Saturated fatty acids suppress adrenocorticotropic hormone (ACTH) release from rat anterior pituitary cells in vitro

• Published in: Comparative biochemistry and physiology. Part A, Molecular & integrative physiology Molecular & integrative physiology, 2004-02, Vol.137 (2), p.357-364
• Main Authors: Katoh, Kazuo, Asari, Mami, Ishiwata, Hiroko, Sasaki, Yasuyuki, Obara, Yoshiaki
• Format: Article
• Language: English
• Subjects: ACTH; Adrenocorticotropic Hormone - metabolism; Animals; Anterior pituitary cells; Arachidonic acid; Arachidonic Acid - pharmacology; Arginine Vasopressin - pharmacology; Arginine-vasopressin; Calcium - metabolism; Caprylates - pharmacology; Cells, Cultured; Corticotropin-Releasing Hormone - antagonists & inhibitors; Corticotropin-Releasing Hormone - pharmacology; CRF; Fatty Acids - pharmacology; Fatty Acids - physiology; Fatty Acids, Unsaturated - pharmacology; Fatty Acids, Unsaturated - physiology; Microscopy, Confocal; Pituitary Gland, Anterior - drug effects; Pituitary Gland, Anterior - metabolism; Rat; Rats; Saturated fatty acids; Synergistic release; Unsaturated fatty acids
• ISSN: 1095-6433; 1531-4332
• DOI: 10.1016/j.cbpb.2003.10.011

We studied whether fatty acids modify adrenocorticotropic hormone (ACTH) release induced by stimulation with corticotropin-releasing hormone (CRH) from rat anterior pituitary cells. Stimulation with CRH (0.01–100 nmol/l) significantly and concentration-dependently increased ACTH release, which was synergistically enhanced by the simultaneous stimulation with 1 nmol/l arginine-vasopressin. Addition of saturated fatty acids (butyrate, caprylate, laurate, palmitate and stearate) in a medium at 1 mmol/l, despite effects on the basal release, significantly reduced the ACTH release induced by CRH (1 nmol/l) stimulation. Caprylate suppressed ACTH release in a concentration-dependent manner. However, unsaturated C18 and C20 fatty acids (oleate, linolate, linolenate and arachidonate) at 1 mmol/l significantly increased the basal release, but none of them suppressed CRH (1 nmol/l)-induced ACTH release. In the presence of caprylate (1 mmol/l), CRH (1 nmol/l)-stimulated increase in cellular calcium ion concentration was diminished. From these results we conclude that saturated fatty acids have a suppressing effect on CRH-induced ACTH increase in primary cultured rat anterior pituitary cells.