INDUCTION BY TUMOR-NECROSIS-FACTOR-ALPHA OF RAPID RELEASE OF IMMUNOREACTIVE AND BIOACTIVE LUTEINIZING-HORMONE FROM RAT PITUITARY-CELLS INVITRO

Tumor necrosis factor-α (TNF-α) is secreted by activated monocytes and other immune cells. This paper reports studies on the effects of TNF-α on the releases of pituitary hormones such as luteinizing hormone (LH), follicle-stimulating hormone, prolactin (PRL) and adrenocorticotropic hormone (ACTH). The addition of recombinant human TNF-α (rTNF-α) to cultures of pituitary cells resulted in significantly increased releases of gonadotropins, PRL, and ACTH for up to 30 min, but not later. rTNF-α, like GnRH, also stimulated the release of bioactive LH. In addition, rTNF-α induced production of an interleukin-6 (IL-6)-like molecule by pituitary cells. As IL-6 induces the releases of multiple hormones from pituitary cells, our data suggest that rTNF-α may stimulate the releases of multiple pituitary hormones through IL-6 production as well as by its direct action on pituitary cells.