Loss of neonatal hypoxia tolerance after prenatal nicotine exposure: Implications for sudden infant death syndrome

摘要: Maternal cigarette smoking has a high correlation with sudden Infant Death Syndrome, condition in which cardiorespiratory failure occurs during an hypoxic episode, as sleep apnea. Pregnant rats were given nicotine infusions of 2 or 6 mg/kg/day throughout gestation, regimens that produce plasma levels spanning the range smokers. The day after birth, animals dose group displayed excessive mortality challenge. These found to be deficient essential response component, namely adrenomedullary catecholamine release is required maintain neonatal cardiac rhythm hypoxia; defect was adrenal cell function rather than altered innervation nicotinic receptor desensitization. We also examined brainstem and forebrain noradrenergic mechanisms are involved respiratory control. showed suppressed spontaneous neuronal activity, but hyperresponsive hypoxia. As these projections inhibitory for respiration, nicotine-induced sensitization would expected contribute arrest Prenatal exposure may thus provide useful animal model study physiological underlie Sudden while at same time providing biological explanation association syndrome smoking.