Skip to content

Brain-derived neurotrophic factor Val66Met allele impairs basal and ketamine-stimulated synaptogenesis in prefrontal cortex.

Rong-Jian Liu, Francis S Lee, Xiao-Yuan Li, Francis Bambico, Ronald S. Duman, George K. Aghajanian

Biological Psychiatry June 1, 2012 DOI: 10.1016/j.biopsych.2011.09.030 (opens in new tab)

Study at a glance

AI-extracted from the abstract
Characteristics Animal study (knock-in mouse model, ex vivo electrophysiology and behavioral experiments) Peer reviewed
Population Knock-in mice expressing the human BDNF Val66Met polymorphism (wildtype, Val/Met, and Met/Met genotypes)
Intervention Ketamine
Dose a low dose of ketamine
Measures Whole-cell recordings, two-photon laser scanning, forced swim test
Topics Esketamine Ketamine
Key findings Met allele mice showed constitutive atrophy of distal apical dendrites, reduced apically targeted excitatory postsynaptic currents, and decreased spine density and diameter in layer V prefrontal pyramidal cells. In Met/Met mice, ketamine's synaptogenic effect was markedly impaired and its antidepressant response in the forced swim test was blocked. The authors conclude that the Met allele produces basal synaptic deficits and blocks ketamine's synaptogenic and antidepressant actions.

Abstract

Knock-in mice with the common human brain-derived neurotrophic factor (BDNF) Val66Met polymorphism have impaired trafficking of BDNF messenger RNA to dendrites. It was hypothesized, given evidence that local synapse formation is dependent on dendritic translation of BDNF messenger RNA, that loss-of-function Met allele mice would show synaptic deficits both at baseline and in response to ketamine, an N-methyl-D-aspartate antagonist that stimulates synaptogenesis in prefrontal cortex (PFC). Whole-cell recordings from layer V medial PFC pyramidal cells in brain slices were combined with two-photon laser scanning for analysis of wildtype, Val/Met, and Met/Met mice both at baseline and in response to a low dose of ketamine. Val/Met and Met/Met mice were found to have constitutive atrophy of distal apical dendrites and decrements in apically targeted excitatory postsynaptic currents in layer V pyramidal cells of PFC. In addition, spine density and diameter were decreased, indicative of impaired synaptic formation/maturation (synaptogenesis). In Met/Met mice the synaptogenic effect of ketamine was markedly impaired, consistent with the idea that synaptogenesis is dependent on dendritic translation/release of BDNF. In parallel behavioral studies, we found that the antidepressant response to ketamine in the forced swim test was blocked in Met/Met mice. The results demonstrate that expression of the BDNF Met allele in mice results in basal synaptic deficits and blocks synaptogenic and antidepressant actions of ketamine in PFC, suggesting that the therapeutic response to this drug might be attenuated or blocked in depressed patients who carry the loss of function Met allele.

Comparable studies

Other preclinical and animal studies on ketamine, most cited first.

Citations in the library

Cited by 118

and 113 more in the library

Cites 8

and 3 more in the library

Explore topics