Effects of electroacupuncture on stress and anxiety-related responses in rats

ABSTRACT The aim of this work was to investigate if eletroacupuncture at PC6 would modulate the stress-induced anxiety-like behavior and the level of activation of several brain areas. Rats were distributed in groups: control; submitted to immobilization; submitted to immobilization and eletroacupuncture at PC6 or at the tail. Immobilization increased grooming and decreased stretched attend postures and the time spent in the open arms of the ele-vated plus-maze. Eletroacupuncture at PC6 or tail canceled the effect of immobilization on grooming and attenuated the stretched attend posture. Immobilization increased Fos-immunoreactivity in the prefrontal cortex, medial and central amygdala, paraventricular and dorsomedial nuclei of the hypothalamus, lateral hypothalamus, dentate gyrus, CA1, CA2 and CA3 hippocampal areas. The activation of paraventricular, dorsomedial nuclei and prefrontal cortex by immobilization was canceled by electroacupuncture at PC6 and attenuated by electroacupuncture in the tail. The activation of the other areas was canceled by electroacupuncture in PC6 or the tail. It is concluded that immobilization induced anxiety-like behavior that was moderately attenuated by eletroacupuncture with difference between the stimulation in PC6 or the rat tail. Eletroacupuncture showed specificity concerning to the attenuation of the effects of immobilization in the CNS areas related to the stress response, anxiety and cardiovascular system.

The Effect and the Mechanism of Action of High Frequency Electrical Stimulation of Subthalamic Nucleus on Status Epilepticus Induced by Lithium-Pilocarpine of Rat / 대한간질학회지

OBJECTIVES: Deep brain stimulation (DBS) of subthalamic nuclei (STN) is one of the current modalities of refractory epilepsy, but its exact mechanism and route of action have not been elucidated yet. We investigated the effect of STN stimulation on the development and propagation of seizures in the rats with lithium-pilocarpine induced status epilepticus in its functional anatomy. METHODS: Both pilocarpine injection and high frequency stimulation on STN (HFSSTN) were provided to rats (STN group, n=12), but pilocarpine injection with no stimulation was done on the sham group (n=8). The latency to first discrete ictal discharges and the latency to status epilepticus (SE) were analyzed and the electrical stimulation lasted for 30, 60, 90, 120 minutes after its first discrete spikes. After stimulation, the rats were immediately decapitated for immunohistochemistry and histologic examination. RESULTS: Both the latency to first discrete ictal discharges and the latency to the onset of SE were delayed in the STN group than in the sham group. The latency to the first SE was also more delayed in the STN group (42.7+/-7.9 min) than in the sham group (p<0.05). Remarkably, there was marked Fos immunoreactivity (FIR) on the reticular thalamic nuclei in the STN group, but not in the sham group. CONCLUSIONS: Increased FIR in the reticular thalamic nuclei during HFSSTN suggested that the facilitation of the inhibitory thalamic output prevented generalized motor seizure behavior. We assume that HFSSTN has a pivotal role in the suppression or progression to SE, but cannot prevent seizure onset.

Pre-Clinical Study of Risperidone / 대한정신약물학회지

Pre-clinical study has been carried out to explore the pharmacology, mechanism of actions, and toxicology of candidate materials for the new therapeutic drugs, and the additional biological mechanisms of drugs prescribed presently in clinical practice. The in vitro study has been applied for the mechanism of actions at the molecular level, drug resistance, determining factors on drug responses, intracellular pharmacodynamics, and molecular pharmacology, and the in vivo study for the therapeutic effects in living animals, toxicology, and determination of initial clinical doses. The pre-clinical studies of risperidone have been reported in Korea only a few papers of biochemical studies related with dopamine neurotransmission, Fos-immunoreactivity, animal models of obsessivecompulsive disorder, and neuroprotection in dementia. In this manuscript, some issues focused on the pre-clinical studies of risperidone in Korea were summarized with the journal reviews through the PubMed.