This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted 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 PABLO, F. D. Articles by PRUSS, R. M. Search for Related Content PubMed PubMed Citation Articles by PABLO, F. D. Articles by PRUSS, R. M.

Insulin Is Present in Chicken Eggs and Early Chick Embryos

Diabetes Branch, National Institute of Arthritis, Diabetes, Digestive, and Kidney Diseases, National Institutes of Health Bethesda, Maryland 20205

Address requests for reprints to: Dr. Jesse Roth, Diabetes Branch, Building 10, Room 8S–243, National Institute of Arthritis, Diabetes, Digestive, and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20205.

Abstract

We showed that insulin appears in the chick embryo before β-cells are recognizable, as well as in the egg constituents even before fertilization. Acid-ethanol extracts of 2- to 8-day-old embryos were gel-filtered on Sephadex G-50. The peak of immunoreactive insulin chromatographed in a position corresponding to that of authentic insulin. The immunoreactive insulin extracted from embryos was approximately 2 ng/g wet wt during early embryogenesis (days 2, 3, and 4), with a 2- to 3- fold increase by days 5 and 6, in conjunction with pancreatic development. The heads of the embryos contributed 22–23% of the total insulin on days 3 and 4, but only 5% by day 5. Based on its reactivity in a pork insulin RIA, chicken insulin RIA, and rat adipocyte bioassay, we concluded that the material is very similar to avian (chicken or turkey) rather than mammalian type insulin. Similar immunological and biological insulin-like activity [but at much lower concentrations (0.2–0.8 ng/ml)] were recovered from the gel-filtered acid-ethanol extracts of yolk and white of unfertilized and fertilized eggs. This study, which shows that insulin is present at a very early stage in ontogeny, extends observations that insulin is native to organisms that lack pancreatic islets, including flies, worms, and microbes.

Footnotes

^* Present address: Laboratory of Clinical Sciences, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland 20205.

Received March 4, 1982.

This article has been cited by other articles:

				Y. Hu, Y. Ni, L. Ren, J. Dai, and R. Zhao Leptin Is Involved in the Effects of Cysteamine on Egg Laying of Hens, Characteristics of Eggs, and Posthatch Growth of Broiler Offspring Poult. Sci., September 1, 2008; 87(9): 1810 - 1817. [Abstract] [Full Text] [PDF]

				C. Hernandez-Sanchez, E. Rubio, J. Serna, E. J. de la Rosa, and F. de Pablo Unprocessed Proinsulin Promotes Cell Survival During Neurulation in the Chick Embryo Diabetes, March 1, 2002; 51(3): 770 - 777. [Abstract] [Full Text] [PDF]

				B Diaz, J Serna, F De Pablo, and E. de la Rosa In vivo regulation of cell death by embryonic (pro)insulin and the insulin receptor during early retinal neurogenesis Development, January 4, 2000; 127(8): 1641 - 1649. [Abstract] [PDF]

				A. V. Morales, J. Serna, C. Alarcon, E. J. de la Rosa, and F. de Pablo Role of Prepancreatic (Pro)Insulin and the Insulin Receptor in Prevention of Embryonic Apoptosis Endocrinology, September 1, 1997; 138(9): 3967 - 3975. [Abstract] [Full Text] [PDF]