Pathological data on apoptosis in the brainstem and physiological data on sleep apnea in SIDS victims

Department of Legal Medicine, Tokyo Women's Medical University School of Medicine, 8-1 Kawada-cho, Shinjuku, Tokyo 162-8666, Japan.
Early Human Development (Impact Factor: 1.93). 06/2004; 75 Suppl:S13-20. DOI: 10.1016/j.pathophys.2004.01.003
Source: PubMed

ABSTRACT The sudden infant death syndrome (SIDS) is still the main cause of postneonatal infant death and its cause is still unknown. A chronic hypoxic situation has been shown to exist in the brains of SIDS victims and apoptosis has been demonstrated in hypoxic situations. In this study, the correlation between apoptotic neurons or glias and sleep apnea in SIDS was investigated in the brainstem of SIDS victims.
In a cohort of 27,000 infants studied prospectively to characterize their sleep-wake behavior, 38 infants died under 6 months of age. They included 26 cases of SIDS. The frequency and duration of sleep apnea were analyzed. The brainstem material was collected and terminal-deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) method was carried out. The density of TUNEL-positive neurons or glias was measured quantitatively. Correlation analyses were carried out between the apoptosis-associated pathological data and the physiological data of sleep apnea.
No significant negative or positive correlation between the density of TUNEL-positive neurons or glias and the characteristics of sleep apnea was observed in SIDS victims. No statistically significant differences associated with apoptotic neurons and glias were observed between SIDS and non-SIDS.
The pathological findings of apoptosis were not in agreement with the hypothesis refer to apnea and arousal phenomenon in pathophysiology of SIDS.

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