Effect of Glucoprivation Induced by 2-deoxy-D-Glucose on Serum Gonadotropin Levels, Pituitary Response to GnRH and Progesterone-Induced Release of Luteinizing Hormone in Rats

Abstract

Intact (experiment 1) or castrated (experiment 2) male rats were either fed or fasted for 24 hours. Half of each group received 75 mg 2-deoxy-D-glucose/100 gm body weight, intraperitoneally. Assays of sera from blood samples obtained from intact rats 4 hr after the injection revealed that 2-deoxy-D-glucose suppressed serum testosterone levels (P < 0.05) while 2-deoxy-D-glucose plus fasting was most effective in suppressing LH and FSH. In castrates LH was suppressed by 2-deoxy-D-glucose and FSH by fasting (P < 0.01 and P < 0.05). Serum glucose was elevated 3-5 fold by 2-deoxy-D-glucose (P < 0.01). Experiments with female rats revealed that treatment with 2-deoxy-D-glucose had no effect on the rise in serum LH that followed GnRH treatment in ovariectomized, steroid-primed animals. However, progesterone-induced LH release in estrogen-primed ovariectomized rats was blocked by 2-deoxy-D-glucose. Collectively, these results suggest that glucoprivation impairs hypothalamic control of gonadotropin secretion.