IMPACT OF MORPHINE DEPENDENCE ON NOS POSITIVE NEURONS IN MICE HIPPOCAMPUS

Objective: To study the impact of morphine dependence on the activity of NOS in subareas of mice hippocampus.Methods: Mice were given (sc) gradually increasing doses of morphine to form morphine dependent model. NADPH-diaphorase with a histochemical method was used to study the distribution areas of NOS positive neurons in CA1, dentate gyrus and CA3 of hippocampus of morphine dependent group, naloxone-precipitated withdrawal group in morphine dependent mice and control group. Results: Compared with control group , the number of positive cells decreased obviously in CA1 and dentate gyrus of both groups in morphine dependent mice, especially the later. Conclusion: The activity of NOS in CA1 and dentate gyrus of morphine dependent and naloxone-precipitated withdrawal groups has decreased, especially the later, which suggests that the synthesis of NO has decreased. Those changes may be some of the reasons causing learning and memory deficits.