Modifications of striatal dopamine levels by steroid contraceptive drugs in mice and rats

Abstract

The effect of steroid contraceptive drugs (SCDs) on the concentration of dopamine (DA) in the striatum was studied in mice and rats. Mestranol was combined with each one of the three progestins, lynestrenol, norethindrone and norethynodrel. Treatments were given daily for 1, 4 or 30 days; animals were sacrificed 1 or 18 h after the last administration. In all groups, with the exception of the animals sacrificed 1 h after an acute treatment, striatal DA was significantly lower than in controls.

PIP: The effects of lynestrenol, norethindrone, or norethynodrel, each in combination with mestranol, on the concentration of dopamine in the striatum of rats and mice were studied. The animals were treated for 1, 4, or 30 days and sacrificed 1 or 18 hours after the last treatment. All treatment groups, with the exception of those treated acutely for 1 day with lynestrenol-mestranol, showed significantly (p less than .01) reduced concentrations of dopamine in the striatum. The physiological significance of this reduction remains to be elucidated.