This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Copyright Permission Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by LEE, W.-H. Articles by HENRY, D. P. Search for Related Content PubMed PubMed Citation Articles by LEE, W.-H. Articles by HENRY, D. P.

Measurement of Insulin-Like Growth Factor-II in Physiological Fluids and Tissues. II. Extraction and Quantification in Rat Tissues^*

Lilly Research Laboratories, Eli Lilly Co., and the Departments of Pharmacology, Biochemistry and Molecular Biology, and Medicine, Indiana University School of Medicine Indianapolis, Indiana 46202

Abstract

The tissue distribution and developmental patterns of insulin-like growth factor-II (IGF-II) have not been investigated in rat tissues, primarily because of the lack of an efficient extraction method for IGF-II and a sensitive RIA. IGFII was extracted from rat tissues by formic acid, and the extract was heated at an acidic pH and treated with acetone. The removal of binding proteins was demonstrated by fast protein liquid chromatography size exclusion column and the elimination of a dilutional bias in the RIA. Using rat IGF-II as standard, we optimized a RIA for the quantification of IGF-II in rat tissues. In adult rats, IGF-II was found in all 15 tissues examined, with the highest concentration in the pituitary, followed by kidney, seminal vesicles, intestine, and serum. This distribution is not only different from that of IGF-I, but also differs from that reported for IGF-II mRNA and IGF-II receptors, suggesting that the rates of synthesis and/or metabolism of IGF-II are tissue dependent. Developmentally, IGF-II levels fell postnatally in most tissues, a pattern similar to that of IGF-II mRNA and IGF-II receptor. This developmental pattern supports the hypothesis that IGF-II is important in early growth and development. A relatively homogeneous distribution was observed in the adult rat brain, a distribution also different from that reported for IGF-II mRNA. In the pituitary, the highest concentration was found in the posterior pituitary, followed by the intermediate and anterior pituitary. In conclusion, IGF-II is found in many tissues of adult rats. This observation supports an autocrine and/or paracrine roles for IGF-II. (Endocrinology 128: 815–822, 1991)

Footnotes

^* Presented in part at the 71st Annual Meeting of The Endocrine Society, Seattle, WA, 1989.

Received July 30, 1990.

This article has been cited by other articles:

				V. Chandrashekar, C. R. Dawson, E. R. Martin, J. S. Rocha, A. Bartke, and J. J. Kopchick Age-Related Alterations in Pituitary and Testicular Functions in Long-Lived Growth Hormone Receptor Gene-Disrupted Mice Endocrinology, December 1, 2007; 148(12): 6019 - 6025. [Abstract] [Full Text] [PDF]

				A. De la Puente, L. Goya, S. Ramos, M. A. Martin, C. Alvarez, F. Escriva, and A. M. Pascual-Leone Effects of experimental diabetes on renal IGF/IGFBP system during neonatal period in the rat Am J Physiol Renal Physiol, December 1, 2000; 279(6): F1067 - F1076. [Abstract] [Full Text] [PDF]

				S Freier, O Weiss, M Eran, A Flyvbjerg, R Dahan, I Nephesh, T Safra, E Shiloni, and I Raz Expression of the insulin-like growth factors and their receptors in adenocarcinoma of the colon Gut, May 1, 1999; 44(5): 704 - 708. [Abstract] [Full Text] [PDF]

				G. GAYAN-RAMIREZ, F. VANDERHOYDONC, G. VERHOEVEN, and M. DECRAMER Acute Treatment with Corticosteroids Decreases IGF-1 and IGF-2 Expression in the Rat Diaphragm and Gastrocnemius Am. J. Respir. Crit. Care Med., January 1, 1999; 159(1): 283 - 289. [Abstract] [Full Text]

				P. Leblanc, A. L'Heritier, and C. Kordon Cryptic Gonadotropin-Releasing Hormone Receptors of Rat Pituitary Cells in Culture Are Unmasked by Epidermal Growth Factor Endocrinology, February 1, 1997; 138(2): 574 - 579. [Abstract] [Full Text] [PDF]

				S. Roth, M. P. Abernathy, W.-H. Lee, L. Pratt, S. Denne, A. Golichowski, and O. H. Pescovitz Insulin-Like Growth Factors I and II Peptide and Messenger RNA Levels in Macrosomic Infants of Diabetic Pregnancies Reproductive Sciences, March 1, 1996; 3(2): 78 - 84. [Abstract] [PDF]

				C. P. Kiritsy and S. E. Lynch Role of Growth Factors in Cutaneous Wound Healing: A Review Critical Reviews in Oral Biology & Medicine, January 1, 1993; 4(5): 729 - 760. [Abstract] [Full Text] [PDF]