EFFECTS OF PENITREM-A ON RATS PERFORMANCES IN PASSIVE-AVOIDANCE AND MORRIS WATER MAZE TESTS

Intraperitoneal administration of the mycotoxin penitrem A 30 min befo re a training session in passive avoidance task, impaired performance of rats subjected to a test-session 24 h after. This effect was not an tagonised by pretraining administration of physostigmine or bicucullin e. Administration of penitrem A 20 min before a training session or 30 min before a test-session did not impair performance. In the Morris w ater maze, doses of penitrem A that induces slight to moderate tremors , but not a lower dose, disrupted place learning. These results sugges t that penitrem A disrupts the processes that take place at the time o f acquisition, but not those just after acquisition, and does not alte r the restitution of information. This effect would not be related to a decrease of cholinergic neurotransmission nor to a stimulation of GA BA A receptors. Nevertheless, it could not be totally excluded that th e performance impairments induced by penitrem A would be secondary to a motor disruption.