load was ingested by mouth, and half IG. After administration, BG level was continuously determined in freely moving rats. It was shown that the latency to eat after the ingestion of glucose plus alcohol was significantly shorter and the size of the meal smaller. The postabsorptive hyperglycemia was significantly decreased in B as compared to A. The following hypoglycemia was more severe in B and it appeared earlier. In addition, a stress was applied after both A and B. It is well known that stress are potent stimuli of the sympathetic nervous system which inhibits insulin secretion. In both situations (A and B) with stress, the small preabsorptive hypoglycemia which appeared 4 min after the ingestion was suppressed. The hyperglycemia was higher in situation A with, than without, stress. The subsequent hypoglycemia was significantly lower. After stress in B, there was no difference in the peak of hyperglycemia but it appeared later. So, in rat the ingestion of alcohol together with an oral glucose load could trigger a reactive hypoglycemia. Stress greatly enhanced the phenomenon.