Abstract

Increased thymic weights have been reported in sheep selected for resistance to internal parasites and treatment with IGF-1 increases thymic and splenic weights in sheep, suggesting that IGF-1 may have a role in regulating immune function. This hypothesis was examined in four experiments using mice as a model. Expt 1 Unselected Swiss mice (n-24) were injected 2 x daily with 30 mg/d rhIGF-1 or saline for 26 days from 28 days of age. IGF-1 treatment increased spleen weight at a common body weight (118.2 vs 95.9, pooled standard error (PSE) = 6.2 mg, P<0.05), but did not affect thymic regression (thymic weights at the end of treatment: 85.5 vs 81.9, PSE = 4.0 mg). Expt 2 Unselected female Swiss mice (n=22, age = 84.8

YX, Sun, R Bickerstaffe, AR Bray, G Keeley, S Young, D O'Connell, and S Mason

Proceedings of the New Zealand Society of Animal Production, Volume 53, , 403-406, 1993