Gamma‐aminobutyric acid (GABA) is a prominent inhibitory transmitter in both the central nucleus of the amygdala (Ce) and the medial nuclei of the solitary tracts (mNTS). These regions are reciprocally connected by anatomical pathways mediating the coordinated visceral responses to emotional stress. To further determine whether GABA is present in the amygdaloid efferents or their targets in the mNTS, we combined peroxidase labeling of Phaseolus vulgaris leucoagglutinin (PHA‐L) or biotinylated dextran amine (BDA) anterogradely transported from the Ce with immunogold‐silver detection of antibodies against GABA in the rat mNTS. By light microscopy, peroxidase labeling for either PHA‐L or BDA was seen in varicose processes, whereas immunogold‐silver labeling for GABA was detected in perikarya and processes throughout the rostrocaudal mNTS. The intermediate mNTS at the level of the area postrema, a region receiving mainly cardiorespiratory and gastric visceral afferents, were examined by electron microscopy. In this region, anterograde labeling was observed exclusively in unmyelinated axons and axon terminals. These terminals lacked detectable GABA‐immunoreactivity, but formed symmetric synapses that are associated with inhibition. The targets of the anterogradely labeled terminals were medium‐sized dendrites both with and without GABA‐labeling. These dendrites often also received convergent input from terminals that were intensely GABA‐immunoreactive. We conclude that visceral activation accompanying emotional response to stress is likely to involve inhibition of GABAergic neurons in the mNTS by non‐GABA‐containing amygdaloid efferents. Furthermore, our results indicate that the inhibition of these GABAergic neurons may be further augmented by release of GABA from other converging terminals in the mNTS. © 1996 Wiley‐Liss, Inc.
Journal of Neuroscience Research – Wiley
Published: Jun 1, 1996
It’s your single place to instantly
discover and read the research
that matters to you.
Enjoy affordable access to
over 18 million articles from more than
15,000 peer-reviewed journals.
All for just $49/month
Query the DeepDyve database, plus search all of PubMed and Google Scholar seamlessly
Save any article or search result from DeepDyve, PubMed, and Google Scholar... all in one place.
Get unlimited, online access to over 18 million full-text articles from more than 15,000 scientific journals.
Read from thousands of the leading scholarly journals from SpringerNature, Wiley-Blackwell, Oxford University Press and more.
All the latest content is available, no embargo periods.
“Hi guys, I cannot tell you how much I love this resource. Incredible. I really believe you've hit the nail on the head with this site in regards to solving the research-purchase issue.”Daniel C.
“Whoa! It’s like Spotify but for academic articles.”@Phil_Robichaud
“I must say, @deepdyve is a fabulous solution to the independent researcher's problem of #access to #information.”@deepthiw
“My last article couldn't be possible without the platform @deepdyve that makes journal papers cheaper.”@JoseServera