Oral contraceptives: effects on plasma insulin response to glucose and on the response to insulin and 2-deoxyglucose uptake by peripheral tissue.

Oral contraceptive steroids, norethynodrel and mestranol, were fed to 11-wk-old female Sprague-Dawley rats, in combination and in quantities proportional to those used by women for contraceptive purposes. Three experiments were performed. The first experiment, demonstrated that 10 wk of treatment, impaired the animal's glucose tolerance, but not its insulin response to glucose. The second experiment demonstrated that 6 wk of steroid feeding, decreased the in vivo conversion of blood U-14C-labeled glucose into adipose tissue fatty acids and into diaphragm glycogen, although the effect on the diaphragm was not statistically significant. In the third experiment, it was found that the uptake of 2-deoxyglucose-1-14C by the adipose tissue removed from rats after 6 wk of treatment, was not different from that of control tissue, but the uptake by the hemidiaphragms was slightly lower.