A new study has identified a specific class of pharmaceutical drugs that could be effective in treating babies vulnerable to Sudden Infant Death Syndrome (SIDS), because their mothers smoked during pregnancy.
According to researchers at McMaster University, exposure of the fetus to nicotine results in the inability to respond to decreases in oxygenknown as hypoxiawhich may result in a higher incidence of SIDS. In the same study on rats, they found that the diabetic medication 'glibenclamide' can reverse the effects of nicotine exposure, increasing the newborn's ability to respond to hypoxia and likely reducing the incidence of SIDS.
The findings are published today in the Journal of Neuroscience.
"During birth the baby rapidly changes its physiology and anatomy so that it can breathe on its own," explains Josef Buttigieg, lead author who conducted his research as a PhD graduate student in the department of Biology. "The stress of being born induces the release of the hormones adrenaline and noradrenalinecollectively called catecholaminesfrom the adrenal glands. During birth, these hormones in turn signal the baby's lungs to become ready for air breathing."
For some months after birth, the adrenal glands act as a critical oxygen sensor. A drop in blood oxygen levels will stimulate the release of catecholamines, which in turn signals the baby to take a deep breath, when an infant rolls on its face or has an irregular breathing pattern during sleep, for example. However, the ability to release those hormones during moments of apnea or asphyxia is impaired due to nicotine exposure.
During those episodes, specific proteins sensitive to hypoxia stimulate the cell to release catecholamines. A secondary class of proteins then acts as a 'brake', ensuring the cells do not over excite themselves during this stressful time. However, exposure of the fetus to nicotine results in higher levels of this brake prote
|Contact: Michelle Donovan|