Journal of Clinical Endocrinology & Metabolism, Vol 65, 617-623, Copyright © 1987 by Endocrine Society

ARTICLES

Characterization of serum growth hormone (GH) and insulin-like growth factor I in active acromegaly with minimal elevation of serum GH

WH Daughaday, RH Starkey, S Saltman, JR Gavin 3d, B Mills-Dunlap and E Heath- Monnig
Department of Medicine, Washington University School of Medicine, St. Louis, Missouri 63110.

In most patients with acromegaly basal serum GH concentrations are elevated and remain above 5 micrograms/L after oral glucose administration. In some patients, however, serum insulin-like growth factor I (IGF-I) concentrations are elevated with only minimal elevations of serum GH. We studied the serum GH and IGF-I of two such patients to determine whether these peptide hormones are normal in this clinical situation. The serum GH of these patients was found to bind normally to receptors of the IM-9 lymphocyte. The elution pattern of IGF-I extracted from the patients' serum was similar to that of (Thr59) human IGF-I after passage through a Bio-Rad P-60 column in 0.5 M acetic acid. The IGF-I was further characterized by isoelectric focusing and C18 reverse phase high pressure liquid chromatography (HPLC). The isoelectric points of the IGF-I components were similar to those of IGF- I in normal serum. The IGF-I in one patient had two components by HPLC, while that of the other patient had only one major component. The IGF-I components isolated by HPLC were normally active in stimulating [3H] alpha-aminoisobutyric acid uptake by normal human fibroblasts. The elevated serum IGF-I concentrations of these two patients were GH dependent. Transsphenoidal adenomectomy in one patient resulted in a decline in serum IGF-I to a high normal concentration. Lowering the serum GH to subnormal concentrations by the administration of the somatostatin analog SMS 201-995 (Sandoz) restored normal IGF-I concentrations in the second patient. We conclude that the GH and IGF-I of these two patients cannot account for their apparent enhanced GH responsiveness.

This article has been cited by other articles:

				O. Alexopoulou, M. Bex, R. Abs, G. T'Sjoen, B. Velkeniers, and D. Maiter Divergence between Growth Hormone and Insulin-Like Growth Factor-I Concentrations in the Follow-Up of Acromegaly J. Clin. Endocrinol. Metab., April 1, 2008; 93(4): 1324 - 1330. [Abstract] [Full Text] [PDF]

				J. J. Puder, S. Nilavar, K. D. Post, and P. U. Freda Relationship between Disease-Related Morbidity and Biochemical Markers of Activity in Patients with Acromegaly J. Clin. Endocrinol. Metab., April 1, 2005; 90(4): 1972 - 1978. [Abstract] [Full Text] [PDF]

				E. V. Dimaraki, C. A. Jaffe, R. DeMott-Friberg, W. F. Chandler, and A. L. Barkan Acromegaly with Apparently Normal GH Secretion: Implications for Diagnosis and Follow-Up J. Clin. Endocrinol. Metab., August 1, 2002; 87(8): 3537 - 3542. [Abstract] [Full Text] [PDF]

				S. Melmed, I. Jackson, D. Kleinberg, and A. Klibanski Current Treatment Guidelines for Acromegaly J. Clin. Endocrinol. Metab., August 1, 1998; 83(8): 2646 - 2652. [Abstract] [Full Text]

				A. L. Barkan, I. Halasz, K. J. Dornfeld, C. A. Jaffe, R. D. Friberg, W. F. Chandler, and H. M. Sandler Pituitary Irradiation Is Ineffective in Normalizing Plasma Insulin-Like Growth Factor I in Patients with Acromegaly J. Clin. Endocrinol. Metab., October 1, 1997; 82(10): 3187 - 3191. [Abstract] [Full Text] [PDF]

				C. L. Boguszewski, G. Johannsson, B.-A. Bengtsson, A. Johansson, B. Carlsson, and L. M. S. Carlsson Circulating Non-22-Kilodalton Growth Hormone Isoforms in Acromegalic Men before and after Transsphenoidal Surgery J. Clin. Endocrinol. Metab., May 1, 1997; 82(5): 1516 - 1521. [Abstract] [Full Text] [PDF]

				J. L. Stock, M. R. Warth, B. T. Teh, J. A. Coderre, J. H. Overdorf, G. Baumann, R. L. Hintz, M. L. Hartman, B. R. Seizinger, C. Larsson, et al. A Kindred with a Variant of Multiple Endocrine Neoplasia Type 1 Demonstrating Frequent Expression of Pituitary Tumors but Not Linked to the Multiple Endocrine Neoplasia Type 1 Locus at Chromosome Region 11q13 J. Clin. Endocrinol. Metab., February 1, 1997; 82(2): 486 - 492. [Abstract] [Full Text] [PDF]

				D A Sweetser, E H Birkenmeier, P C Hoppe, D W McKeel, and J I Gordon Mechanisms underlying generation of gradients in gene expression within the intestine: an analysis using transgenic mice containing fatty acid binding protein-human growth hormone fusion genes. Genes & Dev., October 1, 1988; 2(10): 1318 - 1332. [Abstract] [PDF]