Effects of leptin on the release of luteinizing hormone, growth hormone and prolactin from cultured bovine anterior pituitary cells

Abstract

ABSTRACTThe effects of leptin on the release of luteinizing hormone (LH), growth hormone (GH) and prolactin (PRL) were studied in cultured bovine anterior pituitary (AP) cells in vitro. The AP cells were obtained from fully‐fed Japanese Black steers and were incubated for 3 h with 10−13 to 10−7 mol/L of leptin after incubating in Dulbecco's modified Eagle's Medium for 3 days. Leptin significantly increased the concentration of LH in the culture medium by 45 and 44% at doses of 10−8 and 10−7 mol/L, respectively, compared with the controls (P < 0.05). Leptin significantly increased the concentration of GH in the culture medium by 14 and 12% at doses of 10−8 and 10−7 mol/L, respectively (P < 0.05). Leptin also significantly increased the concentration of PRL in the culture medium by 26% compared with the controls at a dose of 10−7 mol/L (P < 0.05). These results show that leptin stimulates the release of LH, GH and PRL by acting directly on bovine AP cells from fully‐fed steers.