TweetFJYFFHK
TweetFailure of exogenous IGF-I to restore normal growth in rats submitted to dietary zinc
Dietary zinc deficiency in rats causes growth retardation associated with decreased circulating IGF-I concentrations. To investigate the potential role of low IGF-I in this condition, we attempted to reverse the growth failure by administration of exogenous IGF-I. Rats were fed for 4 weeks a zinc-deficient diet (ZD, Zn 0 ppm) or were pair-fed a zinc-normal diet (PF, Zn 75 ppm). We compared the anabolic action of recombinant human (rh) IGF-I infused at the dose of 120 microg/day for the last experimental week in ZD, PF and freely fed control (CTRL) rats. Zinc deficiency caused growth stunting (weight gain 47% of PF; P<0.001), decreased circulating IGF-I (52% of PF; P<0.01) and liver IGF-I mRNA (67% of PF; P<0.01). Serum insulin-like growth factor-binding protein-3 (IGFBP-3) assessed by ligand blot was also reduced in ZD rats (65% of PF; P<0. 01). While exogenous IGF-I increased body weight in CTRL (+12 g; P<0. 01) and PF (+7 g; not significant) animals, growth was not stimulated in ZD rats (-1.5 g) in comparison with the corresponding untreated groups. However, circulating IGF-I and IGFBP-3 levels were restored by IGF-I infusion to levels similar to those in untreated CTRL rats. In conclusion, restoration of normal circulating levels of IGF-I and IGFBP-3 by rhIGF-I infusion fails to reverse the growth retardation induced by zinc deficiency. These results suggest that growth retardation related to zinc deficiency is not only caused by low serum IGF-I concentrations, but also by inhibition of the anabolic actions of IGF-I.
Disclaimer: Steroid use is illegal in a vast number of countries around the world. This is not without reason. Steroids should only be used when prescribed by your doctor and under close supervision. Steroid use is not to be taken lightly and we do not in any way endorse or approve of illegal drug use. The information is provided on the same basis as all the other information on this site, as informational/entertainment value.
Please take the time to read these threads!
Fitness Geared Shoutbox rules
FG member signature rules
Fitness Geared Forum Rules
https://www.fitnessgeared.com/forum/f334/
https://www.fitnessgeared.com/forum/f283/
https://www.tgbsupplements.com/
TweetFJYFFHK
TweetGHJLGJKL
TweetRYUIRYIRY
Tweetylutut
Tweetljlhjl
Tweeterturturtu
Tweetrrurturt
Tweetfhfghsfgh
Tweetkfjrejhkldruiyrkrldrjdkrj,mdkjfydskg,bmgjb krjtumm ithry768rdiirk6k6ejeys46w36t4jk
Tweetywrtywrty