Endocrinology, Vol 117, 650-655, Copyright © 1985 by Endocrine Society

ARTICLES

Measurement of growth hormone and prolactin receptor turnover in rat liver

RC Baxter

To study the rate of disappearance of GH and PRL receptors in the livers of rats treated with cycloheximide, a technique has been devised for multiple sampling from the liver of each anesthetized rat. In rats treated with cycloheximide (1 or 5 mg/kg, iv), binding sites for both bovine GH and ovine PRL disappeared following first order kinetics over the 2-h sampling period. The half-time for the GH receptor was 30-40 min, equivalent to a rate constant of approximately 0.02 min-1. The half-time for the PRL receptor was 40-50 min, equivalent to a rate constant of approximately 0.015 min-1. At 0.1 mg/kg cycloheximide, slower disappearance rates were seen for both receptors, and the GH receptor showed a partial recovery. Over the same period, binding sites for insulin were unaltered at any cycloheximide dose. Assuming cycloheximide acts simply to inhibit new receptor synthesis, these rates represent the turnover time for GH and PRL receptors in rat liver.

This article has been cited by other articles:

				T. C. Brelje, L. E. Stout, N. V. Bhagroo, and R. L. Sorenson Distinctive Roles for Prolactin and Growth Hormone in the Activation of Signal Transducer and Activator of Transcription 5 in Pancreatic Islets of Langerhans Endocrinology, September 1, 2004; 145(9): 4162 - 4175. [Abstract] [Full Text] [PDF]

				P. van Kerkhof, M. Smeets, and G. J. Strous The Ubiquitin-Proteasome Pathway Regulates the Availability of the GH Receptor Endocrinology, April 1, 2002; 143(4): 1243 - 1252. [Abstract] [Full Text] [PDF]

				P. van Kerkhof, R. Govers, C. M. Alves dos Santos, and G. J. Strous Endocytosis and Degradation of the Growth Hormone Receptor Are Proteasome-dependent J. Biol. Chem., January 21, 2000; 275(3): 1575 - 1580. [Abstract] [Full Text] [PDF]

				D. Defalque, N. Brandt, J.-M. Ketelslegers, and J.-P. Thissen GH insensitivity induced by endotoxin injection is associated with decreased liver GH receptors Am J Physiol Endocrinol Metab, March 1, 1999; 276(3): E565 - E572. [Abstract] [Full Text] [PDF]

				R. Govers, P. van Kerkhof, A. L. Schwartz, and G. J. Strous Di-leucine-mediated Internalization of Ligand by a Truncated Growth Hormone Receptor Is Independent of the Ubiquitin Conjugation System J. Biol. Chem., June 26, 1998; 273(26): 16426 - 16433. [Abstract] [Full Text] [PDF]

				G. P. Frick, L.-R. Tai, W. R. Baumbach, and H. M. Goodman Tissue Distribution, Turnover, and Glycosylation of the Long and Short Growth Hormone Receptor Isoforms in Rat Tissues Endocrinology, June 1, 1998; 139(6): 2824 - 2830. [Abstract] [Full Text] [PDF]