Stimulation of the Pituitary-adrenocortical Axis by Saikosaponin of Bupleuri Radix

• Published in: Chemical & pharmaceutical bulletin Vol. 29; no. 2; pp. 495 - 499
• Main Authors: HIAI, SUSUMU, YOKOYAMA, HIROOMI, NAGASAWA, TETSURO, OURA, HIKOKICHI
• Format: Journal Article
• Language: English
• Published: Japan The Pharmaceutical Society of Japan 01.01.1981; Japan Science and Technology Agency
• Subjects: Animals; diphenhydramine; Male; Oleanolic Acid - analogs & derivatives; Pituitary-Adrenal System - drug effects; Plants, Medicinal - analysis; Rats; Sapogenins - pharmacology; Saponins; Stimulation, Chemical
• ISSN: 0009-2363; 1347-5223
• DOI: 10.1248/cpb.29.495

The effects of saikosaponin-a, -c and -d, isolated from the roots of Bupleurum falcatum L., on plasma adrenccotrcotropin (ACTH) and corticosterone concentrations in unanesthetized or pentobarbital-anesthetized rats were determined by radioimmunoassay and by the competitive protein binding method. A single dose of saikosaponin-a (5 mg/kg, i. p.) or -d (2.5 mg/kg, i. p.) significantly increased plasma ACTH and corticosterone levels 30 and 60 min after the treatment, but saikosaponin-c at a dose of 100 mg/kg had no effect. Intraperitoneal administration of saikosaponin-a or -d, but not -c, induced a transient hyperglycemia and a transient hypoinsulinemia. Dexamethasone pretreatment depressed the saponin-induced increase of both corticosterone and glucose. Treatment with hexamethonium partially depressed the saponin-induced responses in plasma corticosterone, but treatment with diphenhydramine did not.