Do Astrocytes Play a Role in Mediating Morphine Effects in Infants? Poster 14

Morphine is routinely used to manage surgical pain in juvenile and adult patients. Infants in the neonatal ICU have better outcomes if pain is managed with morphine. However, up to half of infants treated with morphine become... [ view full abstract ]

Morphine is routinely used to manage surgical pain in juvenile and adult patients. Infants in the neonatal ICU have better outcomes if pain is managed with morphine. However, up to half of infants treated with morphine become dependent, and need to be weaned off of the medication. The long term affects on brain development are not known. Astrocyte glial cells in the brain have been implicated in modulating effects of morphine. It is well-established that neuronal injury activates astrocytes to enhance their neuroprotective function. We hypothesized that chronic morphine exposure would similarly activate astrocytes in neonates. Using a rat model, we measured astrocyte activation in a region of the brain implicated in mediating morphine effects. To examine age dependence of astrocyte activation, rats were either chronically administered morphine 1.) only as neonates, 2.) as neonates and adults, or 3.) only as adults. A control group was given control saline at both ages. Although a qualitative difference in astrocyte morphology (swelling) was observed in rats who received chronic morphine administration, we did not detect a statistically significant difference in astrocyte activation between any of the test groups. We conclude that morphine may not activate astrocytes in this region of the brain.