Abstract
In the light of a recent study conducted in normal rats, the present investigations were aimed at exploring the immediate and long-term effects of an olive oil-enriched diet (OO diet) on GLP-1 release and intestinal content, plasma insulin concentration, glucose tolerance and pancreatic insulin content in adult rats that had been injected with streptozotocin during the neonatal period (STZ rats). The OO diet, when compared to a standard diet, increased the immediate GLP-1 response in meal-trained rats, but decreased GLP-1 content in the intestinal tract after 50 days. Over 50 days, the body weight gain was lower in the rats fed the OO diet compared to standard diet. In the former, however, no improvement of glucose tolerance or insulin response during an oral glucose tolerance test was observed. Thus, a paradoxical lowering of the insulinogenic index, i. e. the paired ratio between plasma insulin and glucose concentration, was recorded during the oral glucose tolerance test in rats fed either standard or OO diet. Moreover, the insulin content of the pancreas was equally low in the STZ rats fed either standard or OO diet. These findings will be discussed in the framework of possible differences in the pathophysiology of B-cell dysfunction in most patients with type-2 diabetes and the present animal model of non-insulin-dependent diabetes.
Key words
Insulin secretion - streptozotocin-induced diabetic rats - incretin hormone - monounsaturated fatty acids
References
Glucose determination with glucose oxidase and peroxidase. In: Bergmeyer HU (ed) Methods of Enzymatic Analysis. New York; Academic Press 1974: 1205-1215
Physiology of insulin secretion and its alteration in diabetes: the concept of glucotoxicity. In: Adreani D, Gueriguian JL, Striker GE (eds) Diabetic complications: epidemiology and phatogenic mechanisms. New York; Raven Press 1991: 73-92
malaisse@ulb.ac.be
