Effect of tumor necrosis factor-α on progesterone production by granulosa cells in laying hens of different genetic lines

Abstract

In vitro progesterone production by granulosa cells in the presence or absence of human recombinant tumor necrosis factor-alpha (hrTNF-α) was measured at 10, 20, and 30 wk of egg production in White Leghorn hens selected for high (HA)- or low-antibody (LA) response to sheep red blood cell challenge. Isolated granulosa cells from the three largest preovulatory follicles (F1–F3) were incubated with 5 or 250 ng/ml hrTNF-α, and progesterone production was determined by the use of a validated radioimmunoassay. F1, F2, and F3 granulosa cells from HA hens produced more (P ⩽ 0.05) progesterone (140.8, 107.2, and 49.7 ng/ml) than LA hens (109.4, 78.9, and 26.9 ng/ml). The treatment of granulosa cells with hrTNF-α consistently inhibited (P ⩽ 0.05) progesterone secretion by all follicles among HA and LA hens, but not always at both doses. Generally, 5 ng/ml hrTNF-α was the maximum inhibitory dose. In the laying hen, a decrease in steroid production in response to cytokines may upset the steroid balance created by follicular hierarchy and inhibit or delay ovulation.