The effects of two neuroleptics (pipotiazine and fluphenazine) and five long-acting neuroleptics (pipotiazine undecylenate and palmitate, fluphenazine enanthate and decanoate, fluopentixol decanoate) are tested in the rat, during an observation period of 20 to 40 days following only one injection of compound. The compounds administered at three different and non toxic doses, are showing effects, the intensity and duration of which are different according to the dose and the compound: diestrus of pseudo-gestation or more than 15 days, hypertrophy of mammary gland, decreasing of the uterine weight. Some long-acting neuroleptics are active during more than forty days.