Effects of peptidic growth hormone secretagogue receptor (GHS-R) antagonist [D-Lys3] on some of serum hormonal and biochemical parameters in Wistar rat model

Efeitos do antagonista [D-Lys3] do receptor do peptídeo secretagogo do hormônio do crescimento (GHS-R) sobre alguns parâmetros bioquímicos e hormonais séricos em um modelo em ratos Wistar

Objective

: The present study investigated the effects of different dosages of a GHS-R antagonist [D-Lys3] on some serum hormonal (cortisol, T₃ and T₄) and biochemical parameters in a rat.

Materials and methods

: Thirty-six 60-day-old male rats were assigned to four treatments. [D-Lys3]-GHRP-6 solutions were infused via intraperitoneal injections. Blood was collected and analyzed.

Results

: The large dosages of a GHS-R antagonist (200 ng/kg BW) caused increases in cortisol, whereas no significant changes occurred when low dosages were injected. There were no significant changes in T₃ and T₄ following the administration of the GHS-R antagonist, but a considerable increase was observed in blood glucose levels of the groups (G50, G100, and G200 ng/kg BW). There was a significant increase in total protein when the greatest dose was administrated (G200 ng/kg BW). However, total cholesterol, triglycerides, and albumin showed no significant changes.

Conclusions

: Exogenous GHS-R antagonist can cause an increase in glucose and moderate increases in cortisol and total protein, yet it has no significant effect on T₃ and T₄ levels or on the concentrations of serum lipids. The effect of GHS-R antagonist is not completely adverse to the effects of ghrelin. Further molecular studies are necessary to identify the physiological effects of the peptidic GHS-R antagonist. Arq Bras Endocrinol Metab. 2014;58(3):288-91

Ghrelin receptor; GHS-R; GH-releasing; regulatory peptide; peripheral infusion