Objective: To study the effect of Kuntai capsule on expressions of B-cell lymphoma/leukemia 2 (Bcl-2) and Bcl-2 associated X protein (Bax) protein in rats with decreasing ovaries reserve (DOR) induced by 4-vinylcyclohexene diepoxide (VCD). Method: The model of DOR of Sprague-Dawley female rats was established through intraperitoneal injection with 80 mg·kg-1 of VCD for continuously 15 days. Since the 1st day of modeling

the SD rats were orally administered with drugs for 45 days. They were divided into the normal group

the model control group

high

middle and low-dose Kuntai capsule groups (1.89

0.63

0.21 g·kg-1)

and Estradio Valerate group (0.13 mg·kg-1). follicle-stimulating (FSH)

lactogenic hormone (LH)

estradiol (E2) were detected by ELISA method. HE staining was used to observed histopathologic changes in ovary and uterus. Expression levels of Bcl-2 and Bax protein in rats ovarian were detected by Western blot method. Result: Compared to the normal group

FSH

LH of the model control group increased strikingly

and E2 decreased (P<0.05). Ovarian and uterus were shrunk remarkably. The numbers of primordial follicles and primary follicles reduced obviously. The endometrium became thin. The expression of Bcl-2 protein of model group decreased obviously

whereas the expression of Bax protein of model group increased (P<0.05)

Bcl-2/Bax ratio of model group decreased sharply (P<0.01). Compared with the model group

FSH of high

middle and low-dose Kuntai capsule group decreased

while E2 increased (P<0.05). FSH

LH of Estradio Valerate group decreased

while E2 increased(P<0.05). After intragastric administration

the volume of ovaries and uteruses of Kuntai capsule group and Estradio Valerate group increased

and the numbers of primordial follicles and primary follicles increased. The endometrium became thick. The order of alleviation degree from low to high was low

middle and high-dose Kuntai capsule groups and Estradio Valerate group. The expression of Bcl-2 protein of high

middle and low-dose Kuntai capsule groups and Estradio Valerate group significantly increased (P < 0.05

P < 0.01); The expression of Bax protein of high

middle and low-dose Kuntai capsule groups and Estradio Valerate group significantly decreased (P<0.05). Bcl-2/Bax ratio of high

middle and low-dose Kuntai capsule groups and Estradio Valerate group increased (P < 0.05

P < 0.01). Conclusion: Kuntai capsule can improve the function of ovaries by up-regulating the expression of Bcl-2 protein and down-regulating the expression of Bax protein in ovarian.