Neural Circuits and Systems Neuroscience
Author: Ana Fabiola Macchione | email: ana.macchione@unc.edu.ar
Catalina Giacinto 1°, Tomás Palmeri 1°, Ana Fabiola Macchione 1°, Ana Fabiola Macchione 2°
1° Instituto de Investigaciones Psicológicas IIPsi-CONICET-UNC. Córdoba-Argentina.
2° Facultad de Psicología, UNC. Córdoba-Argentina.
Ethanol is commonly consumed during gestation and lactation, impacting on the fetus and neonate. EtOH affects neurovegetative functions, such as breathing. One of the main ethanol targets on the CNS is the serotonin (5HT) neurons that also are involved in breathing modulation. Preclinical studies, that employ chronic and severe EtOH consumption during pregnancy and lactation, showed a decrease in the number of 5HT-neurons and 5HT levels in the raphe system. However, the status of the 5HT-system in animal models with low/moderate neonatal EtOH exposure are understudied. In previous studies we found that the first EtOH intoxication decreases the 5HT levels in the raphe obscurus-ROb, but the pre-exposure to the drug induces a compensatory effect unaltering the 5HT levels in this area. In this study we evaluate 5HT levels by immunofluorescence in other areas of the medullary raphe (ROb, magnus and pallidus) in neonate rats exposed to EtOH and challenged with hypoxia (3 episodes of 5 min). At postnatal days-PD 3, 5 and 7, pups were administered with EtOH or vehicle (2.0 or 0.0g/kg, ig). At PD 9, pups were EtOH re-intoxicated or not (vehicle-administered). This design allows us to discriminate the effects of EtOH pre-exposure from those of acute EtOH intoxication. These results become important when associating the function of the medullary raphe on respiratory response and breathing disturbances induced by EtOH in neonate rats and humans, such as Sudden Infant Death Syndrome.