Fig. 1

BDA injection sites. a & b Camera lucida drawings from saggital brainstem sections that contain a BDA deposit in the parabrachial nucleus (a & b). c-g Microphotographs of a BDA injection site are shown in low-power (c: Nova Red; d: Nissl-stained) and magnified views (e & h: Nova Red; f & g: Nissl-stained) The nomenclature for the divisions of subdivisions of the parabrachial nucleus was adapted from Sarhan et al. [21]. Note that the injection site is centered in the central lateral (cl) subnuclus of the parabrachial nucleus. cl, central lateral subnucleus; dl, dorsal lateral subnucleus; el, external lateral subnucleus; em, external medial subnucleus; lcr, lateral crescent subnucleus; ll, lateral lemniscus; LPB, lateral parabrachial nucleus; m, medial parabrachial nucleus; mel, external lateral subnucleus of the mesencephalic parabrachial nucleus; Mo5, trigeminal motor nucleus; scp, superior cerebellar peduncle; scpd, superior cerebellar peduncle, descending limb; sl, superior lateral subnucleus of the mesencephalic parabrachial nucleus; vl, ventral lateral subnucleus; vsc, ventral spinocerebellar tract; 7n, facial nerve; 7, facial nucleus. Scale bar = 500 μm (a-d), 150 μm (e-h)