Sensations from viscera, like fullness, easily become painful if the stimulus persists. Mice lacking alpha1G T-type Ca2+ channels show hyperalgesia to visceral pain. Thalamic infusion of a T-type blocker induced similar hyperalgesia in wild-type mice. In response to visceral pain, the ventroposterolateral thalamic neurons evokeda surge of single spikes, which then slowly decayed as T type-dependent burst spikes gradually increased. In alpha1G-deficient neurons, the single-spike response persisted without burst spikes. These results indicate that T-type Ca2+ channels underlie an antinociceptive mechanism operating in the thalamus andsupport the idea that burst firing plays a critical role in sensory gating in the thalamus.

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N-type calcium channels are modulated by acute and chronic ethanol exposure in vitro at concentrations known to affect humans, but it is not known whether N-type channels are important for behavioral responses to ethanol in vivo. Here, we show that in mice lacking functional N-type calcium channels, voluntary ethanol consumption is reduced and place preference is developed only at a low dose of ethanol. The hypnotic effects of ethanol are also substantially diminished, whereas ethanol-induced ataxia is mildly increased. These results demonstrate that N-type calcium channels modulate acute responses to ethanol and are important mediators of ethanol reward and preference.

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Voltage-dependent N-type Ca2؉ channels play important roles in the regulation of diverse neuronal functions in the brain, but little is known about its role in social aggressive behaviors. Mice lacking the ␣1B subunit (Ca v 2.2) of N-type Ca 2؉ channels showed markedly enhanced aggressive behaviors to an intruder mouse in the resident-intruder test. The dorsal raphe nucleus (DRN), which contains serotonin neurons, is known to be involved in aggression in animals. We thus examined the DRN neurons in the Ca v 2. (2-6), there was no study of the role of N-type Ca 2ϩ channels in aggression. It is believed that most social animals possess neural mechanisms for the control of aggression, which is essential for maintenance of beneficial relationships among members in a community. Aggression is considered a complex social behavior influenced by both internal (e.g. hormones or genes) and external stimuli (e.g. drive, TV, and frustration etc.) (7). Deficit of the control mechanisms for suppression of aggression might be implicated in the development of violence in various psychiatric disorders, such as attention deficit/hyperactivity disorder (ADHD) and personality disorders (8, 9).The modulation of aggression has been associated with a change in the central serotonin (5-HT) system at the dorsal raphe nucleus (DRN) (10 -14). In the DRN, the 5-HT neuronal activity showing a slow and regular firing pattern (15-17) is known to be influenced by ␥-aminobutyric acid (GABA), 5-HT 1A autoreceptor, and noradrenergic input (17). Furthermore, the modulation of these signals in the DRN affected aggression behaviors in animals (10 -13, 18, 19).It has been shown that the Ca v 2.2 is highly expressed in the DRN of adult rats (20). However, the role of Ca v 2.2 in the DRN has not been examined, nor has the involvement of Ca v 2.2 in the regulation of aggression. Therefore, we have characterized aggression behaviors of Ca v 2.2 Ϫ/Ϫ mice and investigated the properties of the Ca v 2.2 Ϫ/Ϫ DRN neurons. Interestingly, the Ca v 2.2 Ϫ/Ϫ mice exhibited an enhanced aggressive behavior and a reduced inhibitory transmission in the DRN. In addition, Ca v 2.2 Ϫ/Ϫ mice showed an increased level of arginine vasopressin (AVP) in the cerebrospinal fluid (CSF), together with an increase of 5-HT in the hypothalamus. Our results suggest a possibility that the N-type Ca 2ϩ channel plays a critical role in the suppression of aggressive behaviors. EXPERIMENTAL PROCEDURESAnimals-All of the animals were handled in accordance with the animal care and use guidelines of the Korea Institute of * This work was supported by a National Honor Scientist grant from the Ministry of Science and Technology, Korea, and the Chemoinformatics program, the Center-of-Excellence program, and the Top-Brand program in Korea Institute of Science and Technology, Korea. The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore be hereby marked "advertisement" in accordance with 18 U.S.C. Section 1734 solely to indicate t...

Rao-Blackwellized Particle Filter and FastSLAM have become popular tools to solve the Simultaneous Localization and Mapping (SLAM) problem. However, the above techniques have two important potential limitations, which are the derivation of the Jacobian matrices and the linear approximations to the nonlinear functions. Also, one of the major challenges of both Rao-Blackwellized particle filter and FastSLAM is to reduce the number of particles while maintaining the estimation accuracy. This paper proposes a new algorithm based on unscented transformation called Unscented FastSLAM (UFastSLAM) that overcomes important drawbacks of the Rao-Blackwellized particle filter frameworks by directly using nonlinear relations. Experimental results in large scale environments are presented that demonstrate the effectiveness of the UFastSLAM algorithm over the previous approaches.

There is a clear need for new therapeutics to treat alcoholism. Here, we test our hypothesis that selective inhibitors of neuronal calcium channels will reduce ethanol consumption and intoxication, based on our previous studies using knock-out mice and cell culture systems. We demonstrate that pretreatment with the novel mixed N-type and T-type calcium channel antagonist 1-(6,6-bis(4-fluorophenyl)hexyl)-4-(3,4,5-trimethoxybenzyl)piperazine (NP078585) reduced ethanol intoxication. NP078585 also attenuated the reinforcing and rewarding properties of ethanol, measured by operant self-administration and the expression of an ethanol conditioned place preference, and abolished stress-induced reinstatement of ethanol seeking. NP078585 did not affect alcohol responses in mice lacking N-type calcium channels. These results suggest that selective calcium channel inhibitors may be useful in reducing acute ethanol intoxication and alcohol consumption by human alcoholics.