The Changes Of Activity Of Nitric Oxide Synthase And Distribution And Structure Of NNOS Positive Neurons In Rabbit Limbic System After Ovariectomy And Estrogen Replacemen Therapy

To study the effect of estradiol benzoate and progesterone on the activity of NOS and distribution and structure of nNOS positive neurons in Rabbit limbic system, female rabbits were spayed as models of women who are in perimenopausal period in this experiment. The comparation of NO solution and the changes of NOS activity and expression of nNOS in rabbit limbic system were observed after estrogen replacement therapy and combined hormone replacement. All this research work will provide a basis for the study of Menopausal Syndrome and nervous system disease, especially the study of the physiology of nervous pathology.The first periment studied the change of nNOS-positive neurons in the sections of the hippocampus and in PVN,LHA,SON of hypothalamus and frontal lobe under light microscope following ovariectomy and estrogen replenish. Results: There were comprehensive nNOS-positive staining cell groups in all regions of hippocampus and hypothalamus and frontal lobe. After ovariectomy, the changes of nNOS positive neurons in subregion were not equal: the obvious to die down of the nNOS expression in frontal lobe and in all regions of hippocampus but CA2, while the obvious to build up of the nNOS expression in the each nerve pit of hypothalamus, namely a increasing amount and a deeper dyeing. There was no significant difference between estradiol-replacement therapy and the control group. The obvious to build up of the nNOS expression in frontal lobe and in all regions of hippocampus but CA2, and the obvious to weaken of the nNOS expression in each nerve pit of hypothalamus, namely a decreasing amount and a lighter dyeing compared with the ovariectomy group.The second experiment studied NO levels and the activity of NOS in rabbit limbic system after ovariectomy and estrogen replacemen therapy and combined hormone replacement by the method of nitric acid reductase and metabolic chemistral method. Results: there was a significant decrease of NO levels and the activity of NOS compared with control group after ovariectomy. NO level and the activity of NOS increased after using estrogen only and group of combined hormone replacement. NO level and the activity of NOS after using estrogen only were hingher than the group of combined hormone replacement,but there was no significant difference.