HUMAN NEONATES PRENATALLY EXPOSED TO ETHANOL EXHIBIT RESPIRATORY DEPRESSIONS WHEN EXPOSED TO THE OLFACTORY CUES OF THE DRUG

ANUNZIATA, F; MITRANO, A.S.; PONTORIERO, R.; FERREYRA, M.E.; MACCHIONE, A.F.; AHUMADA, L.A.; MOLINA, JC

Puerto Varas

Encuentro; VIII LASBRA INTERNATIONAL MEETING: Neurobiological basis of alcoholism: from molecules to behavior; 2017

Following maternal ethanol ingestion fetuses process the drug´s chemosensory cues present in utero. The unborn organism is also capable of associating these cues with physiological effects of the drug. In altricial mammals, ethanol suppresses fetal breathing movements. This effect appears to be associated with the drug´s sensory cues. Later exposure to ethanol odor elicits conditioned breathing depression. The present study analyzed whether different patterns of ethanol use or abuse during human pregnancy affects respiratory rates in neonates re-exposed to the odor of the drug. Mothers were classified as infrequent, moderate or excessive drinkers in accordance with ethanol ingestion patterns during pregnancy. Forty-three neonates were tested in terms of respiratory and cardiac frequencies when primarily exposed to ethanol or to lemon odor. No significant differences were observed across maternal groups in terms of neonatal body weights and sizes, head circumferences, Apgar scores, gestational ages, cardiac frequencies or oxygen saturation scores. When neonates were stimulated with lemon odor, respiratory frequencies were similar across maternal groups. Exposure to ethanol odor significantly affected breathing rates as a function of maternal drinking patterns. During the initial phase of the test, babies representative of excessive drinkers exhibited a significant decrease in breathing rates relative to neonates delivered by infrequent drinkers. The results indicate that neonatal breathing alterations are observed as a function of relatively high ethanol exposure during pregnancy and olfactory neonatal re-exposure to the drug´s chemosensory properties. This alteration suggests that ethanol-related learning processes are capable of disrupting the physiological well-being of human neonates.