Fig. 3.

Time course of MTII-induced ERK1/2 phosphorylation in hindbrain following fourth ventricle MTII injection. Schematic depicts the level of the hindbrain at which representative immunofluorescent images were captured. Immunofluorescent images represent the time course for the appearance of pERK1/2 immunoreactivity in the NTS and dorsal motor nucleus of the vagus (DMV) following fourth ventricle injection of MTII (50 pmol) in overnight-fasted rats. Graphs in the lower panel are quantification of pERK1/2-immunoreactive neurons in the NTS (commissural and medial) and DMV represented as averages for each time period, counted from coronal sections at four rostrocaudal levels of the hindbrain. AP, area postrema; DMV, dorsal motor nucleus of the vagus; NTS, nucleus of the solitary tract. *Significantly different (P ≤ 0.05) from saline control treatment.