Figure 1.
Photomicrographs illustrating the rostrocaudal levels and subdivisions of the dorsal raphe nucleus sampled for analysis of immunohistochemical staining. Dashed lines delineate each subdivision. Numbers in the lower left of each panel indicate the distance from bregma, based on a standard stereotaxic atlas of the rat brain (Paxinos and Watson, 1998). (A) −7.46 mm bregma, (B) −8.00 mm bregma, (C) −8.18 mm bregma, and (D) −8.54 mm bregma. Abbreviations: Aq, cerebral aqueduct; bv, blood vessel; DRC, dorsal raphe nucleus, caudal part; DRD, dorsal raphe nucleus, dorsal part; DRI, dorsal raphe nucleus, interfascicular part; DRV, dorsal raphe nucleus, ventral part; DRVL/VLPAG, dorsal raphe nucleus, ventrolateral part/ventrolateral periaqueductal gray; mlf, medial longitudinal fasciculus. Scale bar, 250 μm.