CHRM1 and major depressive disorder: The hypotheses that can be built from these observations are: i) the functionality of M1R implicates directly in dopamine release (23); ii) dopaminergic activity contributes to attenuate anxiety – probably by dopaminergic receptor subtype 2 – and depression; iii) Bj-PRO-7a would increase dopamine transmission on mesolimbic and mesocortical systems related to anxiolysis, motivation, exploration, and antidepressant effects (30).