CLOMIPRAMINE MODIFIES FLUCTUATIONS OF FORCED SWIMMING IMMOBILITY IN DIFFERENT PHASES OF THE RAT ESTROUS-CYCLE

Many symptoms that define the premenstrual syndrome (PMS) are present in depressive states, The fact that there are not adequate animal mode ls to study the PMS may explain the lack of knowledge about its etiolo gy, An alternative might be the use of animal models which are useful to study depression, such as the forced swimming test. Eighteen female rats were subjected to the forced swimming test once a week for six c onsecutive weeks, An increase of immobility was observed during diestr us as compared to estrus, On the other hand, some premenstrual symptom s have been suggested to be caused by the influence of gonadal hormone s on the activity of central serotonergic systems, Thus, the effects o f clomipramine were further studied, The drug reduced rat immobility d uring diestrus, so that the differences between the two estrous cycle phases disappeared, We conclude that the use of the forced swimming te st might be a helpful model in the study of PMS.