本能行動 Instinctive Behavior
P1-2-152 Study the effects of endocannabinoid and endogenous cholinergic systems potentiation on the anxiety in mice ○Zoleikha Shokri1,2, Shahidi Siamak2, Dindar Asghar2, Komaki Alireza2, Sarihi Abdolrahman2, Mohammad Ahmadpanah3, Mohammad Zarei2 Clinical Psychology, Science and Research Branch, Islamic Azad University, Saveh, Tehran, Iran1, Department of Physiology & Neurophysiology Research Center, Hamadan University of Medical Sciences, Hamadan, Iran2 Introduction: Anxiety-related behavior is regulated by various neurotransmitter systems such as GABA-ergic and serotonergic systems. In the present study, we investigated the effects of augmentation of cholinergic and endocannabinoid systems and their interaction on the anxiety behavior of mice using donepezil (as an acetylcholinesterase inhibiotor) and URB-597 (as an inhibitor of endocannabinoid enzyme hydrolyse), respectively. Materials and methods: Eighty eight male mice were tested on the elevated plus maze (EPM). The elevated plus maze consisted of 2 dark closed and 2 white open arms. It was elevated 50 cm above the floor. In the EPM, the animals can actively avoid open arms. The mice were received injection of saline, diazepam (0.3 mg/kg), URB-597 (0.1, 0.3 or 1 mg/kg), donepezil (0.5, 1 or 2 mg/kg) or combined URB-597 and donepezil (low, medium or high doses of their single treatment) fifteen minutes before placing in the plus maze. The number of entries and time spent in the open and closed arms were measured. Also, total entries into the arms and percent of open to closed arm entries and time spent ratio were measured. Results: The results showed that administration the used doses of URB-597, donepezil and diazepam increased the number of open arms exploration and decreased the number of closed arms exploration in compare with saline treated group. Combined treatment with URB-597 and donepezil did not affect open arm exploration and it decreased closed arms exploration. Conclusion: It can be concluded that augmentation of each cholinergic or endocannabinoid system exerts anxiolytic effect, as well as diazepam. Although, their combined potentiation decreased locomotor activity it exerts anxiolytic with lower degree their single treatment. It seems that there is interaction between cholinergic and endocannabinoid which inactive their anxiolytic effects.	P1-2-153 新規な初期応答遺伝子Hr38を用いたショウジョウバエ脳においてメスに反応する神経細胞の検出 Detection of neurons which respond to female in the brain of male Drosophila by a novel immediate early gene, Hr38 ○木矢剛智1, 佐藤優希1, 岩見雅史1 ○Taketoshi Kiya1, Yuuki Sato1, Masafumi Iwami1 金沢大・院自然・生物科学1 Div. of Life Sci., Grad. Sch. of Nat. Sci. & Tec., Kanazawa Univ., Kanazawa, JAPAN1 Insects exhibit a variety of interesting instinct behaviors. Because insects have relatively simple brains and their instinct behaviors are stereotypic, it is advantageous to analyze the relationships between neural circuits and behavior. Immediate early genes (IEGs), whose expression is rapidly upregulated by neural activity, are often used as a powerful approach to map the neural activity of free-moving animals in vertebrates. In insects, however, no IEG has been identified so far. Recently, we identified a novel IEG, Hr38, which can be used as a neural activity marker in silkworms, fruit flies, and honeybees. To elucidate neural circuits which underlie the sex pheromone detection system, we investigated Hr38 expression in the brain of male Drosophila, which is stimulated with a decapitated virgin female. By in situ hybridization, we found that a small number of antennal lobe neurons (5~10) and a large number of mushroom body neurons (40~50) are active in response to the female stimulation. The number of Hr38-positive neurons in response to the female stimulation was not affected by the genetic removal of sex pheromone receptor (Or47b) neurons nor surgical removal of the forelegs, but significantly reduced when both Or47b neurons and forelegs are removed. Furthermore, most of the Hr38-positive neurons were negative to fru, which is an essential sex determination gene. These results suggest that a neural circuit independent from fru is strongly activated by the female stimulation. To further investigate this neural circuit, we developed a novel activity-dependent neural tracing method. Hr38 is a transcription factor and binds to a conserved 9 nucleotides called NBRE. By utilizing NBRE, we successfully detected the activity-dependent gene expression. Our approach is expected to reveal the neural circuit of instinct behavior.
P1-2-154 レチノイン酸情報伝達系機能阻害による情動行動異常 Dysfunction of RARs-signaling pathway impairs emotional behaviors in mice ○篠澤貴寛1, 齋藤香織1, 野本真順1,2, 内田周作1, 喜田聡1,2 ○Takahiro Shinozawa1, Kaori Saito1, Masanori Nomoto1,2, Syusaku Uchida1, Satoshi Kida1,2 東京農大院・農・バイオ1, 科学技術振興機構2 Dept.of Bioscience, Tokyo Univ.of Agriculture1, CREST,JST2 Retinoic acid (RA), a metabolite of Vitamin A, acts as a specific ligand for retinoic acid receptors (RARs). RARs function by forming a heterodimer with retinoid X receptors (RXRs) and regulate various biological phenomena through transcriptional regulation. Importantly, RARs highly and ubiquitously express in the brain. Previous studies reported that RARβ/RXRγ double-knockout mice displayed a decrease in expression of dopamine D2 receptor in the striatum and a deficit in locomotor activity (Krezel et al., 1998), suggesting that RARs may play important roles in emotional behavior. In this study, to understand roles of RARs in emotional behaviors, we examined effects of loss- or gain- of-RARs function on emotional behaviors by analyzing mutant mice that show forebrain-specific expression of dominant negative mutant of RARα (dnRAR) or wild type RARα (wtRAR) using a tetracycline-dependent transgene expression system. In light/dark transition test, dnRAR-expressing mice displayed a significant increase in latency to light box. Similarly, in the open field test, dnRAR mice displayed significant decreases in locomotor activity and time spent in the center of the field for first 5 min. These results suggest that dnRAR mice exhibit anxiety-like behaviors. However, locomotor activities of dnRAR mice in the open field had maintained for 120 min since these mice were placed in the field although WT mice displayed gradual decreases in locomotor activity. Consistently, dnRAR mice displayed significant increases in home cage activity. Finally, dnRAR mice displayed significant decreases in immobility time in forced swim and tail suspension tests, indicating that dnRAR mice exhibit mania-like behaviors. Taken together, our results suggest that dnRAR mice display anxiety-like behaviors in response to novel environment although they usually display mania-like behaviors. Thus RAR-signaling pathway in the forebrain plays regulatory roles in emotional behaviors.	P1-2-155 キイロショウジョウバエにおける匂いに対する嗜好性を制御する神経メカニズムの解明 Neural mechanisms underlying odor preference choice in Drosophila ○大領悠介1,2, 金井誠2, 榎本和生2 ○Yusuke Dairyo1,2, Makoto Kanai2, Kazuo Emoto2 奈良先端科学技術大学院大学・バイオ1, 大阪バイオサイエンス研究所・神経細胞生物2 Biosci., NAIST, Nara1, Dept. of Cell Biol., OBI2 The behavior of animals is flexible and can be changed dramatically in response to the environment, nutritional state, or even age. However, the neural basis of how external and internal cues modify the innate behaviors is not clearly understood. We focused on the odor preference behaviors in Drosophila larvae as a model system and found that the third instar larvae dramatically change their odor preference during the late larval stages. For example, early third instar larvae (96 hours after egg laying) are strongly attracted by 1-hexanol, whereas wandering larvae (120 hours after egg laying) show less interest to the same odor. This suggests that neural circuits that determine the odor preference might be modified during 24 hours prior to metamorphosis. To elucidate the neural mechanisms underlying the preference change, we attempted to identify neurons involved in the odor preference choice by genetically manipulating neuronal functions. To do that, we have first established a quantitative assay system for the larval odor preference behaviors and then conducted a couple of genetic screens. So far, we have identified candidate neurons involved in the preference choice, which including the D1 dopamine receptor DopR expressing neurons. Based on these findings, we would like to discuss how the brain makes decision and also change the decision against the same sensory information.
P1-2-156 インスリン分泌細胞におけるPain TRPチャネルおよびインスリン様ペプチドの発現はショウジョウバエメスの性的受容性の制御に関与する Expression of Pain TRP channels and Insulin-like peptides in the insulin producing neurons is involved in the regulation of sexual receptivity in Drosophila virgin females ○渡辺一輝1, 坂井貴臣1 ○Kazuki Watanabe1, Takaomi Sakai1 首都大院・理工学・生命科学1 Dept Biol, Tokyo Metropolitan Univ., Tokyo1 In the fruit fly, Drosophila melanogaster, females evaluate potential mating partners and decide whether to mate or not. However, little is known about the molecular and neuronal mechanisms regulating the sexual receptivity in virgin females. Previously, we found that the Drosophila painless gene (pain), which encodes transient receptor potential (TRP) ion channel, is required for regulation of sexual receptivity in virgin females and mutations in pain enhance female sexual receptivity. Knocking down of pain expression in the insulin-producing cells (IPCs) in the adult brain enhances female sexual receptivity. In addition, genetic ablation of the IPCs and conditional suppression of neurosecretion in the IPCs also enhance female sexual receptivity. These results suggested to us that a decrease in pain in the IPCs leads to decrease synaptic transmission or hormone secretion. In this current study, we examined whether a decrease in Drosophila Insulin-like peptides in the IPCs affect female sexual receptivity. In Drosophila, Insulin-like peptide 2, 3, and 5 (Ilp2, Ilp3, and Ilp5) are co-expressed in the IPCs and these three genes are under individual transcriptional control. In virgin females, targeted expression of Ilp5 RNAi in the IPCs evaluated the mating success rate and shortened the time to copulate after males initiate courtship behavior, indicating that Ilp5 plays a role in the regulation of sexual receptivity in Drosophila virgin females. Since Pain TRP is a cation channel with extremely high Ca2+ permeability, it is possible that pain mutations cause a decrease in the level of intracellular Ca2+, which consequently reduces secretion of Insulin-like peptides in the IPCs.

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