Dendritic length of hippocampal neurons. Extending melatonin exposure duration reduces total and apical dendritic length of pyramidal neurons in CA1 (D). Extending melatonin increases total dendritic length of the CA3 neurons, mainly in the basilar dendrites (E). Shared letters indicate no significant differences LSD post-hoc test. Data in D, E, and F are collapsed by melatonin exposure duration from A, B, and C respectively. A, B, and C share key depicted in C. D, E, and F share key depicted in F. *p < 0.05 Student's t test