Assessment of developmental changes in chicken and turkey insulin-like growth factor-II by homologous radioimmunoassay

McMurtry, J. P.; Rosebrough, R. W.; Brocht, Donna M.; Francis, G L; Upton, Zee; Phelps, P.

doi:10.1677/joe.0.1570463

Cited by 42 publications

(21 citation statements)

References 40 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Circulating IGF-II levels also increased with age (1 week vs 6 weeks of age) although with less contrast. In the chicken, previous data vary from the absence of post-hatch variations (Radecki et al 1997) to a fall from hatch up to at least 50 days of age (McMurtry et al 1998). In mammalian species, during the postnatal period, results differ widely between species with almost undetectable I-hIGF-I.…”

Section: Discussionmentioning

confidence: 95%

Insulin-like growth factors and body growth in chickens divergently selected for high or low growth rate

Beccavin¹,

Chevalier²,

Cogburn³

et al. 2001

Journal of Endocrinology

133

View full text Add to dashboard Cite

Insulin-like growth factors (IGFs) stimulate growth rate in a number of animal species and are likely to contribute to genetic variations of growth potential. The present study was designed to link levels of IGF-I and IGF-II mRNA and peptides with growth rate in divergently selected genotypes of chickens with high (HG) or low (LG) growth rates. Circulating IGF-I and -II and hepatic mRNA levels were measured under ad libitum feeding conditions from 1 to 12 weeks of age, and at 6 weeks of age under three different nutritional conditions (fed, fasted for 16 or 48 h, re-fed for 4 or 24 h after a 48-h fast). IGF binding proteins (IGFBPs) were also measured. Circulating IGFs increased with age and were higher in HG chickens from 1 to 6 weeks. They decreased with fasting and only IGF-II was fully restored after 24 h of re-feeding, while IGF-I remained low. A significant decrease in steady state IGF-I mRNA levels was also observed with fasting. Across the nutritional study, hepatic IGF-I mRNAs were significantly higher in HG chickens. Variations of IGF-II mRNA levels with nutritional state or genotype exhibited a similar trend. IGFBP (28, 34 and 40 kDa) levels increased with age, while only faint differences were observed between genotypes. IGFBP-28 transiently increased with fasting and was inversely related to blood glucose and insulin levels, suggesting that it is equivalent to mammalian IGFBP-1. In HG chickens, IGFBP-28 and IGFBP-34 levels decreased markedly following refeeding. Therefore, high and low growth rates were respectively associated with high and low IGF-I and -II levels, supporting the hypothesis of a stimulatory role for both IGFs during post-hatching growth of chickens.

show abstract

Section: Discussionmentioning

confidence: 95%

Insulin-like growth factors and body growth in chickens divergently selected for high or low growth rate

Beccavin¹,

Chevalier²,

Cogburn³

et al. 2001

Journal of Endocrinology

133

View full text Add to dashboard Cite

show abstract

“…Specifically important, IGF-I and II stimulate hepatic glycogen, RNA and protein synthesis (McMurtry et al, 1998;Lu, et al, 2007). IGFs were also found in amniotic fluid where they may play a role in regulating amino acid utilization Lu, et al, 2007).…”

Section: Control By Insulin-like Growth Factors I and Iimentioning

confidence: 99%

Important metabolic pathways in poultry embryos prior to hatch

Oliveira

Uni

Ferket

2008

World's Poultry Science Journal

147

127

View full text Add to dashboard Cite

“…Plasma thyroxine (T 4 ) and tri-iodothyronine (T 3 ) were measured as previously described (Vasilatos-Younken et al 1997). Plasma insulin, IGF-I and IGF-II were measured as described by McMurtry et al (1983McMurtry et al ( , 1994McMurtry et al ( , 1998, and tissue IGF-I was measured as described by Rosselot et al (1995). McMurtry et al (1994) demonstrated that chicken IGF-binding proteins (IGFBPs) are acid-labile, so that interference of IGF-I detection by IGFBPs is not a problem using the indicated method of acid/ethanol extraction.…”

Section: Plasma Hormones and Metabolitesmentioning

confidence: 99%

Altered chicken thyroid hormone metabolism with chronic GH enhancement in vivo: consequences for skeletal muscle growth

Vasilatos‐Younken¹,

Zhou²,

Wang³

et al. 2000

Journal of Endocrinology

Self Cite

View full text Add to dashboard Cite

In contrast to most vertebrates, GH reportedly has no effect upon somatic growth of the chicken. However, previous studies employed only one to two dosages of the hormone, and limited evidence exists of a hyperthyroid response that may confound its anabolic potential. This study evaluated the effects of 0, 10, 50, 100 and 200 µg/kg body weight per day chicken GH (cGH) (0-200 GH) infused i.v. for 7 days in a pulsatile pattern to immature, growing broiler chickens (9-10 birds/dosage). Comprehensive profiles of thyroid hormone metabolism and measures of somatic growth were obtained.Overall (average) body weight gain was reduced 25% by GH, with a curvilinear, dose-dependent decrease in skeletal (breast) muscle mass that was maximal (12%) at 100 GH. This profile mirrored GH dose-dependent decreases in hepatic type III deiodinase (DIII) activity and increases in plasma tri-iodothyronine (T 3 ), with both also maximal (74 and 108% respectively) at 100 GH. No effect on type I deiodinase was observed. At the maximally effective dosage, hepatic DIII gene expression was reduced 44% versus controls. Despite dose-dependent, fold-increases in hepatic IGF-I protein content, circulating IGF-I was not altered with GH infusion, suggesting impairment of hepatic IGF-I release. Significant, GH dose-dependent increases in plasma non-esterified fatty acid and glucose, and overall decreases in triacylglycerides were also observed. At 200 GH, feed intake was significantly reduced (19%; P<0·05) versus controls; however, additional control birds pair-fed to this level did not exhibit any responses observed for GH-treated birds.The results of this study support a pathway by which GH impacts on thyroid hormone metabolism beginning at a pretranslational level, with reduced hepatic DIII gene expression, translating to reduced protein (enzyme) expression, and reflected in a reduced level of peripheral T 3 -degrading activity. This contributes to decreased conversion of T 3 to its inactive form, thereby elevating circulating T 3 levels. The hyper-T 3 state leads to reduced net skeletal muscle deposition, and may impair release of GH-enhanced, hepatic IGF-I.In conclusion, GH has significant biological effects in the chicken, but profound metabolic actions predominate that may confound positive, IGF-I-mediated skeletal muscle growth.

show abstract

Assessment of developmental changes in chicken and turkey insulin-like growth factor-II by homologous radioimmunoassay

Cited by 42 publications

References 40 publications

Insulin-like growth factors and body growth in chickens divergently selected for high or low growth rate

Insulin-like growth factors and body growth in chickens divergently selected for high or low growth rate

Important metabolic pathways in poultry embryos prior to hatch

Altered chicken thyroid hormone metabolism with chronic GH enhancement in vivo: consequences for skeletal muscle growth

Contact Info

Product

Resources

About