Fig. 6.

Representative images of hindbrain Fos expression in the reticular formation (oval areas) at the level of the AP (+250 μm rostral to obex, see Fig. 2) 6 h after intraperitoneal injection with saline, cisplatin (30 mg/kg), or cisplatin + palonosetron (0.5 mg/kg). Palonosetron, a serotonin type 3 (5-HT₃) receptor antagonist, was injected 15 min before injection with cisplatin. Images show only one half of the hindbrain, and Fos expression in the reticular formation was present on both sides. The lower 1/3 of the region of interest likely includes the nucleus ambiguous and C1/A1.