ABSTRACT
AIM: To observe the effect of altitude hypoxia on glutamate, aspartate and nitric oxide synthase (NOS) in the rat hypothalamus. METHODS: Using altitude hypoxia model, amino acid analysis system and the NADPH-d histochemistry, we determined the content of glutamate, aspartate and the number of NADPH-d neurons in the rat hypothalamus. RESULTS: After altitude hypoxia, the contents of glutamate, aspartate in the hypothalamus of rats were increased significantly, densely and deeply stained NADPH-d neurons were seen in hypothalamic paraventricular nucleus (PVN)and supraoptic nucleus(SON). If rat were pretreated with the NMDA receptor blockers Ketamine (ip,40 mg/Kg)or AP-V(i.c.v, 10 ?g) , the number of NADPH-d neurons in the rat hypothalamic PVN and SON was markedly less than that in corresponding altitude hypoxia group. CONCLUSION: NMDA receptor may take part in the expression of hypothalamic NOS induced by altitude hypoxia.