Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
2000-5-25
pubmed:abstractText
Classical provocative stimuli of GH secretion such as insulin-induced hypoglycaemia, arginine, clonidine, glucagon and levodopa have been widely used in clinical practice for approximately 30 years. On the other hand, in the last 10 years new potent stimuli of GH secretion have been proposed, but an extensive comparison with the classical ones has rarely been performed, at least in adults. In order to compare the GH-releasing activity of old and new provocative stimuli of GH secretion, and to define the normative values of the GH response, in 178 normal adults (95 males, 83 females; age range: 20-50 years, all within +/-15% of their ideal body weight), we studied the GH response to: insulin-induced hypoglycaemia (ITT, 0.1IU/kg i.v.), arginine (ARG, 0.5g/kg i.v.), clonidine (CLO, 300 microg/kg p.o.), glucagon (GLU, 1mg i.m.), pyridostigmine (PD, 120mg p.o.), galanin (GAL, 80pmol/kg per min), GH-releasing hormone (GHRH, 1 microg/kg i.v.), GHRH+ARG, GHRH+PD, hexarelin, a GH-releasing protein (HEX, 2 microg/kg i.v.) and GHRH+HEX (0.25 microg/kg i.v.). The mean (+/-s.e.m.) peak GH response to ITT (21.8+/-2.8, range: 3.0-84.0 microg/l) was similar to those to ARG (18.0+/-1.6, range: 2.9-39.5 microg/l) or GLU (20. 5+/-2.2, range: 10.6-36.9 microg/l) which, in turn, were higher (P<0. 001) than those to CLO (8.2+/-1.6, range: 0.3-21.5 microg/l), PD (9. 6+/-1.1, range: 2.2-33.0 microg/l) and GAL (9.3+/-1.1, range: 3.9-18. 3 microg/l). The GH response to GHRH (19.1+/-1.5, range: 2.7-55.0 microg/l) was similar to those after ITT, ARG or GLU but clearly lower than those after GHRH+ARG (65.9+/-5.5, range: 13.8-171.0 microg/l) and GHRH+PD (50.2+/-4.6, range: 17.7-134.5 microg/l) which, in turn, were similar. The GH response to HEX (55.3+/-5.5, range: 13.9-163.5 microg/l) was similar to those after GHRH+ARG and GHRH+PD but lower (P<0.001) than that after GHRH+HEX (86.0+/-4.3, range: 49. 0-125.0 microg/l) which was the most potent stimulus of GH secretion. In this adult population the third centile limits of peak GH response to various stimuli were the following: ITT: 5.3; ARG: 2.9; CLO: 1.5; GLU: 7.6; PD: 2.2; GAL: 4.0; GHRH: 5.0; GHRH+ARG: 17.8; GHRH+PD: 17.9; HEX: 21.6; GHRH+HEX: 57.1. These results confirm that, among classical provocative tests of GH secretion, ITT followed by ARG and GLU are the most potent ones and possess clear limits of normality. GHRH+ARG or PD and HEX are strong stimuli of GH secretion which, however, is maximally stimulated by a combination of GHRH and a low dose of HEX. It is recommended that each test is used with appropriate cut-off limits.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0804-4643
pubmed:author
pubmed:issnType
Print
pubmed:volume
142
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
347-52
pubmed:dateRevised
2011-11-17
pubmed:meshHeading
pubmed:year
2000
pubmed:articleTitle
Comparisons among old and new provocative tests of GH secretion in 178 normal adults.
pubmed:affiliation
Division of Endocrinology, Department of Internal Medicine, University of Turin, Turin, Italy.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, Non-U.S. Gov't