HEALTH Q and A

A molecular mechanism in the brain that explains how nicotine alters moods and heightens alertness has been found. Neurobiologists said this mechanism is triggered by nicotine in levels normally found in smokers.

They also said that nicotine causes the brain’s nerve cells to send out a larger-than-normal amount of a substance called glutamate. Glutamate is the key central nervous system excitory transmitter, which means it excites the cells. Researchers said that the large amount of glutamate explains why nicotine can heighten alertness and improve short-term- memory. These findings, they said, may contribute to development of treatments for people addicted to nicotine.