Getting rid of a protein increases the birth of new nerve cells and shortens the time it takes for antidepressants to take effect, according to an animal study in the March 7 issue of The Journal of Neuroscience. The protein, neurofibromin 1, normally helps prevent uncontrolled cell growth. The findings suggest therapeutic strategies aimed at stimulating new nerve cell birth may help treat depression better than current antidepressants that commonly take several weeks to reach full efficacy.