Faculty Collaboration Database

Synaptic relationship between somatostatin- and neurokinin-1 receptor-immunoreactive neurons in the pre-Bötzinger complex of rats. J Neurochem 2012 Sep;122(5):923-33

Date

07/07/2012

Pubmed ID

22765158

DOI

10.1111/j.1471-4159.2012.07862.x

Scopus ID

2-s2.0-84865323055 (requires institutional sign-in at Scopus site)   19 Citations

Abstract

The pre-Bötzinger complex (pre-BötC) in the ventrolateral medulla oblongata is critical for the generation of respiratory rhythm in mammals. Somatostatin (SST) and neurokinin 1 receptor (NK1R) immunoreactivity have been used as markers of the pre-BötC. SST immunoreactivity almost completely overlaps with small fusiform NK1R-immunoreactive (ir) neurons, the presumed rhythmogenic neurons, but not with large multipolar NK1R-ir neurons. Understanding the neurochemical characteristics, especially the synaptic relationship of SST/NK1R-ir neurons within the pre-BötC network is essential in providing cellular and structural bases for understanding their physiological significance. This work has not been documented so far. We found that SST immunoreactivity was highly expressed in terminals, somas, and primary dendrites in the pre-BötC. Besides the small fusiform neurons, a small population of medium-sized NK1R-ir neurons also colocalized with SST. Large NK1R-ir neurons were not SST-ir, but received somatostatinergic inputs. SST-ir terminals were glutamatergic or GABAergic, and synapsed with NK1R-ir neurons. Most of synapses between them were of the symmetric type, indicating their inhibitory nature. Asymmetric synapses were evident between SST-ir terminals and NK1R-ir dendrites, strongly suggesting an excitatory innervation from the presumed rhythmogenic neurons as these neurons are glutamatergic. We speculate that SST-mediated excitatory and inhibitory synaptic transmission onto NK1R-ir rhythmogenic and follower neurons synchronizes their activity to contribute to respiratory rhythmogenesis and control.

Author List

Wei XY, Zhao Y, Wong-Riley MT, Ju G, Liu YY

Author

Margaret Wong-Riley PhD, MA Emeritus Professor in the Cell Biology Neurobiology and Anatomy department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Animals
Glutamate Decarboxylase
Glycine Plasma Membrane Transport Proteins
Male
Microscopy, Immunoelectron
Neurons
Rats
Rats, Sprague-Dawley
Receptors, Neurokinin-1
Respiratory Center
Somatostatin
Synapses
Ultrasonography
Vesicular Glutamate Transport Protein 2