Figure 1.

Leydig cells in postnatal rat testis possess GAD, VGAT and GABA_A-α1. Immunohistochemical localization of GAD, VGAT and GABA_A-α1 in the testis of five days old rats. Fetal Leydig cells with typical rounded morphology are located in clusters between the seminiferous tubules and are immunopositive for GAD (A) and VGAT (B). No reaction was observed in sections incubated with buffer (data not shown) or non-immune rabbit serum (C) instead of the primary antibody. The GABA_A receptor subunit α1 (D) is also immunolocalized to clustered fetal Leydig cells (*). However other interstitial cells with a spindle-shaped appearance also exhibit specific immunoreactivity against GABA_A-α1 (D, →). The insert panel (D) also depicts magnified spindle-shaped interstitial cells of another section, which are immunopositive for GABA_A-α1. No reaction was observed in sections incubated with buffer (data not shown) or non-immune rabbit serum (E) instead of the primary antibody. Bars: 50 μm.