EFFECTS OF 7-NITROINDAZOLE, A NEURONAL NITRIC-OXIDE SYNTHASE (NNOS) INHIBITOR, ON LOCOMOTOR-ACTIVITY AND CONTEXTUAL FEAR CONDITIONING IN RATS

The effect of 7-nitroindazole (7-NI), a selective neuronal nitric oxid e synthase (nNOS) inhibitor, on contextual fear conditioning in rats w as examined. Systemic administration of 7-NI did not affect the acquis ition of contextual fear (measured as freezing), but it did reduce loc omotor activity and cause a corresponding increase in the expression o f contextual freezing. It is concluded that nNOS activity is not requi red for either the acquisition or expression of contextual fear condit ioning. (C) 1998 Elsevier Science B.V. All rights reserved.