Neuromodulatory effects of progesterone on premotor signs of a 6-hydroxydopamine rat model of Parkinson´s disease.

CASAS S.; GARCÍA S.; CABRERA R.; YUNES R.

Mendoza

Congreso; XXVIII Reunión Científica Anual de la Sociedad de Biología de Cuyo; 2010

Sociedad de Biología de Cuyo

Parkinson’s disease (PD) is the second most common neurodegenerative disorder in humans.Today it is commonly agreed that premotor symptoms precede the motor phase by several years. Our objetives was 1)To study the progesterone (P) effects on two premotor signs: cognitive disorders in an appetitive model of memory and depression like behavior in a forced swimming test. To explore these objetives we tested the animals at week 4 post-lesion. The neurotoxic 6- hydroxydopamine (6-OHDA) infused in left striatum to induce neurodegeneration of the dopamine pathway. The experimental groups were: 1)(SHAM); 2)(Lesion); 3)(Lesion plus P sc (4 mg/kg) 7 days post-lesion). A significant less amount of exploration of the novel object -i.e. memory deficit- was shown in lesioned animals without P treatment. This experimental group, on the other hands, showed a clear depresive like mood when tested in the forced swimming test. If treated with the tryciclic antidepressant imipramine this behavior did not differ from other groups. But the others groups did not have any changes. In brief: 1)we detected a putative memory deficit in an appetitive task and this memory deficit could be more a consequence of a premotor depression-like behavior and not a memory deficit itself. Since P reverted the depression like behavior it is proposed a posible non genomic neuroprotective action mediated by modulatory changes on NT systems.