Objective: To investigate the effects of Yangyin Yishen particle (YYP) on HPA axis in glucocorticoid (GC)-induced kidney Yin-deficiency rats. Method: Totally 60 Wistar rats were randomly divided into normal group

model group

YYP high-

medium-

low-dose groups (6.48

3.24

1.62 g·kg-1·d-1) and Liuwei Dihuang wan group (0.39 g·kg-1·d-1)

with 10 rats in each group. Except for the normal group

all of rats in other groups were intraperitoneally injected with 50 mg·kg-1·d-1 hydrocortisone for 7 consecutive days to establish setted up the kidney Yin-deficiency rat model by intraperitoneal injection of 50 mg·kg-1·d-1 hydrocortisone for 7 consecutive days. The normal group and the model group rats were gave given distilled water (10 mL·kg-1·d-1) by intragastrically

the YYP high-

medium-

low-dose groups and Liuwei Dihuang wan group were gave given the corresponding drugs by gavage for 7 days. The general situations changes of in general situations

such as rats activity

body hair

tail

food intake

stool and weight

were observed. The bilateran adrenal glands were removaled. The adrenal glands' weight and weight index were measured. The plasma level of corticotropin releasing hormone (CRH)

adre-nocorticotropic hormone (ACTH) and cortiso (CORT) were tested by enzyme-linked immuno sorbent assay(ELISA) method. The CRH mRNA of hypothalamus

the ACTH mRNA of pituitary gland

and the CORT mRNA of adrenal gland were checked detected by reverse transcriptasepolyerase chain reaction(RT-PCR). The adrenal histology of adrenal were was inspected by hematoxyin-eosin(HE) staining. Result: Compared with the normal group

the general condition of the model group were poorer

showing the weight lost significantly (P < 0.01)

the weight of adrenal gland and adrenal gland index decreased remarkably (P < 0.01)

the CRH

ACTH and CORT of plasma reduced (P < 0.01)

the mRNA expressions of CRH

ACTH and CORT were down-regulated (P < 0.01)

with severe adrenal lesions. Compared with the model group

the general situations and weight of adrenal gland

adrenal gland index

CRH

ACTH and CORT of the YYP high-

medium-

low-dose group and Liuwei Dihuang wan group rised (P < 0.05

P < 0.01)

adrenal glands' weight and weight index

the mRNA of CRH

ACTH and CORT were up-regulated (P < 0.01)

and CRH

ACTH and CORT mRNA expressions were up-regulated remarkably

and the lesions degree of adrenal reduced. Conclusion: The Yangyin Yishen particle has the antagonistic effect against the inhibited HPA axis for kidney Yin-deficiency rat induced by GC.