Objective: To observe the effects of rhubarb total anthraquinone on function and structure of hypothalamus

pituitary and its reversibility in female rats. Method: Forty female SD rats were selected

in which 10 rats were randomly selected as normal control group

and the remaining 30 rats were administered orally with 73 mg·kg-1 rhubarb total anthraquinone for 60 days. At 24 h

30 d and 60 d after the last administration

1/3 rats were put to death. ELISA was used to detect the gonadotropin-releasing hormone (GnRH)

luteinizing hormone (LH) and follicle-stimulating (FSH) levels in serum. Their estrous cycle was recorded. The pituitary was collected and weighed to calculate the index of pituitary. The morphological changes in hypothalamus and pituitary were observed by HE staining. Result: The LH and FSH levels of the model group at 60 d after administration and 30 d after drug discontinuance were higher than that in the normal control group

and GnRH level was lower than that in normal control group (P<0.05). The LH and FSH level of the model group at 60 d after drug discontinuance were lower than that at 60 d after administration

GnRH level was higher than that at 60 d after administration (P<0.05). The rate of the estrous cycle disordered and the number of diestrus days of the model at 30 d and 60 d after administration were higher than that in normal control group (P<0.05). The rate of the estrous cycle disordered and the number of diestrus days of the model group at 60 d after administration were higher than that at 30 d after administration (P<0.05). The rate of disordered estrous cycle of the model group at 30 d after drug discontinuance was higher than that in normal control group (P<0.05). The indexes of pituitary of the model group at 60 d after administration was higher than normal control group (P<0.05); and that at 30 d and 60 d after drug discontinuance was lower than at 60 d after administration (P<0.05). Pathological examination showed that the hypothalamus neurons of the model group at 60 d after administration reduced

red neurons

ghost cells and chromatin side pole appeared; pituitary cells decreased and became irregular

blood sinus was expanded

adaptability of eosinophilic cell was proliferated. The hypothalamus neurons of the model group at 30 d after drug discontinuance increased

red neurons decreased

ghost cells and chromatin side pole reduced; pituitary cells increased

blood sinus expansion was reduced

adaptability of eosinophilic cell hyperplasia was reduced. Pathological changes of the hypothalamus and pituitary were further recovered in the model group at 60 d after drug discontinuance. Conclusion: Estrogen level

estrous cycle and structure of hypothalamus and pituitary in female rats were affected by 60 d oral administration with rhubarb total anthraquinone

which however is reversible at 60 d after drug discontinuance.