Eur J Anat, 12 (2): 115-122 (2008)

Catch-up growth in intrauterine growth retarded rats: Its correlation with histomorphometric changes of the pituitary somatotrope cells

Oyhenart E.E., Quintero F.A., Orden A.B., Fucini M.C., Guimarey L.M., Carino M., Ferese C., Console G.M.

Centro de Investigaciones en Genética Básica y Aplicada (CIGEBA), Facultad de Ciencias Veterinarias, Universidad Nacional de La Plata (UNLP), Calles 60 y 118 S/N, CC 296, 1900 La Plata, Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), La Plata, Argentina; Cátedra de Antropología Biológica IV, Facultad de Ciencias Naturales y Museo, UNLP, La Plata, Argentina; Cátedra de Radiología, Facultad de Odontología, UNLP, La Plata, Argentina; Unidad de Endocrinología y Crecimiento, H.I.E.P., SSM Ludovica, La Plata, Argentina; Comisión de Investigaciones Científicas de la Provincia de Buenos Aires (CICPBA), Buenos Aires, Argentina; Cátedra de Citología, Histología y Embriología, Facultad de Ciencias Médicas, UNLP, La Plata, Argentina

ABSTRACT The aim of the present study was to examine the long-term effects of prenatal injure on body and craniofacial growth in intrauterine growth retarded (IUGR) animals and its correlation with histomorphometric changes of the pituitary somatotrope population. IUGR model was carried out by means of uterine vessels ligation in pregnant rats at 14th day of pregnancy. Control and sham-operated animals were also included. The animals were X-rayed at 1, 21, and 84 days of age. Body weight, neural and facial variables were measured. Pituitaries were processed for light microscopy and immunolabeled with anti-GH sera. Morphometry was performed by means of an image-analysis system. Data were processed by ANOVA, and Wilcoxon tests. Body weight was significantly lower in newborn IUGR rats compared with that of their control counterparts, even during postnatal growth. Both neurocranium and face were similarly affected at birth and weaning. At 84 days of age, despite facial growth exhibited a partial recovery, cranial volumes remained smaller in IUGR animals. Quantitative immunohistochemistry revealed a significant decrease in the volume and cell densities in IUGR compared to control age peers. Adequate nutritional and environmental conditions were insufficient to reverse the effects of a reduced uteroplacental blood supply on fetal growth. The timing and duration of the growth insult seem to be crucial for the occurrence of catch-up body weight and cranial growth in the rat. The lack of complete catchup in these IUGR animals may be associated to an alteration in the GH production.

Keywords: growth hormone, growth hormone antibody, age, animal experiment, animal model, animal tissue, antibody labeling, article, body weight, catch up growth, controlled study, correlation analysis, craniofacial development, face growth, female, fetus, fetus growth, growth hormone release, growth hormone secreting cell, hypophysis, immunohistochemistry, intrauterine growth retardation, male, maternal nutrition, morphometrics, nonhuman, placenta circulation, postnatal growth, pregnancy, prenatal injury, rat, skull, weaning