Postnatal developmental expressions of neurotransmitters and receptors in various brain stem nuclei of rats. J Appl Physiol (1985) 2005 Apr;98(4):1442-57
Date
12/25/2004Pubmed ID
15618314DOI
10.1152/japplphysiol.01301.2004Scopus ID
2-s2.0-15444362711 (requires institutional sign-in at Scopus site) 80 CitationsAbstract
Previously, we reported that the expression of cytochrome oxidase in a number of brain stem nuclei exhibited a plateau or reduction at postnatal day (P) 3-4 and a dramatic decrease at P12, against a general increase with age. The present study examined the expression of glutamate, N-methyl-D-aspartate receptor subunit 1 (NMDAR1), GABA, GABAB receptors, glycine receptors, and glutamate receptor subunit 2 (GluR2) in the ventrolateral subnucleus of the solitary tract nucleus, nucleus ambiguus, hypoglossal nucleus, medial accessory olivary nucleus, dorsal motor nucleus of the vagus, and cuneate nucleus, from P2 to P21 in rats. Results showed that 1) the expression of glutamate increased with age in a majority of the nuclei, whereas that of NMDAR1 showed heterogeneity among the nuclei; 2) GABA and GABAB expressions decreased with age, whereas that of glycine receptors increased with age; 3) GluR2 showed two peaks, at P3-4 and P12; and 4) glutamate and NMDAR1 showed a significant reduction, whereas GABA, GABAB receptors, glycine receptors, and GluR2 exhibited a concomitant increase at P12. These features were present but less pronounced in hypoglossal nucleus and dorsal motor nucleus of the vagus and were absent in the cuneate nucleus. These data suggest that brain stem nuclei, directly or indirectly related to respiratory control, share a common developmental trend with the pre-Botzinger complex in having a transient period of imbalance between inhibitory and excitatory drives at P12. During this critical period, the respiratory system may be more vulnerable to excessive exogenous stressors.
Author List
Liu Q, Wong-Riley MTMESH terms used to index this publication - Major topics in bold
AgingAnimals
Animals, Newborn
Brain Stem
Gene Expression Regulation, Developmental
Glutamic Acid
Neurotransmitter Agents
Rats
Rats, Sprague-Dawley
Receptors, AMPA
Receptors, GABA-B
Receptors, Glycine
Receptors, N-Methyl-D-Aspartate
Sensory Receptor Cells
Tissue Distribution
gamma-Aminobutyric Acid