Enhancement of GluN2B Subunit-Containing NMDA Receptor Underlies Serotonergic Regulation of Long-Term Potentiation after Critical Period in the Rat Visual Cortex.
10.4196/kjpp.2015.19.6.523
- Author:
Kayoung JOO
1
;
Duck Joo RHIE
;
Hyun Jong JANG
Author Information
1. Department of Physiology, College of Medicine, The Catholic University of Korea, Seoul 06591, Korea. hjjang@catholic.ac.kr
- Publication Type:Original Article
- Keywords:
5-HT;
AMPA receptor;
GABA(A) receptor;
Metaplasticity;
Serotonin
- MeSH:
Animals;
Critical Period (Psychology)*;
Humans;
Long-Term Potentiation*;
N-Methylaspartate*;
Plastics;
Rats*;
Receptors, AMPA;
Receptors, GABA;
Receptors, GABA-A;
Serotonin;
Synaptic Transmission;
Visual Cortex*
- From:The Korean Journal of Physiology and Pharmacology
2015;19(6):523-531
- CountryRepublic of Korea
- Language:English
-
Abstract:
Serotonin [5-hydroxytryptamine (5-HT)] regulates synaptic plasticity in the visual cortex. Although the effects of 5-HT on plasticity showed huge diversity depending on the ages of animals and species, it has been unclear how 5-HT can show such diverse effects. In the rat visual cortex, 5-HT suppressed long-term potentiation (LTP) at 5 weeks but enhanced LTP at 8 weeks. We speculated that this difference may originate from differential regulation of neurotransmission by 5-HT between the age groups. Thus, we investigated the effects of 5-HT on apha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR)-, gamma-aminobutyric acid receptor type A (GABA(A)R)-, and N-methyl-D-aspartic acid receptor (NMDAR)-mediated neurotransmissions and their involvement in the differential regulation of plasticity between 5 and 8 weeks. AMPAR-mediated currents were not affected by 5-HT at both 5 and 8 weeks. GABA(A)R-mediated currents were enhanced by 5-HT at both age groups. However, 5-HT enhanced NMDAR-mediated currents only at 8 weeks. The enhancement of NMDAR-mediated currents appeared to be mediated by the enhanced function of GluN2B subunit-containing NMDAR. The enhanced GABA(A)R- and NMDAR-mediated neurotransmissions were responsible for the suppression of LTP at 5 weeks and the facilitation of LTP at 8 weeks, respectively. These results indicate that the effects of 5-HT on neurotransmission change with development, and the changes may underlie the differential regulation of synaptic plasticity between different age groups. Thus, the developmental changes in 5-HT function should be carefully considered while investigating the 5-HT-mediated metaplastic control of the cortical network.
