[Observation on the protective effect of preventive acupuncture and moxibustion on uterus in ovariectomized rats]

To observe the effect of preventive acupuncture and moxibustion of "Guanyuan" (CV 4) on uterus in ovariectomized (OVX) rats.

A total of 80 female SD rats were randomly divided into 5 groups: normal control, sham-operation (sham), model, preventive acupuncture (PA) and preventive moxibustion (PM) groups, with 16 cases in each. PA (with the needle retained for 20 min after insertion) and PM (one moxa-cone/rat) were applied to "Guanyuan" (CV 4) separately before ovariectomy, two times a week, 4 weeks altogether. Then, ovariectomy was performed on rats of model, PA and PM groups. Uterus tissue was taken under anesthesia for homogenate (10 rats/group) or sectioning (5-6 microm, 6 rats/group). Uterus estradiol (E2), progestone (P) were detected with radioimmunoassay; superoxide dismutase (SOD), nitric oxide synthase (NOS), and malondialdehyde (MDA) were assayed with immunoturdidimetry. Partial uterus slices were stained with H & E method for observing morphological changes, or stained with immunohistochemical method or with in situ hybridization method for displaying estrogen receptor (ER)-alpha and ER-alpha mRNA expression separately.

After ovariectomy, the rat's uterus presented obvious squamous metaplasia, hyperplasy, and thickening of the endomembrane, decrease in glands and blood vessels and increase in fibrous connective tissue, etc; while the situation was evidently better in PA and PM groups. In comparison with normal control group, E2, P contents and SOD, NOS activities of uterus tissue in model group decreased significantly (P < 0.01), while MDA in model group increased evidently (P < 0.01). Compared with model group, uterus P content in PA and PM groups increased obviously (P < 0.05), while uterus MDA decreased apparently (P < 0.01). Compared with normal control group, the expression of ER-alpha and ER-alpha mRNA in model group was downregulated markedly (P < 0.01); after PA and PM, both ER-alpha and ER-alpha mRNA expression increased obviously (P < 0.01). No significant differences were found between PA and PM groups in the above mentioned 7 indexes (P > 0.05).

Preventive acupuncture and moxibustion of CV4 can postpone the structural degeneration of uterus in OVX rats, which may be related to their effects in modulating the secretion of uterus E2 and P, upregulating the expression of ER-a and ER-alpha mRNA, and improving the anti-oxidative ability.