• The Korean Journal of Pain
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• v.19 no.2
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• pp.228-232
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• 2006

Complex regional pain syndrome (CRPS) type 1 is characterized by the presence of pain, which is severe, diffuse and associated with allodynia, and is also associated with autonomic and trophic changes. The sensitization phenomena of CRPS also cause allodynia and itching, as well as pain. These symptoms are the issues associated with the treatment of CRPS. Under normal conditions, an antagonistic interaction exists between the pain and itching, but the patterns of peripheral and central sensitization phenomena for the pain and itching are very similar. The chronic pain and chronic itch have similar characteristics in their developmental and therapeutical principles. Herein, our experience of 2 cases of CRPS, which showed improvement of these facial symptoms after sphenopalatine ganglion radiofrequency thermocoagulation, but were not controlled by spinal cord stimulation or other conservative treatments, is reported.

• Science of Emotion and Sensibility
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• v.3 no.2
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• pp.17-28
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• 2000

Psychoacoustic characteristics of automobile horns play significant role in resulting subjective evaluation and psychphysiological reactions. However, comparison and differentiation of physiological responses to commercially available horns is a complicated task due to the small contrast in technical features of horns and the influence of such processes as habituation on physiological outcome with the increased number of auditory stimulation trials. In a study on 10 college students, there was performed comparative analysis of reactivity of physiological responses mediated by central and autonomic nervous systems in order to identify the role of habituation on decrement of psychophysiological responsivity and assess the ability to differentiate subjectively most and least preferred, as well as most and least appropriate horns according to physiological manifestations. The EEG and autonomic responses to 7 automobile horns were analyzed during 3 blocks of trials, with varying order of stimuli and changed acoustic parameters of horns in each block. Thus, responses were analyzed for totally 21 trials of auditory stimulation. It was shown that electrodermal and cardiovascular responses have different reactivity patterns to repeated stimulation: skin conductance measures habituated, cardiac reactivity showed no signs of habituation, and the vascular response demonstrated sensitization. The temporal EEG exhibited marked habituation of fast beta band power, while alpha-blocking effect did not habituate during the course of experiment. Differentiation of physiological responses of most and least preferred and appropriate horns was possible in our study, however, some cardiovascular reactivity measures differentiated during the entire course of the experiment, while EEG and electrodermal parameters showed significant differences only during first block of trials, and were later affected by the habituation.

• The Korean Journal of Pain
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• v.35 no.3
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• pp.240-249
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• 2022

Background: Widespread pain partially depends upon sensitization of central pain mechanisms. However, mechanisms controlling pain distribution are not completely known. The present study sought to assess skin temperature variations in the area of experimentally-induced pain and potential sex differences. Methods: Pressure-pain thresholds (PPTs) were measured on the right infraspinatus muscle. At the end of Day 0, all participants performed an eccentric exercise of the shoulder external rotators to induce muscle soreness 24 hours after. On Day 1, participants indicated on a body chart the area of pain induced by 60 seconds of suprathreshold pressure stimulation (STPS; PPT + 20%) on the right infraspinatus muscle. Skin temperature variations in the area of referred pain were recorded with an infrared thermography camera, immediately before and after the STPS. Results: Twenty healthy, pain-free individuals (10 females) participated. On Day 0, the pre-STPS temperature was higher than the post-STPS temperature on the arm (P = 0.001) and forearm (P = 0.003). On Day 1, the pre-STPS temperature was higher than the post-STPS temperature on the shoulder (P = 0.015), arm (P = 0.001), and forearm (P = 0.010). On Day 0, the temperature decrease after STPS in females was greater than in males on the forearm (P = 0.039). On Day 1, a greater temperature decrease was found amongst females compared with males at the shoulder (P = 0.018), arm (P = 0.046), and forearm (P = 0.005). Conclusions: These findings indicate that sympathetic vasomotor responses contribute to expand pressure-induced referred pain, especially among females.

• Journal of Physiology & Pathology in Korean Medicine
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• v.18 no.3
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• pp.767-773
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• 2004

Substantial evidence suggests that repeated injections of nicotine produce increase in locomotor activity and expression of the immediate-early gene, c-fos in the dopaminergic target areas. Herbal medicine as a therapeutic intervention has been widely used for the treatment of mental dysfunction. Many studies have shown that Cortex Phellodendris (CP) can affect the biochemical balance in the central nervous system. In order to investigate whether CP have an influence on their nicotine-induced behavioral sensitization, we examined the effect of CP on nicotine-induced locomotor activity and c-Fos expression in the striatum and nucleus accumbens utilizing the Fos-like immunohistochemistry (FLI). Male SD rats received CP (200㎎/㎏, i.p.) 30 min before repeated daily injections of nicotine (0.4㎎/㎏, s.c.) for 7 days. Rats were followed withdrawal for 3 days and one challenge for 1 day. System challenge with nicotine produced a much larger increase in locomotor activity and accumbal FLI. Pretreatment with CP significanly inhibited nicotine-induced locomotor activity and FLI in the striuatum and nucleus accumbens. These results demonstrated that reduction in locomotor activity by CP may be reflected by reduction of dopamine release and postsynaptic neuronal activity in the striatum and nucleus accumbens. Our results suggest that CP may have therapeutic effect on nicotine addiction. Supported by a fund (99-PJ9-PG1-002-0004).

• Biomolecules & Therapeutics
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• v.4 no.1
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• pp.1-6
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• 1996

In the present study, the antigenic potential of G009, a polysaccharide isolated from Ganoderma lucidum IY009, was determined in BALB/C mice and Hartley guinea pigs. Antigenicity tests, including passive cutaneous anaphylaxis (PCA), active systemic anaphylaxis (ASA) and indirect hemagglutination test (IHA) were performed according to the established guidelines of National Institute of Safety Research. The results were as follows: 1. Mice showed no production of antibodies against G009 sensitized with an adjuvant, aluminum hydroxide gel (alum), when judged by the heterologous PCA test in rats. Meanwhile, antibodies against ovalbumin (OVA) sensitized with alum were clearly detected. 2. In the studies with guinea pigs, both the sensitization of G009 alone and of G009 with complete Freund's adjutant (CFA) did not produce positive reactions in homologous PCA. In the case of ASA, however, G009 alone and G009 with CFA produced positive reactions. 3. No G009 specific reaction was observed in an IHA assay using sera isolated from G009 sensitized mice. These findings suggest that G009 have no antigenicity potential in mice but may have weak antigenicity in guinea pjgs.

• International Journal of Oral Biology
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• v.37 no.1
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• pp.17-23
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• 2012

Recent studies indicate that reactive oxygen species (ROS) are critically involved in persistent pain primarily through spinal mechanisms, and that mitochondria are the main source of ROS in the spinal dorsal horn. To investigate whether mitochondrial ROS can induce changes in membrane excitability on spinal substantia gelatonosa (SG) neurons, we examined the effects of mitochondrial electron transport complex (ETC) substrates and inhibitors on the membrane potential of SG neurons in spinal slices. Application of ETC inhibitors, rotenone or antimycin A, resulted in a slowly developing and slight membrane depolarization in SG neurons. Also, application of both malate, a complex I substrate, and succinate, a complex II substrate, caused reversible membrane depolarization and enhanced firing activity. Changes in membrane potential after malate exposure were more prominent than succinate exposure. When slices were pretreated with ROS scavengers such as phenyl-N-tert-buthylnitrone (PBN), catalase and 4- hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPOL), malate-induced depolarization was significantly decreased. Intracellular calcium above $100{\mu}M$ increased malateinduced depolarization, witch was suppressed by cyclosporin A, a mitochondrial permeability transition (MPT) inhibitor. These results suggest that enhanced production of spinal mitochondrial ROS can induce nociception through central sensitization.

• Biomedical Science Letters
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• v.10 no.2
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• pp.137-142
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• 2004

The peroxisome proliferator-activated receptor $\gamma$ (PPAR${\gamma}$) is the molecular target for a class of drugs, the antidiabetic thiazolidnediones (TZDs). The heterodimer of PPAR${\gamma}$ with retinoid X receptor (RXR) plays a central role in the regulation of adipogenesis and insulin sensitization. We synthesized two chemicals, DANA87 and DANA88, sharing structural characteristics with TZDs. Given this structural similarity, it was hypothesized that DANA87 and DANA88 may act as PPAR$\gamma$ ligands. In transient transfection assays, DANA87 and DANA88 caused slight increases in the endogenous expression of a luciferase reporter gene containing the PPAR responsive element in 3T3-L1 preadipocytes. However, DANA87 and DANA88 significantly inhibited troglitazone-induced reporter gene activation when cells were treated with a combination of DANA87 or DANA 88 and troglitazone, one of the TZDs that activate PPAR$\gamma$. These results suggest that DANA87 and DANA88 are not only weak agonists of PPAR${\gamma}$ transactivation, but also competitively antagonize troglitazone-induced PPAR$\gamma$ reporter activity.

• Molecules and Cells
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• v.25 no.2
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• pp.242-246
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• 2008

To assess the role of $\alpha_{1G}$ T-type $Ca^{2+}$ channels in neuropathic pain after L5 spinal nerve ligation, we examined behavioral pain susceptibility in mice lacking $Ca_{V}3.1$ (${\alpha}_{1G}{^{-/-}}$), the gene encoding the pore-forming units of these channels. Reduced spontaneous pain responses and an increased threshold for paw withdrawal in response to mechanical stimulation were observed in these mice. The ${{\alpha}_{1G}}^{-/-}$ mice also showed attenuated thermal hyperalgesia in response to both low-(IR30) and high-intensity (IR60) infrared stimulation. Our results reveal the importance of ${\alpha}_{1G}$ T-type $Ca^{2+}$ channels in the development of neuropathic pain, and suggest that selective modulation of ${\alpha}_{1G}$ subtype channels may provide a novel approach to the treatment of allodynia and hyperalgesia.

• Biomolecules & Therapeutics
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• v.26 no.5
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• pp.425-431
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• 2018

Cocaine- and amphetamine-regulated transcript (CART) peptide is a widely distributed neurotransmitter expressed in the central nervous systems. Previously, several reports demonstrated that nucleus accumbal-injected CART peptide positively modulated behavioral sensitization induced by psychostimulants and regulated the mesocorticolimbic dopaminergic pathway. It is confirmed that CART peptide exerted inhibitory effect on psychostimulant-enhanced dopamine receptors signaling, $Ca^{2+}$/calmodulin-dependent kinase signaling and crucial transcription factors expression. Besides modulation of dopamine receptors-related pathways, CART peptide also exhibited elaborated interactions with other neurotransmitter receptors, such as glutamate receptors and ${\gamma}$-aminobutyric acid receptors, which further account for attribution of CART peptide to inhibition of psychostimulant-potentiated locomotor activity. Recently, CART peptide has been shown to have anxiolytic functions on the aversive mood and uncontrolled drug-seeking behaviors following drug withdrawal. Moreover, microinjection of CART peptide has been shown to have an antidepressant effect, which suggests its potential utility in the mood regulation and avoidance of depression-like behaviors. In this review, we discuss CART pathways in neural circuits and their interactions with neurotransmitters associated with psychostimulant-induced depression.

• Nuclear Engineering and Technology
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• v.48 no.6
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• pp.1412-1422
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• 2016

Austenitic stainless steels (ASSs) are widely used for nuclear pipes as they exhibit a good combination of mechanical properties and corrosion resistance. However, high tensile residual stresses may occur in ASS welds because postweld heat treatment is not generally conducted in order to avoid sensitization, which causes a stress corrosion crack. In this study, round robin analyses on stress intensity factors (SIFs) were carried out to examine the appropriateness of structural integrity assessment methods for ASS pipe welds with two types of circumferential cracks. Typical stress profiles were generated from finite element analyses by considering residual stresses and normal operating conditions. Then, SIFs of cracked ASS pipes were determined by analytical equations represented in fitness-for-service assessment codes as well as reference finite element analyses. The discrepancies of estimated SIFs among round robin participants were confirmed due to different assessment procedures and relevant considerations, as well as the mistakes of participants. The effects of uncertainty factors on SIFs were deducted from sensitivity analyses and, based on the similarity and conservatism compared with detailed finite element analysis results, the R6 code, taking into account the applied internal pressure and combination of stress components, was recommended as the optimum procedure for SIF estimation.