To investigate the effects of early nutritional intervention on the serum insulin-like growth factor-1 （IGF1）

insulin-like growth factor binding protein 3 （IGFBP3）

intestinal development

and catch-up growth of intrauterine growth retardation （IUGR） rats by giving the IUGR new born rats different protein level diet. Methods IUGR rat model was built by starvation of pregnant female rats. Twenty-four IUGR pups and 8 normal pups were divided randomly into 4 groups: normal control group （C group）; IUGR control group（S group）

IUGR low-protein diet group （SL group）

and IUGR high-protein diet group （SH group）. Detected the serum IGF1

IGFBP3

body weight

body length

intestinal weight length

intestinal villi height （VH）

crypt depth （CD）

villi absorbing area （VSA）

mucous thickness （MT）

and disaccharidase at the 4th week. Results （1） The SH group showed the fastest catch-up growth

serum IGF1

IGFBP3

VH

and VSA were significantly higher than those of normal control group and IUGR control group. The intestinal weight and length

and the activities of lactase and saccharase of the SH group also reached the normal control group level. （2） The SL group kept on small size

the serum IGF1

IGFBP3

and most of intestinal histological indexes were all significantly lower than other groups. （3） IGF-1

IGFBP3 were positively correlated to intestinal VH

VSA

saccharase

body weight and length. Conclusions The serum IGF1 was a sensitive index to the catch-up growth. The early nutritional intervention of high-protein diet after birth is helpful for the catch-up growth of IUGR through promoting the intestinal development and the ab-sorption of nutrition