• Anterior pituitary gland;
  • cytokine-induced neutrophil chemoattractant;
  • folliculo-stellate cell;
  • herbal medicine;
  • Unkei-to

PROBLEM: We previously reported that a cytokine-induced neutrophil chemoattractant (CINC) was produced in the pituitary gland and that it influenced anterior pituitary hormone release. In this study we investigated the effect of Unkei-to, a Japanese herbal medicine, on CINC production in the rat anterior pituitary gland and the pituitary folliculo-stellate-like cell line (TtT/GF).

METHOD OF STUDY: Dispersed normal anterior pituitary cells and the folliculo-stellate-like cell line TtT/GF were used to test the effect of Unkei-to on CINC secretion and CINC mRNA accumulation. Concentrations of CINC in the conditioned media were measured by an enzyme-linked immunosorbent assay, and levels of CINC mRNA were analyzed by Northern blot analysis.

RESULTS: Unkei-to (20 μg/ml) significantly increased the secretion of CINC by normal anterior pituitary cells within 12 hr of incubation. Unkei-to also stimulated CINC secretion from TtT/GF cells in a time- and dose-dependent manner. Unkei-to (20 μg/ml) increased CINC mRNA accumulation in TtT/GF cells within 3 hr of incubation and also caused a 13-fold increase in the secretion of CINC from TtT/GF cells compared with the vehicle group within 24 hr of incubation. Finally, we found that some of the Unkei-to's ingredients, Evodiae fructus and Pinelliae tuber, markedly stimulated CINC secretion from TtT/GF cells.

CONCLUSIONS: Our results will help to elucidate the mechanism behind the clinical effect of Unkei-to on the anterior pituitary gland. They also suggested the presence of special substances, which stimulate CINC secretion, within Unkei-to's ingredients such as E. fructus and P. tuber.