RESUMO
Objective:To investigate the regulatory mechanism of Bushen Zhuyun prescription（BSZYP） on endoplasmic reticulum stress （ERS） in rats with luteal phase defect （LPD） induced by mifepristone. Method:Fifty SD rats were randomly divided into a blank group， a model group， a positive control group （dydrogesterone，0.02 g·kg<sup>-1</sup>）， and low-（0.08 g·kg<sup>-1</sup>）and high-dose （0.24 g·kg<sup>-1</sup>） BSZYP groups. Western blot and Real-time fluorescence-based quantitative polymerase chain reaction （Real-time PCR） were used to detect the mRNA and protein expression levels of immunoglobulin binding protein （BIP）， protein kinase R-like endoplasmic reticulum kinase （PERK）， inositol-requiring enzyme 1 （IRE-1）， activating transcription factor 6 （ATF6）， and C/EBP homologous protein （CHOP）. The enzyme-linked immunosorbent assay （ELISA） was used to detect the serum progesterone （P） and estradiol （E<sub>2</sub>） levels. Result:Compared with the blank group， the model group showed the elevated protein expression of BIP， PERK， and CHOP （<italic>P</italic><0.01） and the dwindled mRNA expression of PERK and CHOP （<italic>P</italic><0.05）， while no significant difference was observed in the protein expression of IRE-1 and ATF6， mRNA expression of IRE-1， BIP， and ATF6， and serum E<sub>2</sub> and P levels. Compared with the model group， the positive control group displayed diminished protein expression of CHOP （<italic>P</italic><0.01）， while no significant difference was observed in the protein expression of PERK， IRE-1， BIP， and ATF6， mRNA expression of PERK， IRE-1， BIP， ATF6， and CHOP， and serum levels of E<sub>2</sub> and P. The protein expression of CHOP decreased （<italic>P</italic><0.01） and the mRNA expression of CHOP increased （<italic>P</italic><0.05） in the low-dose BSZYP group， while no significant difference was observed in the mRNA and protein expression of PERK， IRE-1， BIP， and ATF6， and serum E<sub>2</sub> and P levels. In the high-dose BSZYP group， the protein expression of PERK， BIP， and CHOP was down-regulated （<italic>P</italic><0.01）， and the mRNA expression of CHOP was up-regulated （<italic>P</italic><0.01）， while no significant difference was observed in the protein expression of IRE-1 and ATF6， mRNA expression of PERK， IRE-1， BIP， and ATF6， and serum E<sub>2</sub> and P levels. Conclusion:BSZYP can treat LPD by relieving ERS.
