Effects of the alpha- and gamma-polymorphs of glycine on the behavior of catalepsy prone rats

► α- and γ-polymorphs of glycine have different effects on the behavior of GC rats. ► Only the γ-polymorph decreases the duration of catalepsy and anxiety in elevated plus-maze. ► Both glycine polymorphs increase exploratory behaviors. ► The γ-polymorph has a more beneficial effect.