Figure 2.

Caudal to rostral distribution of retrogradely traced neurons in the guinea pig nucleus ambiguus (nAmb). Neurons were traced by administering 2% DiI (A) unilaterally to the mid cervical recurrent laryngeal nerve (RLN), (B) unilaterally to the RLN at its termination at the base of the larynx (C) to the tracheal adventitia or (D) to the cervical esophageal muscle layers. The distribution co-ordinates show the caudal (negative) and rostral (positive) location relative to the Obex (0). Note, in (A,B), no traced neurons were identified in the contralateral nAmb. Data are the mean ± sem of 3–4 experiments. See text for further details.