Glucose metabolism in isolated uteri from restricted-diet ovariectomised and non-ovariectomised rats: The influence of dopaminergic blockers

The effects of restricted diet (50% of the normal intake during 25 days) on the metabolism of U¹⁴C-glucose and tissue glycogen, were explored in uterine horn strips isolated from intact and ovariectomised rats. In underfed intact rats, the formation of ¹⁴Co₂ was significantly lower than in their controls, while in castrated rats it remained unchanged. Haloperidol, 0.25 mg and sulpiride 2 mg kg^-1 b.w., injected s.c. 15 h (but not 2 h) before killing, only affected castrated rats subjected to dietary restriction, diminishing ¹⁴CO₂ production. Bromocriptine 7.6 mg kg^-1 injection 1 h before haloperidol, blocked its effect. The addition of haloperidol to the KRB medium had no effect on glucose metabolism. The post-incubation levels of glycogen in uteri from intact normal-fed animals diminished significantly in comparison to 0 time levels values. The glycogen of the uteri from rats subjected to a dietary restriction did not decline. On the contrary, it diminished in ovariectomised rats after incubation, no matter what was the diet. Haloperidol and sulpiride hindered glycogenolysis in castrated rats receiving a restricted diet. We conclude that in uteri of sprayed rats subjected to dietary restriction there was a dopaminergic mechanism which led to a glucose metabolism increase.