The hindbrain parabrachial complex (PBc) is a sensory relay in the CNS. The forebrain extended amygdala (EA) orchestrates adaptive responses to emotional events. While PBc-EA connection has been extensively studied, cell type specificity and types of synapses remained unclear.  In order to address these questions we used a systematic anatomical analysis (immunohistochemistry IHC and double in situ hybridization, DISH) of neuropeptides PACAP, CGRP and neurotensin-NT distribution in rat N=20 and mice N=20 brains, we observed perisomatic ring-like structures containing the three peptides as well as VGLUT1/VGLUT2 in the EA. The origin of those structures was studied using in vivo juxtacellular labeling and tracing study using Adcyap1-Cre for Cre-dependent expression of fluorescent marker fused with artificial channelrhodopsin. PACAP/CGRP/NT/ VGLUT1/VGLUT2 expression was a molecular signature of the pre-synaptic neurons from the posterior-ventral division of PBc.  PKCdelta-GABAergic neurons in the EA, co-expressing Adcyap1r1 and Vipr1 mRNA were identified as the post-synaptic cells. This signature, except co-expressing PKCdelta is characteristic of the Calyx-of-Held, a rare perisomatic large glutamatergic synapse in brainstem' medial nucleus of the trapezoid body (MNTB), which receive axons from globular bushy neurons in the ventral cochlear nucleus. Using transmission electron microscopy (TEM) and focused ion beam scanning electron microscopy (FIBSEM), in combination with immunohistochemistry, we demonstrated that the ring-structures in EA are highly similar to the Calyx-of-Held observed in the MNTB. Taken together, our results suggest a common molecular basis for calyceal synaptogenesis both in hindbrain and forebrain. The PBc–>EA Calyx-of-Held synapse may represent a previously unappreciated morphological substrate for high fidelity sensory alert to the forebrain center for adaptive response. This study was performed in accordance with the recommendations in the Guide for the Care and Use of Laboratory Animals of the National Institutes of Health. All experiments were approved by the NIMH Institutional Animal Care and Use Committee (ACUC, LCMR-08) and the Research and Ethics Committee of the Faculty of Medicine, Universidad Nacional Autónoma de México (CIEFM 062/2016).