HELSINKI, Finland, March 22 (UPI) -- Children born to women who smoked during pregnancy have an increased risk of smoking, due to prenatal nicotine exposure, researchers in Finland and Russia say.
Researchers conducting a joint Finnish-Russian project of the University of Helsinki, the Saint Petersburg Pavlov Medical University in Russia and Shemyakin-Ovchinnikov Institute of Bio-organic Chemistry in Moscow, say their findings support the hypothesis that teens with prenatal nicotine exposure are more likely to start smoking earlier than their peers.
The researchers examined the receptor-level combined effects of opioids -- morphine and morphine-related compounds -- and nicotine.
Principal investigator Raimo K. Tuominen of the University of Helsinki says receptor is a human protein to which compounds bind and once the receptors are activated, they trigger a number of intracellular signals.
The study used cell lines that express different subtypes of nicotinic receptors -- nicotine attaches to these receptors and activates them.
The findings show morphine and its related compounds, which normally attach to their own receptors, also bind to nicotinic receptors -- causing altered nicotine responses.
The findings are published in the European Journal of Pharmacology.