Related Experiment Video
Updated: Aug 19, 2026

A RAPID Method for Blood Processing to Increase the Yield of Plasma Peptide Levels in Human Blood
Published on: April 28, 2016
Insulin-like growth factor-I down-regulates ghrelin receptor (growth hormone secretagogue receptor) expression in the
Jun Kamegai1, Hideki Tamura, Takako Shimizu
1Department of Medicine, Nippon Medical School, 1-1-5 Sendagi, Bunkyo-Ku, Tokyo 113-8603, Japan. jkamegai@nms.ac.jp
Abstract:
The effects of insulin-like growth factor-I (IGF-I) on the ghrelin receptor [growth hormone secretagogue receptor (GHS-R)] gene expression and on the GH response to GHS in rat pituitary cell cultures were examined. Pituitary GHS-R mRNA levels were decreased in a dose (0.01-10 nM)- and time (4-12 h)-dependent manner by IGF-I as measured with reverse transcriptase (RT)-PCR. The basal GH secretion was not influenced by the pretreatment with IGF-I (1 nM for 8 h); however, the GH response to the receptor ligand, a synthetic GHS, KP-102 (100 nM, 15 min), was significantly reduced by pretreatment with IGF-I. Thus, the present studies indicate that IGF-I could inhibit GH secretion at least in part by regulating the expression of the GHS-R.
Related Concept Videos
Glucagon-like Receptor Agonists
GLP-1, when administered in high doses intravenously, triggers insulin secretion, inhibits glucagon release, slows gastric emptying, reduces food intake, and restores normal insulin secretion. However, its rapid inactivation by the...
Regulation of Food Intake
Insulin: The Receptor and Signaling Pathways
TGF - β Signaling Pathway
GPCRs Regulate Adenylyl Cylase Activity
Two...
Hormones of the Pituitary Gland
The most abundantly secreted hormone from the anterior lobe is the growth hormone, which controls overall growth by...
