Objective To explore the possible mechanism of Shugan Jianpi Recipe（ 疏肝健脾方） in the treatment of postpartum hypogalactia of liver depression and spleen deficiency syndrome. Methods A total of 60 Wistar pregnant rats with due date were randomly divided into model group

blank control group

western medicine control group and Shugan Jianpi Recipe low

medium and high dose groups

with 10 rats in each group. Except the blank control group

the rats were established the model of postpartum hypogalactia of liver depression and spleen deficiency syndrome using bromocriptine mesylate + chronic restraint method. After modeling

the western medicine control group was given 3. 15 mg/（ kg·d） of metoclopramide tablet solution

and the Shugan Jianpi Recipe low

medium and high dose groups were intragastrically administered with 1. 109

2. 218

4. 435 g/ml of Shugan Jianpi Recipe solution respectively

5 ml per rat. The model group and the blank control group were intragastrically administered with equal volume of distilled water. Each group was intragastrically administered once in the morning and evening for 7 days.Reverse transcription-polymerase chain reaction（ RT-PCR） was used to detect the expression of tyrosine kinase 2（ JAK2）

signaling and transcriptional activator 5 A（ STAT5A）

prolactin receptor（ PRLR） and β-casein mRNA in breast tissue. The expression of JAK2

STAT5A

PRLR and β-casein protein in breast tissue was detected by Western blot. Results Compared with the blank control group

the levels of JAK2

STAT5A

PRLR and β-casein mRNA and protein in the mammary gland in the model group

the western medicine group and the Shugan Jianpi Recipe low and high dose group were significantly decreased（ P < 0. 05）

while there was no significant difference in the Shugan Jianpi Recipe middle dose group（ P > 0. 05）. Compared with the model group

the levels of JAK2

STAT5A

PRLR and β-casein mRNA and protein in the mammary gland of rats in the western medicine control group and all Shugan Jianpi Recipe groups were increased

and the middle dose group was significantly higher than the other drug groups（ P <0. 05）. Conclusion The mechanism of Shugan Jianpi Recipe in the treatment of postpartum hypogalactia of liver depression and spleen deficiency syndrome may be related to the promotion of prolactin binding to its receptor

activation of JAK2/STAT5A signal transduction pathway

and up-regulation of β-casein gene expression.