Naltrexone-induced changes in m-opioid-receptor binding in neonatal rat brain following chronic prenatal hypoxia
Hypoxia experienced by the fetus is beli ved to be a major cause of disturbed CNS function during childhood. During perinatal hypoxia endogenous opioids are released in large amounts and the developing brain in the last week of gestation may be influenced by circulating opioids, down-regulates n-opioid receptors in neonatal brain. The opioid antagonist, Naltrexone (N) blocks opiate receptors in the brain after chronic administration and can result in either up- or down-regulation of opioid receptors in the brain structures. To test the hypothesis that Naltrexone prevents prenatal chronic hypoxia-induced changes in (i-opioid receptor system in developing brain, we quantified optical density of the (i-opioid receptors in several areas of newborn rat brain. In CPu and ZG cerebral structures of rats long-lasting anoxia leads to the decrease in optical density of ^-opioid receptors. Naltrexone prevents optical density of ^-opioid receptors in CPu, OT, MMPoA and LMPoA structures from decreasing.