title: Effect of exertion on the stimulation of ornithine decarboxylase activity by growth hormone in rats.
abstract: To investigate the effect of stressful stimulation on tissue responsiveness to growth hormone (GH), we examined ODC activity as a measure of hepatic sensitivity to the hormone during forced exertion in rats. GH caused a 15-fold increase in ODC activity in the livers of resting rats at 3 hours after the injection of hormone. Forced walking in a rotating cylinder enhanced the effect of GH on ODC activity by up to 66% above the effect in resting rats, and this enhancement was positively related to the speed of rotation of the cylinder. These results suggest that tissue hypersensitivity to GH stimulation is a consequence of forced exertion. This hypersensitivity to GH would tend to compensate for the inhibitory effects of forced exertion on GH secretion in rats.
authors.affiliation: Department of Psychiatry, State University of New York, Stony Brook 11794-8101.
authors.forename: J V
authors.initials: JV
authors.lastname: Martin
authors.forename: R J
authors.initials: RJ
authors.lastname: Wyatt
authors.forename: W B
authors.initials: WB
authors.lastname: Mendelson
mesh_terms: D000818:Animals; D013006:Growth Hormone / Q000494:pharmacology*; D008099:Liver / Q000201:enzymology; D009955:Ornithine Decarboxylase / Q000378:metabolism*; D005082:Physical Exertion; D051381:Rats; D011919:Rats, Inbred Strains
chemical_list: D013006:Growth Hormone; D009955:Ornithine Decarboxylase