Ghrelin regulates nightly melatonin secretion from sheep pineal gland in a TPH1- independent manner: An in vitro study

• Autorzy: Kirsz K. , Szczesna M. , Zieba D.A.
• Języki publikacji: EN

Abstrakty

EN

INTRODUCTION: Several studies suggest that ghrelin (GHRL) has neurobiological effects that extend beyond the control of food intake. Our previous results confirmed that GHRL modulates the secretory activity of the pineal gland (PG) through nocturnal melatonin (MEL) secretion in sheep, which are seasonally reproductive animals. AIM(S): We investigated the effects of GHRL and seasons on the tryptophan 5-hydroxylase 1 (TPH1) expression in sheep PG. TPH1 is the rate-limiting enzyme in the biosynthesis of serotonin (MEL precursor). METHOD(S): Glands were collected after sunset from 8 ewes during long-day season (LD; May) and from 8 ewes during short-day season (SD; November). The PG were transected into strips (n=72), with each equilibrated in 1.0 ml of DMEM for 60 min, followed by a 4-hr incubation in a gas-liquid interface in medium alone (control) or in medium containing GHRL (10 ng/ml). After each hr of incubation, selected explants were frozen in liquid nitrogen and stored at −80°C for Real‑time PCR and ELISA. Sixty minutes (light intensity: 400 lux). During following 9 experimental days blue part of the spectrum was blocked by yellow filter (cut off at 525 nm). Locomotor activity, core body temperature and their circadian parameters were compared between light conditions. RESULTS: After blue light blockage amplitude and robustness of the locomotor activity rhythm decreased. A significant reduction in the mean level of activity was observed in the dark phase. Moreover, the mesor of the rhythm of core body temperature decreased, core body temperature was reduced both in the light and the dark phase. CONCLUSIONS: Blue light deprivation results in disturbances in circadian rhythmicity in non-genetically modified rats with fully functional retina. Observed changes resemble those found in depressed patients, suggesting that not only light intensity but also its spectral composition matters. FINANCIAL SUPPORT: Supported by 2013/08/W/ NZ3/00700.

• Wydawca: -
• Czasopismo: Acta Neurobiologiae Experimentalis
• Rocznik: 2017
• Tom: 77
• Numer: Suppl.1
• Opis fizyczny: p.91

Twórcy

autor

Kirsz K.

• Agricultural University of Cracow, Department of Animal Biotechnology, Laboratory of Biotechnology and Genomics, Cracow, Poland

autor

Szczesna M.

• Agricultural University of Cracow, Department of Animal Biotechnology, Laboratory of Biotechnology and Genomics, Cracow, Poland

autor

Zieba D.A.

• Agricultural University of Cracow, Department of Animal Biotechnology, Laboratory of Biotechnology and Genomics, Cracow, Poland