Figure 5: Potential brain nuclei of which neurons respond to intracisternal injection of amino acid solution, in the sagittal view of the rat brain. SON, the supraoptic nucleus of the hypothalamus; NTS, the nucleus tractus solitarii; RVLM, rostral ventrolateral medulla; CVLM, caudal ventrolateral medulla; CPA, caudal pressor area. Gray area indicates the ventricular system from the third ventricle to the central canal in the spinal cord.