NEWBORN RODENT AS A GOOD MODEL FOR PRETERM BRAIN

The many neurodevelopmental handicaps that very low birthweight infants experience suggest that preterm birth disrupts the genetically programmed pattern of brain genesis. To develop a clinically relevant model of the effect of preterm birth on developing brain, one must use an animal model that shows that the injury imposed results in neuropathological changes similar to those found in preterm infants and correlate these changes with behavioural outcomes. As in the preterm infant at the end of the second trimester, neuronal generation in the newborn rodent is complete in most regions, axonal and dendritic branching is robust, and synaptogenesis is just beginning.¹

Review of the literature suggests that oxygen deprivation is a major cause of neurodevelopmental disability in preterm infants.² Although intraventricular haemorrhage, periventricular leucomalacia, and ventriculomegaly are the most commonly recognised and best studied of these circulatory disturbances,² hypoxia is particularly prevalent among very low birthweight infants and is a common denominator of these abnormalities.³

Models of both hypoxia-ischaemia and hypoxia have been studied in newborn rodents, and the former results in focal injury to developing brain.⁴ In contrast, the exposure of …