Changes in the content of luteinizing and follicle-stimulating hormones in the gonads of Danio rerio fish under the action of a synthetic analogue of kisspeptin 1

BACKGROUND: Kisspeptin 1 plays a significant role in regulating the activity of the hypothalamic-pituitary-gonadal axis. It is known it interacts directly with gonadotropin-releasing hormone by stimulating its secretion in the hypothalamus and thus affecting downstream sex hormones via gonadotropins, but the exact mechanism of kisspeptin 1 effects on follicle-stimulating and luteinizing hormones is poorly understood. AIM: To investigate the effects of a synthetic kisspeptin 1 analog on follicle-stimulating and luteinizing hormone levels in the gonads of Danio rerio. MATERIALS AND METHODS: The study involved 84 sexually mature Danio rerio females after spawning. The model animals were anesthetized with lidocaine and synthetic analog of kisspeptin 1, 0.9% sodium chloride solution were administered intracerebrally in doses of 2, 8 µg/kg. After 1 or 4 hours, follicle-stimulating and luteinizing hormone’s levels were measured using enzyme immunoassay. RESULTS: A statistically significant increase in follicle-stimulating hormone levels occurs at a dose of 8 µg/kg after 1 and 4 hours and at a dose of 2 µg/kg 4 hours after injection relative to the corresponding control groups. An increase in luteinizing hormone’s production was also recorded at a dose of 8 μg/kg after 1 and 4 hours of exposure compared with the control. Elevated follicle-stimulating and luteinizing hormone’s levels were also recorded at a dose of 8 μg/mg and exposure for 1 hour relative to a dose of 2 μg/kg at the same resting time. Without taking into account the time exposure, the administration of synthetic analog of kisspeptin 1 at a dose of 8 µg/kg leads to an increased level of both hormones, and a dose of 2 µg/kg contributes to an increase in luteinizing hormone’s level. CONCLUSIONS: The obtained results contribute to the study of pharmacological functions of synthetic analog of kisspeptin 1 and in the future can be used for therapeutic purposes in the treatment of diseases of the gonadal system.