Intensity of blue or red boxes represent the extremes of the Rho (ρ) coefficient of +1.0 to −1.0, respectively, as showed in grading bar on the right. *, p ≤ 0.10; **, p ≤ 0.05; ***, p ≤ 0.01. Sexual dimorphism shown in the relationship of PNN volume vs. number of NPTX2+ puncta per 102 μm of PV IN surface area in the CA1. CA, cornus ammonis; IF, immunofluorescence; NPTX2, neuronal pentraxin 2; P, post-natal age; PNN, perineural nets; PV, parvalbumin; SA, surface area; WFA, Wisteria floribunda lectin.