Fellow in Neonatal-Perinatal Medicine UH Rainbow Babies & Children's Hospital Cleveland, Ohio, United States
Background: Apnea of prematurity is a common cause of short- and long-term morbidity in preterm infants. The nucleus tractus solitarius (nTS) of the brainstem exerts significant control of respirations through the activity of the large conductance calcium- and voltage-activated K+ channel (BK) as well as the small conductance calcium-activated K+ channels (SK1, SK2, and SK3). There is a growing body of evidence supporting the association of apnea in neonates with ethanol (EtOH) exposure in utero as demonstrated by the association of maternal ethanol abuse with sudden infant death syndrome. This association has been replicated in several animal models: EtOH given to rat pups (which are equivalent to third trimester fetuses or preterm infants) resulted in altered response to hypoxia and EtOH given to neonatal mice has shown to reduce the volume of the brainstem. Our group has previously shown that EtOH can cause redistribution of proteins into and out of lipid rafts (LR), dynamic membrane microdomains that serve as signaling platforms, thus altering their functions. Both the BK and SK ion channels have been reported to be lipid raft associated proteins that are important in regulating the neuronal activity of the nTS. Objective: To study the effects of EtOH on the lipid raft distribution of BK and SK channels in the nTS in a rat pup model of prematurity Design/Methods: On postnatal day (P) 5, Sprague Dawley rat pups divided by sex were gavaged with intralipid mixed with EtOH to provide 5.25 g/kg/day of EtOH or isovolumetric and isocaloric intralipid mixed with sucrose. The nTS was dissected, homogenized and lipid rafts isolated into LR and non-LR pools. The proportion of each channel within the LR pool was determined. Data will be analyzed by 1 way ANOVA followed by post hoc pairwise analysis. Protocol and care of animals was approved by institution’s IACUC. Data currently being collected, with goal completion in March, data analysis time will be minimal.
