PONDERAL GROWTH IN RATS WITH INTRAUTERINE GROWTH RETARDATION TREATED WITH GROWTH HORMONE ADJUSTED BY NONLINEAR REGRESSION

QUINTERO FA, CASTRO L, CESANI MF, FUCINI MC, LUNA ME, OYHENART EE, GUIMAREY LM

Chile

Congreso; XLV Reunión de la Sociedad Latinoamericana de Investigación Pediátrica.; 2007

SLAIP

Objective: The aims of this study was to evaluate the effect of growth hormone (GH) treatment on ponderal growth in intrauterine growth retarded (IUGR) rats. Methods: Wistar rats were asigned to the groups: Control (C), IUGR and IUGR-GH. IUGR was induced by partial obstruction of uterine vessels at 14th day of pregnancy. GH was injected from 21 (weaning) to 60 days of age (Genotropin®3.0 mg/kg/day). Animals received stock diet ad libitum. Body weight was registered weekly, from birth to 84 days of age. Data of weight of males and females were adjusted by regression curves. Control group was taken as parameter. Both curves were adjusted to the general equation: Log (weight)  (1/age)*treatment. Results: In males R2 adj  0.9616; F  2339 (p  2.2e-16); Intercet 6.65 (p  2e-16); I(1/age)75.175 (p  2e-16); Size IUGR0.15245 (p  0.00); Size IUGR-GH0.021 (n/s); I(1/age)*IUGR  1.73 (n/s); I(1/age)*IUGR-GH4.98 (p  0.00).In females: R2 adj 0.100 (p  0.00); Size IUGR-GH  0.06 (n/s); I(1/age)*IUGR 1.36 (n/s); I(1/age)*RPC-GH3.94 (p  0.01). Results: These results showed thatfinal weights of IUGR-GH animals became closer to control values, while that of IUGR aresignificantly lower. Weight gain rates were similar between Sham and IUGR, but lower in IUGR-GH.Conclusion: It is concluded that catch up growth in IUGR-GH implies an adequacy in rate of weight gain to an increase of tempo of growth.