The comparative usefulness of crystalline human, porcine, dealaninated porcine and bovine insulin in the treatment of insulin resistance was studied.
A series of normals, insulin-sensitive diabetics, and insulin-resistant diabetics received various types of insulin in acute intravenous tolerance tests. The insulin-resistant patients were far less responsive to all forms of insulin in these tests than were the normals and insulin-sensitive diabetic patients. No positive correlation was found between responsiveness to a particular type of insulin in an acute tolerance test and responsiveness during a prolonged clinical trial.
Seven patients with insulin resistance received clinical trials with at least one insulin other than bovine. Three of these patients were found to be more sensitive to either human, porcine or dealaninated porcine than to bovine insulin. Insulin binding capacities of sera from the responsive patients were somewhat higher than the binding capacities of the nonresponders. The insulin binding capacities of sera from the responsive patients were just as high or higher for the insulin to which the patient responded as they were for bovine insulin. Serum from the responsive patients in general antagonized added porcine, dealaninated porcine and bovine insulin to the same degree in vitro. Adipose tissue from the responders was no more sensitive to human or porcine than to bovine insulin in vitro.
The increased sensitivity of these patients to insulin from a nonbovine source may be due to a difference in kinetics of the antigen-antibody reaction in vivo which is not demonstrable in vitro.
Patients with obesity and insulin resistance responded to a reducing diet. Three of four such patients placed on 600 to 900 calorie diets lost their need for insulin over a fourto six-week period.