Estradiol antagonistic effects of winter cherry extract on pituitary and hypothalamic GOPD activities

ABSTRACT

Intraperitoneal administration of an aqueous extract of winter cherry fruits [Physalis alkekengi] to adult cycling female rats diminished pituitary glucose 6-P dehydrogenase [G6PD] activity by 35% and that of the basomedial hypothalamus [BMH] by 23%. Daily doses of 1.88, 3.75, 7.5, and 15 micro g beta-estradiol administered to such animals for a period of 6-9 days increased pituitary G6PD activity by 16,30,60, and 94% and that of BMH by 14,19,30, and 52%, respectively. Combined administration of a given dose of the aqueous extract along with the above doses of beta-estradiol for 8-9 days reduced G6PD inhibitory effect of the aqueous extract on both the pituitary and BMH. In this manner the pituitary enzyme was inhibited by 14% [1.88 micro g beta-estradiol], 7% [3.75 micro g estradiol] and activated by 37% [7.5 micro g estradiol] and 62% [15 micro g estradiol]. Corresponding values for the hypothalamic enzyme were inhibitions of 21% [1.88 micro g estradiol], 18% [3.75 micro g estradiol], 7% [7.5 micro g estradiol] and activation of 2% [15 micro g estradiol]. The estrogen antagonistic effect of this aqueous extract on the brain is discussed in terms of its possible action on the inhibition of the hypothalamic gonadotropin releasing hormone and the pituitary luteinizing hormone release, thus affecting ovulation and pregnancy