The Effect of Ginsenosides on Adrenocorticotropin Secretion in Primary Culture of Rat Pituitary Cells

Abstract

The effect of ginsenoside-Rb₁, -Rc, -Rd, -Re, and Rg₁ on adrenocortiocotropin (ACTH) secretion was examined using a primary culture of pituitary cells. Ginsenoside-Rg₁, but not other ginsenosides, stimulated the secretion of ACTH. Ginsenoside-Rg₁ was found to stimulate ACTH secretion in a dose-dependent fashion; the half maximal response occurred at ca. 2.8 µM; the maximum content of ACTH was obtained at 10 µM of ginsenoside-Rg₁. The stimulation of ACTH secretion by ginsenoside-Rg₁ was observed at 15 min after the treatment. Intracellular adenosine 3′, 5′-cyclic monophosphate (cyclic AMP) increased significantly at 10 minute after treatment with ginsenoside-Rg₁. Although the increased plasma corticosterone level in a rat treated with ginsenoside-Rb₁, -Rc, -Rd, and -Re is considered as the result of stimulated ACTH secretion, in this study, it is suggested that ACTH secretion is not caused by direct action of these ginsenosides to hypophysis.