Good versus moderate regulation of alloxan-induced diabetes in arteriosclerotic and nonarteriosclerotic rats.

Nonarteriosclerotic (virgin) and arteriosclerotic (breeder) rats were made diabetic with alloxan. Animals were treated with constantly adjusted doses of insulin, occasionally adjusted doses, or no treatment. The obese breeder rats lost weight; the lean virgin rats gained weight. All of the animals were autopsied 5 months post-alloxan. Blood pressure increased in virgin rats; the pre-existent mildly elevated blood pressure of arteriosclerotic breeder rats decreased. Glucosuria was effectively reduced in animals accorded good control; blood glucose was not effectively controlled. Circulating nonesterified fatty acids and triglycerides were more effectively normalised by insulin therapy. The diabetes was accompanied by adrenal hypertrophy, thymus gland involution, and increased circulating corticosterone. Virgin rats (68%) developed arterial disease when made alloxan-diabetic; treatment with insulin completely prevented arterial disease. Breeder rats with pre-existent arteriosclerosis showing worsening of their cardiovascular disease; when made severely diabetic those provided with good control of their diabetes were protected against exacerbation of their vascular disease.