Effects Of Estrogen On NOS Positive-Neurons In Hippocampal Formation Of Female Rat

Effects Of Estrogen On NOS Positive-Neurons In Hippocampal Formation Of Female RatIn the present study ,we adopted the SABC immunohistochemical technique to observe the changes of morphology and distribution of NOS positive-neurons on hippocampus of three groups Wistar female rats (the reference ,ovariectomized and ovariectomized+estrogen group),which were analyzed with computer graphic analysis system. The study results show: (1) there are comprehensive NOS-positive staining cell groups in all regions of hippocampal formation. Pyramidal cell and oval cell are the two main cells in the three groups, but in CA1,cell dendrite is shorter in OVX group than in reference group. The effects can be reversed by estrogen given for 1 month. (2).The distribution of the neuron containing NOS in the hippocampal formation shows an obvious regional difference in the three groups .OVX in rats caused a decline in both number and area density of positive neurons in hippocampus CA1,CA3,CA4,S and dentate gyrus ,while the number and density of positive neurous in CA2 region have no remarkable changes.The effects can be reversed by estrogen given for 1 month. So it suggests that estrogen can stimulate the compose of nitric oxide, and estrogen may influence the learning and memory by affecting the expression of NOS in hippocampus .