» Articles » PMID: 31828746

Inhibition of NR2B-containing NMDA Receptors During Nitrogen Narcosis

Overview
Date 2019 Dec 13
PMID 31828746
Citations 1
Authors
Affiliations
Soon will be listed here.
Abstract

Introduction: When humans breathe compressed air or N-O mixtures at three to four atmospheres pressure, they will experience nitrogen narcosis that may possibly lead to a diving accident, but the underlying mechanisms remain unclear.

Methods: Mice were exposed to 1.6 MPa breathing a N-O mixture adjusted to deliver an inspired PO of 32-42 kPa. The electroencephalogram (EEG) and forced swimming test were used to evaluate the narcotic effect of nitrogen. Neuronal activity was observed via c-Fos expression in cortex and hippocampus tissue after decompressing to the surface. To further investigate underlying molecular mechanisms, we incubated cultured hippocampal neurons with various NMDA concentrations, and measured expression of NMDA receptors and its down-stream signal with or without 1.6 MPa N-O exposure.

Results: Both the frequency of the EEG and the drowning time using the forced swimming test were significantly decreased during exposure to 1.6 MPa N-O (P < 0.001). Additionally, in cultured hippocampal neurons, the increased levels of phosphorylated NR2B and cAMP-response element binding protein (CREB) induced by NMDA stimulation were significantly inhibited by exposure to 1.6 MPa N-O.

Conclusions: Our findings indicated that NR2B-containing NMDA receptors were inhibited during nitrogen narcosis.

Citing Articles

Anterior Cingulate Cortex Contributes to the Hyperlocomotion under Nitrogen Narcosis.

Peng B, Wu X, Zhang Z, Cao D, Zhao L, Wu H Neurosci Bull. 2024; .

PMID: 39158823 DOI: 10.1007/s12264-024-01278-z.

References
1.
Nakanishi S . Molecular diversity of glutamate receptors and implications for brain function. Science. 1992; 258(5082):597-603. DOI: 10.1126/science.1329206. View

2.
Vallee N, Rostain J, Risso J . How can an inert gas counterbalance a NMDA-induced glutamate release?. J Appl Physiol (1985). 2009; 107(6):1951-8. DOI: 10.1152/japplphysiol.00097.2009. View

3.
Kratzer S, Mattusch C, Kochs E, Eder M, Haseneder R, Rammes G . Xenon attenuates hippocampal long-term potentiation by diminishing synaptic and extrasynaptic N-methyl-D-aspartate receptor currents. Anesthesiology. 2012; 116(3):673-82. DOI: 10.1097/ALN.0b013e3182475d66. View

4.
Lavoute C, Weiss M, Risso J, Rostain J . Mechanism of action of nitrogen pressure in controlling striatal dopamine level of freely moving rats is changed by recurrent exposures to nitrogen narcosis. Neurochem Res. 2011; 37(3):655-64. DOI: 10.1007/s11064-011-0657-1. View

5.
Chung H, Huang Y, Lau L, Huganir R . Regulation of the NMDA receptor complex and trafficking by activity-dependent phosphorylation of the NR2B subunit PDZ ligand. J Neurosci. 2004; 24(45):10248-59. PMC: 6730169. DOI: 10.1523/JNEUROSCI.0546-04.2004. View