Oxygen and its effects on the developing brain

• Main Author: Shore, Hannah
• Published: University of Edinburgh 2014
• Subjects: 612.8
• Online Access: https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.726501

Survival following preterm birth is improving but with an associated increase in morbidity in the survivors in the form of learning difficulties, attention, dyspraxia and dyslexia. Retinopathy of prematurity is a disease of disordered vascularisation within the retina. One of the most significant risk factors for developing this disease is the use of postnatal oxygen. Within Edinburgh this has been examined in more detail in a rodent model of prematurity. Previous work has shown that these rat pups experience white matter injury when subjected to physiological variable oxygen. The following body of work looks at white matter injury in more detail. The vascularity within the rodent brain has been assessed both through histological study and magnetic resonance angiography (MRA). We hypothesise that the same disease process that is seen in the retinas of these infants is also occurring within the white matter of the brain. Rat pups reared in a variable oxygen appear to have more cerebral capillaries, which have an increased diameter when compared to rat pups reared in room air. Assessment by MRA shows that the larger cerebral vessels have a smaller volume in pups reared in oxygen when compared to room air. The human study was set up to look for differences in pathology seen between brains from stillborn infants and those who experienced a neonatal death. It has been shown that there appears to be a greater astrocytic response in brains from neonatal deaths when compared to stillbirths but no difference in expression of myelin basic protein (MBP). It has been shown that quantity of MBP expression increases in relation to an increase in gestational age. This body of work contributes to the discussions regarding what is deemed to be a safe level of oxygen to use within the neonatal unit.