Figure 6 - Map of deglutitive response loci in the rat NTS as determined by pressure pulse microejection of L-glutamate or excitatory amino acid agonists.

Sites included in this analysis typically yield stable highly reproducible responses with repeated stimulation and are distinctly localized. In the rostrocaudal series of transverse sections through the NTS, the distance from the obex is indicated in micrometers (m). The shaded region outlines the caudal dense portion of the central subnucleus.

Representative examples of swallowing response types (below, left to right) elicited by glutamate chemomicrostimulation (downward blue arrowheads). Manometric traces show intraluminal pressure signals recorded from pharynx (P), cervical esophagus (CE), and distal esophagus (DE), along with intratracheal pressure (R) or respiratory rate (RR). () An isolated propagated pressure wave in esophagus evoked from midportion of central subnucleus. () Nonpropagated pharyngeal response evoked from NTS_im/v region. (^*) A complete swallow sequence triggered from site in ventral NTS_im (all traces courtesy of M.A. Hashim). (Source: Adapted from Bieger,⁸ with permission from Springer Science and Business Media.)