Bilateral terminal fibers, connected to the paratrigeminal core was also observed in solitary tract nucleus, lateral reticular nucleus (LRT), ambiguous nucleus (Amb), rostroventrolateral reticular nucleus (RVL), beeing the vegetative actions explained by its projections (de Sousa Buck et al.; Caous et al., 2008).
Among the nuclei of the ventral medulla, for whom PA5 projections, the RVL is the most involved with the control of vasomotor tone (Caous et al., 2001).
As well as being interrelated to vegetative activity and motor coordination of talking and deglution, it has also been attributed with regulating blood-pressure, controlling visceral pain, thermal regulation and motivational-affective responses to pain due to its connections with the solitary nucleus, raphe magnus, parabrachial area and amygdaloid nucleus (trigeminal-parabrachial-amygdaloid ipsilateral tract) with its usual visceral, nutritional (anorexia), respiratory, thermal and inhibitory descending pain effects (Caous et al.; Armstrong & Holpkins; Jasmin et al., 1997; Paues et al., 2006; Rybka & McCulloch, 2006).
These afferents reach this nucleus' neuropil, overlapping it (without interneurons) and making a connection with structures related to autonomous control of the pons and medulla oblongata, but also directing themselves towards SC5, thereby interrelating themselves with trigeminal dynamics of pain in the head and neck (Caous et al.; Bon et al.; Saxon & Holpkins, 1998, 2006; Armstrong & Hopkins; Lindsey et al., 1997; Lapa & Watanabe, 2005).