INTRAUTERINE GROWTH RETARDATION IN RATS: BONE MODIFICATIONS AND SEXUAL DIMORPHISM AT BIRTH

LUNA ME; QUINTERO FA; CESANI MF; FUCINI MC; GUIMAREY LM; VILLANUEVA M; PRIO V; OYHENART EE

La Plata, Argentina

Congreso; X Congreso de la Sociedad de Ciencias Morfológicas de La Plata y 7mas Jornadas de Educación; 2008

Soceidad de Ciencias Morfológicas de La Plata

The intrauterine growth retardation (IUGR) is characterized by a reduction of the fetal growth rate. Most studies about IUGR analyze growth through an evaluation of birth weight. However, few of them investigate the postcranial skeleton. The objectives of this paper, based on an experimental study, were to evaluate: a) the IUGR effect on different bone segments at birth and b) the specific responses in each sex. Wistar rats were divided in groups: Control, IUGR and Sham-operated. The IUGR was induced by partial bending of both uterine vessels at day 1 of pregnancy. The animals were x-rayed at birth. Humerus, radius and femur lengths and widths, and pelvic length and inter-ischial, inter-pubic and pubic widths, were measured on each Rx. Data were analyzed by ANOVA and LSD post hoc test. The “F” values indicated significant differences for treatment in the majority of the analyzed variables and it showed no significant differences between sexes. Nevertheless, the IUGR females in comparison with Sham-operated females showed percentually smaller relative differences. In males, sham-operated and IUGR males showed significant differences in pelvic lengths and widths, humerus, radius, femur and tibia widths. In females, there were only significant differences for humerus widths, radius length and width and femur and tibia widths. It can be concluded that reduced placental blood supply causes a differential delay of the appendicular skeleton growth. Pelvic length was more affected than the length of the limbs. In turn, the widths were more affected than the lengths. Under more disadvantageous circumstances of IUGR females were more affected than males.