HOME HELP CONTACT US SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Hodgkinson, S. C. Articles by Gluckman, P. D. Search for Related Content PubMed Articles by Hodgkinson, S. C. Articles by Gluckman, P. D.

Competitive tracer binding studies using radio-iodinated insulin-like growth factor-I and -II (¹²⁵I-labelled IGF-I and ¹²⁵I-labelled IGF-II) together with size exclusion chromatography and IGF-I affinity chromatography have been used to characterize IGF binding protein activity in ovine tissue fluids. Binding proteins of >200, 150 and 40–50 kDa were revealed in these studies and shown to be widely distributed in body fluids. Thus, the > 200 kDa binding protein, which is IGF-II specific, is present in plasma from mature sheep, colostrum and follicular fluid as well as fetal sheep plasma. This may be the ovine equivalent of the soluble type-2 IGF receptor recently identified in rat serum. The presence of a 150 kDa binding protein, of mixed specificity for IGF-I and IGF-II, in fetal and mature sheep plasma was confirmed in these studies. This protein, previously believed to be restricted to vascular fluids, was also identified in mammary lymph, follicular fluid and as a minor component in vitreous humor. Binding proteins of 40–50 kDa were revealed in every fluid tested and multiple variants with distinct specificities were also suggested. This was investigated by IGF-I affinity chromatography using mature sheep plasma. Following passage through the affinity adsorbent, binding of ¹²⁵I-labelled IGF-I to proteins in the 40–50 kDa region was abolished but when ¹²⁵I-labelled IGF-II was used as tracer, a binding protein of 40–50 kDa was still observed.

Thus sheep plasma contains at least two 40-50 kDa binding proteins. The competitive tracer binding studies indicated that one such protein demonstrates mixed specificity for IGF-I and -II while the other strongly favours IGF-II.

Journal of Endocrinology (1989) 120, 429–438

This article has been cited by other articles:

				P. Froment, D. Seurin, S. Hembert, J. E. Levine, C. Pisselet, D. Monniaux, M. Binoux, and P. Monget Reproductive Abnormalities in Human IGF Binding Protein-1 Transgenic Female Mice Endocrinology, May 1, 2002; 143(5): 1801 - 1808. [Abstract] [Full Text] [PDF]

				K. D. Laugero and G. P. Moberg Energetic response to repeated restraint stress in rapidly growing mice Am J Physiol Endocrinol Metab, July 1, 2000; 279(1): E33 - E43. [Abstract] [Full Text] [PDF]

				K. D. Laugero and G. P. Moberg Summation of behavioral and immunological stress: metabolic consequences to the growing mouse Am J Physiol Endocrinol Metab, July 1, 2000; 279(1): E44 - E49. [Abstract] [Full Text] [PDF]