This paper addresses the effect of a reduction of uterine blood flow (RUB) on postcranial bone growth in rats. The objectives were: (1) to discover and characterize the changes evoked by growth retardation through a reduction in placental blood flow, (2) to see if the resulting growth retardation is different in each bone, and (3) to analyze any sex-specific features. RUB was induced by the partial bending of uterine vessels at day 1 of pregnancy. Control and sham-operated animals were also included. The animals were X-rayed at birth. The lengths and widths of the humerus, radius, and femur and pelvic length, interischial, interpubic, and pubic widths were measured. Data were analyzed by ANOVA and LSD post hoc tests. The intersubject analysis showed significant differences between groups and non-significant differences between sexes. In males, sham-operated and RUB showed significant differences in pelvic lengths and widths, and humeral, radial, femoral, and tibial widths. In females, there were significant differences only for humeral widths, radial lengths and widths, and femoral and tibial widths. We conclude that reduced blood flow delays appendicular bone growth as observed at birth. Pelvic length was more affected than that of the limbs. The widths of the pelvic and limbs bones, in turn, were more altered than the lengths, and the growth of the males more than that of the females. Partial bending of uterine vessels compromised postcranial growth, though under such disadvantageous circumstances the females proved to be more capable of growing and thus more resilient than the males.

RESUMEN El objetivo fue analizar en animales con retardo prenatal de crecimiento (RPC) el efecto de la subnutrición proteico-calórica lactacional y postlactacional sobre la morfología craneofacial, particularizando en el crecimiento de los componentes funcionales neural y facial. Ratas Wistar fueron divididas en los grupos: Control, RPC (inducido por ligamiento parcial de ambas arterias uterinas el día 15 de gestación) y Sham-operado (con igual técnica quirúrgica que RPC aunque sin ligamiento de las arterias). A su vez, el grupo RPC se dividió en: (a) crías lactantes de madres con nutrición normal y a partir del destete alimentadas ad-libitum y (b) crías lactantes de madres con restricción alimentaria del 25% y a partir del destete alimentadas con el 50% de lo consumido por un animal control. Se tomaron radiografías a las edades 1, 21, 42, 63 y 84 y se midieron longitud, PALABRAS CLAVE crecimiento craneofacial; desnutrición pre y postnatal; craneometría funcional ancho y altura de los componentes neural y facial. Se calcularon los índices volumétricos neural y facial y morfométrico neurofacial. Se aplicaron ANOVA y pruebas post-hoc y se calcularon diferencias porcentuales entre medias. Los resultados permitieron concluir que el estrés primario ocurrido durante la vida intrauterina resulta crítico en lo inmediato y en la vida postnatal, ya que aun mediando normonutrición postnatal el retardo de crecimiento perdura. Además, cuando al estrés prenatal le continúa restricción nutricional postnatal los efectos adversos son aditivos provocando retardo del crecimiento aún mayor. Finalmente, mientras que el componente neural es más resistente a las deficiencias nutricionales, el facial presenta mayor plasticidad, hecho que se evidencia en cambios de forma. Rev Arg Antrop Biol 18(1), 2016. doi:10.17139/raab.2016.0018.01.04 KEY WORDS craniofacial growth; prenatal and postnatal undernutrition; functional craniometry ABSTRACT The aim of the study was to analyze the effect of protein-calorie malnutrition during lactation and post-lactation on craniofacial morphology in intrauterine growth-retarded (IUGR) animals, particularly in the neural and facial functional components. Wistar rats were divided into the following groups: Control, IUGR (induced by partial bending of both uterine vessels at day 15 of gestation), and sham-operated (with the same surgical technique as IUGR, but without vessel bending). The IUGR group was further divided into (a) nursing pups of mothers with normal nutrition and fed ad-libitum at weaning, and (b) nursing pups of mothers with 25% food restriction and fed with 50% of the food ingested by controls at weaning. Radiographs were taken at 1, 21, 42, 63, and 84 days. Neural and facial length, width and height were measured, and neural and facial volumetric and morphometric indices were calculated. ANOVA and post-hoc tests were applied, and percentage differences between means were determined. Results showed that intrauterine stress is critical during early and postnatal life, since even when postnatal ...

The goal of this study was to analyse the effect of growth hormone (GH) on catch-up growth of functional facial (splanchnocranial) and neurocranial components in rats with intrauterine growth retardation (IUGR). Wistar rats were divided into the following groups: control (C), sham-operated (SH), IUGR, and IUGR + GH. IUGR was surgically induced and GH was administered between 21 and 60 days of age. Radiographs were obtained at 1, 21, 42, 63, and 84 days of age in order to measure length, width, and height of neurocranium (NL, NW, and NH) and face length, width, and height (FL, FW, and FH). Analysis of variance was performed at 1 day of age and a principal components analysis (PCA) at 84 days of age. Neurocranial and facial volumetric indexes were calculated as NVI = (3)√NL × NW × NH and FVI = (3)√FL × FW × FH, respectively, and adjusted by non-linear regression analysis. On postnatal day 1, there were significant differences between SH and IUGR (P < 0.01). Also, in both genders, final neurocranial volume was similar between SH and IUGR + GH groups, while the IUGR group had the lower value (P < 0.01). Final facial volume was similar among the three groups. In both genders, facial growth rates were SH = IUGR > IUGR + GH (P < 0.01). The first axis of the PCA exhibited size effect and the second axis showed shape effect. Reductions of placental blood flow modify cranial growth. The functional neurocranial and facial components in rats with IUGR presented different recovery strategies through modular behaviour, mainly related to modifications of growth rate as response to GH administration.