Lack of prostaglandin involvement in the mitogenic effect of TSH on canine thyroid cells in primary culture

AbstractThe production of prostaglandin E2 (PGE2) by cultured dog thyroid cells was high in a serum-containing medium and low in a serum-free, completely defined medium. Thyrotropin (TSH) and epidermal growth factor (EGF), two mitogenic factors for these cells, did not stimulate PGE2 release. Indomethacin, at a concentration which completely inhibited PGE2 production, had no effect on thyroid cell multiplication and DNA synthesis stimulated by TSH and EGF. It is concluded that cyclooxygenase products are not involved in the proliferation of canine thyroid cells and its control by TSH