Striatal dopamine D1 receptor is essential for contextual fear conditioning.
Fear memory is critical for animals to trigger behavioural adaptive responses to potentially threatening stimuli, while too much or inappropriate fear may cause psychiatric problems. Numerous studies have shown that the amygdala, hippocampus and medial prefrontal cortex play important roles in Pavlovian fear conditioning. Recently, we showed that striatal neurons are required for the formation of the auditory fear memory when the unconditioned stimulus is weak. Here, we found that selective ablation of striatal neurons strongly diminished contextual fear conditioning irrespective of the intensity of footshock. Furthermore, contextual fear conditioning was strongly reduced in striatum-specific dopamine D1 receptor knockout mice. On the other hand, striatum-specific dopamine D2 receptor knockout mice showed freezing responses comparable to those of control mice. These results suggest that striatal D1 receptor is essential for contextual fear conditioning.
Department of Molecular Neurobiology and Pharmacology, Graduate School of Medicine, University of Tokyo, Tokyo, Japan.
Masaru
M
Ikegami
1] Department of Molecular Neurobiology and Pharmacology, Graduate School of Medicine, University of Tokyo, Tokyo, Japan [2] Department of Molecular and Cellular Physiology, Shinshu University School of Medicine, Nagano, Japan.
Takeshi
T
Uemura
Department of Molecular Neurobiology and Pharmacology, Graduate School of Medicine, University of Tokyo, Tokyo, Japan.
Ayumi
A
Kishioka
Department of Cellular Neurobiology, Brain Research Institute, Niigata University, Niigata, Japan.
Kenji
K
Sakimura
1] Department of Molecular Neurobiology and Pharmacology, Graduate School of Medicine, University of Tokyo, Tokyo, Japan [2] Brain Science Laboratory, The Research Organization of Science and Technology, Ritsumeikan University, Kusatsu, Shiga, Japan.
Masayoshi
M
Mishina
D000679:Amygdala / Q000502:physiology; D000818:Animals; D003214:Conditioning, Classical / Q000502:physiology*; D003342:Corpus Striatum / Q000378:metabolism; D005239:Fear / Q000502:physiology* / Q000523:psychology; D006624:Hippocampus / Q000502:physiology; D008568:Memory / Q000502:physiology*; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D017397:Prefrontal Cortex / Q000502:physiology; D017447:Receptors, Dopamine D1 / Q000235:genetics*; D017448:Receptors, Dopamine D2 / Q000235:genetics*
D017447:Receptors, Dopamine D1; D017448:Receptors, Dopamine D2