Possible Interaction: Glucose and Gonadotropin-Releasing Hormone

“Although similar increases in plasma glucose were observed with the two peptides, oral glucose almost abolished the GH response to GHRH (peak, 5.6 +/- 0.9 micrograms/L, P < .01) while only blunting the somatotrope response to hexarelin (peak, 38.4 +/- 7.9 micrograms/L, P < .05).”

“The effect was confirmed with an AMPK antagonist, Compound C. Collectively, these findings demonstrate that glucose can directly regulate GnRH transcription, while implicating the AMPK pathway as an essential mediator of nutritional signaling in a novel GnRH neuronal cell model.”

“Furthermore, glucose as well as food may act as a satiety factor in gonadotropin-releasing hormone pulse generation.”

“ Glucose is considered a key metabolic regulator that fine-tunes pulsatile GnRH release.”

“High serum concentrations of FFA or glucose suppressed the growth hormone (GH) response to GH releasing hormone (GHRH), whereas glucose inhibited and FFA enhanced pituitary LH response to GnRH.”

“Intravenous injection of a lipid emulsion or glucose suppressed the GH and LH response to GH releasing hormone (GHRH) and GnRH, respectively.”

“In the present study, we tested the hypothesis that insulin and/or glucose is a metabolic modulator of GnRH secretion and mediates the effects of nutrition on gonadotrophin secretion.”

“The luteinizing hormone response to gonadotroph-releasing hormone was suppressed (P < 0.03) by glucose and enhanced (P < 0.03) by FFA.”

“For example, glucose and pheromones alter the hypothalamic secretion of GnRH and LH.”

“Both TRH (5μg/ kg iv) and glucose (2 g/kg orally) did not significantly alter baseline GH levels but reduced the GH response to GH‐releasing hormone (GHRH) (2 μg/kg iv), although this effect was more clear‐cut with TRH than with glucose.”