FIGURE 9.

Examples of retrograde axonal labeling (CTB) resulting from unilateral tracer injections in the LPO (#181221‐04A) and LHAa (#181221‐02A). (a and b) Very abundant ipsilateral retrograde labeling from LPO (a) and LHAa (b) in the lateral septal nucleus rostral (LSr) and caudal (LSc) parts; substantial (but far less abundant) retrograde labeling was also present at this level in the contralateral LSr from the LHAa (b, and outset), and a prominent cluster of contralateral retrograde labeling from the LPO (a, and outset) is visible in the median preoptic nucleus (MEPO). (c and d) Retrograde labeling in the vicinity of the posterior hypothalamus (PH), with noticeably more contralateral labeling from the LHAa (d, and outset) than LPO (c, and outset). Also at this posterior hypothalamic level, strong anterograde labeling is present in an LHA region corresponding to the rat LHA posterior region (LHAp). Dashed lines indicate approximate cytoarchitectural boundaries corresponding to reference atlas parcellation. Additional abbreviations: aco, anterior commissure (olfactory limb); cc, corpus callosum; fx, fornix; LSv, lateral septal nucleus ventral part; mtt, mammillothalamic tract; PMd, dorsal premammillary nucleus; PMv, ventral premammillary nucleus; PVp, periventricular hypothalamic nucleus posterior part; V3, third ventricle; VL, lateral ventricle. Scale bars are 500 μm