Poster

Poster 18 Memory, Emotion, Behavior 2 ポスター 18 記憶、情動、行動2

P18-1 Effect of acute atomoxetine on brain activity in medial prefrontal cortex during reward task: an fMRI study 報酬課題における内側前頭前野の脳活動に対するアトモキセチンの効果：機能的MRIによる検討 Suzuki Chihiro（鈴木千裕）¹，池田裕美子²，舘野周³，大久保善朗³，深山治久¹，鈴木秀典² ¹Anesthesiology and Clinical Physiology, Tokyo Medical and Dental University, Tokyo, Japan ²日本医科大学　薬理学 ³日本医科大学　精神医学 Atomoxetine, a noradrenaline reuptake inhibitor, has been widely used as a non-stimulant medication for attention deficit hyperactivity disorder (ADHD). Animal studies have shown that atomoxetine increases extracellular levels of both noradrenaline and dopamine in prefrontal cortex (PFC), which is a critical region in mesocorticolimbic pathway involved in reward processing. Although it has been thought that the dysfunction of reward system is at least partly responsible for the symptoms in patients with ADHD, there have been few studies regarding the effects of atomoxetine on the reward system. Therefore, we investigated whether a single dose of atomoxetine affects reward processing in healthy adults using functional magnetic resonance imaging (fMRI). A randomized, double-blind, placebo-controlled, crossover study was conducted for fourteen healthy adults under atomoxetine or placebo. We adopted the monetary incentive delay task, which can assess neural responses to monetary reward anticipation in the nucleus accumbens (NAc) and outcome in the medial prefrontal cortex (MPFC), respectively. The study was approved by the ethics committee of the Nippon Medical School. Blood oxygenation level-dependent (BOLD) signals in MPFC showed a significant decrease during gain outcome under atomoxetine compared with placebo. In gain anticipation, however, atomoxetine did not affect BOLD signal in NAc, consistent with previous reports that atomoxetine has little abuse potential. These results suggest that atomoxetine selectively modulates the activation in MPFC related to reward value encoding and, thereby, partly contributes to improvement of the reward system dysfunction in patients with ADHD.		P18-2 Effects of the adenosine A₁ receptor agonist N⁶-cyclopentyladenosine on hyper-emotionality of olfactory bulbectomized rat 嗅球摘出ラットの示す情動過多反応におけるアデノシンA₁受容体賦活薬N⁶-シクロペンチルアデノシンの作用 Gotoh Leo（後藤玲央）¹，大串祐馬²，川口貴子²，畑中聡仁²，赤崎真子³，堀之内浩介³，吉良健太郎²，川嵜弘詔² ¹Lab. of NeuroSci., Dept. of Psyc., Fac. of Med., Fukuoka Univ, Fukuoka, Japan ²Dept. of Psyc., Fac. of Med., Fukuoka Univ, Fukuoka, Japan ³Fac. of Med., Fukuoka Univ, Fukuoka, Japan In recent years, the number of patients suffering from mental illness tends to increase, and the number of patients with depression in the mood disorder area has been around 1 million. According to the estimation by the Ministry of Health, Labor and Welfare, it is reported that the social loss related to depression is 2.7 trillion yen including those related to suicide, and the clarification of the pathology of depression and development of therapeutic methods are extremely important research subjects. In the development of novel antidepressant, model animals are utilized. Olfactory bulbectomized rat (OBX) is one of model animal of depression and a widely used model for antidepressant screening and known to induce neurodegeneration including the dopamine nervous system in several brain areas. On the other hand, adenosine has been thought to function as a neuromodulator in the central nervous system. Four types of adenosine receptors (A₁, A_2a, A_2b, and A₃) have been cloned and pharmacologically characterized. Behavioral and biochemical studies have demonstrated that the adenosine A₁ and A_2a receptors (ADORA1 and ADORA2A) interact in an inhibitory manner with dopamine D₁ and D₂ receptors (DRD1 and DRD2), respectively. For example, The ADORA2A antagonist is used as a therapeutic adjunct to Parkinson's disease in which a DRD2 agonist is used as a therapeutic agent. In addition, we reported that behavioral abnormalities in rats treated with NMDA receptor inhibitor phencyclidine are improved by ADORA1 agonist N⁶-cyclopentyl adenosine (CPA) via inhibition of DRD1. However, the effect of ADORA1 stimulation on the depression like behavior of OBX has not been clarified. Therefore, we continuously administered CPA to OBX rats and confirmed the effect.

P18-3 Emotional dysregulation in mice lacking glutamate decarboxylase 67 in somatostatin neurons ソマトスタチン陽性神経特異的GAD67欠損マウスに認められる情動行動異常の解析 Kumagaya Ryota（熊谷諒太）^1,2，柿崎利和¹，藤原和之¹，若松馨²，柳川右千夫¹，宮田茂雄¹ ¹Dept. of Gen. Behav. Neurosci., Gunma Univ. ²Div. of Mol. Sci., Gunma Univ. GABA is a major inhibitory neurotransmitter in the central nervous system. GABA is synthesized from glutamate by glutamate decarboxylase (GAD), which exists in two isoforms, GAD65 and GAD67. The GABAergic neurons are classified into several subtypes using chemical markers such as parvalbumin (PV) and somatostatin (SST). In postmortem brain studies, the number of GABAergic neurons expressing SST, but not PV, were reduced in patients with major depressive disorder. Therefore, it is possible that the emotional dysregulation is associated with the functional impairment in SST-expressing GABAergic neurons. In this study, we developed the mice lacking GAD67 specifically in SST neurons (SST-GAD67 KO mice) and evaluated the emotional behaviors in those mice. In the open-field test, the time spent in the center field was significantly decreased in SST-GAD67 KO mice compared with the control mice. In the contextual conditioned fear test, the increased duration of freezing behavior was observed in SST-GAD67 KO mice in the training session, but not in the test session, compared with the control mice. These results indicate that the functional impairment in SST-expressing GABAergic neurons causes the emotional dysregulation in mice; those mice exhibited the anxiety-like and fear-like behaviors.		P18-4 Functional roles of FGF23 in the regulation of food intake during fasting 絶食時の視床下部におけるFGF23の摂食調節作用 Komori Tadasuke（小森忠祐），森川吉博 Dept. of Anat. Neurobiol., Wakayama Med. Univ. Hypothalamus is important for the regulation of energy homeostasis, including the control of food intake and energy expenditure. Previously, we reported that fasting induces the activation of ERK and CREB in the hypothalamus, suggesting that the expression of some genes is induced in the hypothalamus in response to fasting (J Neuroendocrinol, 2004). In addition, at the 59th Annual Meeting of the Japanese Society for Neurochemistry, we presented that fasting induces the expression of αKlotho in the hypothalamic arcuate nucleus, especially in NPY/AgRP neurons, and the amount of food intake after fasting is reduced in heterozygous αKlotho-deficient mice compared to wild-type mice. It is well-known that αKlotho forms the receptor complex with one of fibroblast growth factor receptors (FGFRs) and acts as the functional receptor for FGF23. However, the roles of FGF23 in the hypothalamus during fasting remain unclear. To examine the roles of FGF23 in the hypothalamus during fasting, we first measured serum concentration of FGF23 during fasting. Serum FGF23 concentration was elevated after fasting for 48 hours, suggesting that fasting may enhance the production of FGF23 in some peripheral tissues, such as bone, skeletal muscle, and spleen. Next we injected FGF23 intracerebroventricularly into fasted mice to investigate the functional roles of FGF23 in the hypothalamus. Intracerebroventricular injection of FGF23 induced the expression of Egr-1 in NPY/AgRP neurons. Amount of 2-hour food intake was increased by FGF23. In addition, FGF23 induced the mRNA expression of NPY and AgRP in the hypothalamus. These results suggest that FGF23 is a novel important regulator of food intake during fasting.

P18-5 Behavioral analysis and the validity evaluation as a mental disorder model study about Protocadherin15 deficient mice プロトカドヘリン15欠失マウスにおける行動解析とその精神病態評価 Ikeda Ryosuke（池田燎亮）¹，澤幡雅仁²，永井拓²，久島周¹，有岡祐子¹，辻村啓太¹，山田清文²，森大輔¹，尾崎紀夫¹ ¹Dept. of Psychiatry, Nagoya Univ. Grad. School of Med. ²Dept. of Neuropsychopharmacology and Hospital Pharmacy, Nagoya Univ. Grad. School of Med. Protocadherin15 (PCDH15) is a member of the cadherin superfamily that involved in generating neural diversity for neuronal differentiation and synapse formation. PCDH15 is primarily recognized as a gene that forms tip link filaments in sensory hair cells and associated with Usher syndrome type 1 (USH1), which is the most severe of the three USH subtypes due to its profound hearing loss, absent vestibular response and retinitis pigmentosa appearing at a prepubescent age. Moreover, USH has been reported to be associated with mental disorders. And, the evidences that mutations in some protocadherin are related to the onset of mental disorders have been recognized. On the other hand, the majority of phenotypic abnormalities related with PCDH15 mutations are mostly converged in the classical USH phenotypes involved in the retina and inner ear, the expression profiles and biological functions of PCDH15 in the development and adult brain are hardly elucidated. In recent years, rare copy number variations (CNVs) in PCDH15 were identified in autistic disorder (ASD) and bipolar disorder, the roles of PCDH15 in the pathogenesis of these mental disorders, however, remain elusive. In this study, in order to clarify the biological relevance between PCDH15 deletion and onset of mental disorders, we generated novel PCDH15 deficient mice in C57BL/6J strain, a standard line of behavioral analysis, performed the behavioral phenotypic analysis and evaluated the validity as a mental disorder model. In the future, clarifying the molecular pathology of abnormal behavioral phenotype in PCDH15 deficient mice and specifying the neural circuit and signaling pathway due to mutant PCDH15 would be required for establishment of drug discovery.		P18-6 L-CLEM: novel procedure for Large area Correlative Light and Electron Microscopy analysis with multi-beam scanning electron microscopy 脳の広域を光顕と電顕で比較解析するための新規L-CLEM法の開発 Iseda Taro（伊勢田太郎）^1,2，芝田晋介^1,2，三橋隆行³，大坪進矢²，信藤知子^1,2，高橋孝雄³，岡野栄之^1,2 ¹Electron microscope laboratory, Keio University School of Medicine ²慶應義塾大学医学部生理学 ³慶應義塾大学医学部小児科 Recently the Correlative light and electron microscopy (CLEM) and scanning electron microscopy (SEM) technologies were drastically improved for observing biological specimens. In order to identify the localization of the specific molecules in the tissue or cells, fluorescence labeling was usually used for the visualization with the antibody staining or with the genetic modification. Various kinds of technologies including tissue clearing enlarged the area of observation with the fluorescence labeling; however, the area of CLEM analysis was still remained restricted. To overcome this restriction, we developed a novel CLEM method using multi-beam SEM, which enabled us to carry out the large area observation at the resolution of electron microscopy level with extraordinary high speed. Here, we described the detailed procedure how to carry out this novel large-area CLEM (named as L-CLEM) with the cerebral cortex from primates and rodents. The marmoset and mouse cerebrum were labeled with several kinds of cortical layer specific markers, then whole cortex images were obtained both from fluorescence microscopy and from multi-beam SEM with the same brain. The L-CLEM approach allows us to understand the detail of neural circuitry through correlative observation of both specific molecules’ localization and synapse-level neural connection in the millimeter order large area. It is known that visualizing the detailed neural circuitry is quite important to understand the detailed brain structure. We hope this novel procedure would help to detect the abnormality of the brain suffering from the various neuropsychiatric diseases.