• Applied Microscopy
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• v.25 no.3
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• pp.1-19
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• 1995

The present study was performed to clarify the effect of vagus nerve stimulation on the enterochromaffin(EC) cells in the body of the stomach, the first part of the duodenum and the ceceum of rats by using routine electron microscopy and immunogold labelling. The changes in the ultrastructure and in the labelling density of the gold particles of the EC cells were investigated after vagus nerve stimulation. The vagus nerve was electrically stimulated with a square wave pulse generator for a duration of 5 minutes each, a total of 8 times at 2 minute intervals. Immunogold labelling demonstrated that the epithelial serotonin immunoreactive cells of the gastrointestinal tract are EC cells containing characteristic pleomorphic granules. Immunocytochemically labelled gold particles were largely concentrated in the dense matrix of the granules of the EC cell, and the labelling density of the gold particles considerably increased after the vagus nerve stimulation. Except for a slight activation of Golgi complexes, no remarkable changes in the ultrastructures of the EC cells were noted after the vagus nerve stimulation. The above results suggest that vagus nerve stimulation may activate serotonin biosynthesis in EC cells.

• Biomolecules & Therapeutics
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• v.1 no.1
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• pp.37-43
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• 1993

Electrical or chemical stimulation of many areas in the brainstem modulates activity of dorsal horn neurons (DHN). This is known to be mediated by a population of bulbospinal neurons. Yet, little is known about responses of DHNs to stimulation of the caudal ventrolateral medulla (CVLM). Thus, the purpose of the present study is to see if there is any change in activity of DHNs when CVLM is stimulated electrically. Thirty-one DHNs were recorded from dorsal horn of the spinal cord. Fourteen DHNs (45%) were classified as wide dynamic range neurons and 9 (19%) were high threshold cells, and 4 (13%) and 4 (13%) were deep and low threshold neurons, respectively. Among 31 neurons tested for responses to stimulation of CVLM, 21 DHNs (68%) were inhibited by the electrical stimulation of CVLM ($200{\mu}A,\;100{\mu}s$ duration, 100 Hz), and 9 cells (39%) did not show any change in neuronal activity. One neuron was excited by the stimulation. The electrical stimulation of CVLM not only inhibited spontaneous activity of DHNs but also inhibited evoked responses of DHNs to somatic stimulation in the receptive field. These data suggest that CVLM is one of the pain-modulatory areas that control transmission of ascending information of noxious input to the brain from the spinal cord.

• Physical Therapy Korea
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• v.6 no.3
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• pp.1-10
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• 1999

The purpose of this study was to determine whether high voltage pulsed current stimulation (HVPCS) would enhance wound healing in neuropathic rabbits. Ten rabbits were assigned to either an experimental or a control group. The wounded part around the peripheral neuropathy of the experimental rabbits was stimulated for two hours twice a day for six days under the following conditions: pulse frequency 80 pps, pulse duration $100{\mu}s$, and stimulation intensity 30~40 V. The results indicated that there was no difference in the wound closure between the experimental and control groups. The two groups showed similar aspects in collagen and reticulum, which were observed by colored Masson's trichome. While the rabbits in the control group had more or less thick fibers, the rabbits in the experimental group had thin and branched-shape fibers. The rabbits in the experimental group showed both strong responses in the shaping of elastic fibers and the increased aspects in fibroblast when compared with the control group.

• The Journal of the Korean dental association
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• v.16 no.7 s.110
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• pp.531-536
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• 1978

Adult cats were light anesthetized with ethyl ether and heart was removed fastly. cardiac papillary muscle was dissected from heart in organ bath con taining Tyrode solution saturated with 95% O₂+5% CO₂, and prepared papillary muscles were placed in Tyrode solution that was continuously circulated and gassed with 95% O₂+5% CO₂at 32℃. The isolated papillary muscle was stimulated continuously with platinum pin electrode at frequency of 15/min and 90/min by means of electric stimulator and transmembrane action potentials were recorded with microelectrdes on the oscilloscope. The drug used was d-propranolol and its concentration was 0.5, 1.5 and 5.0 mg/L. The results obtained were as follows: 1. D-propranolol increased the threshold voltage of papillary muscle and raised by average of 213.6% of control. 2. D-propranolol had no effect on duration of action potential. 3. Conduction time of isolated papillary muscle was increased by d-propranolol and its effect was prominent at frequency of 90/min. 4. the maximum upstroke velocity was decreased by d-propranolol and its effect was dose-depndent decrease.

• Annals of Clinical Neurophysiology
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• v.7 no.1
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• pp.13-16
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• 2005

Background: The purpose of this study is to investigate the effect of the intensive functional electrical stimulation(FES) on the improvement of the gait pattern of the chronic hemiplegic patients. Method: Six hemiplegic patients, who could walk independently but have equinovarus deformity during the gait cycle, participated in this study. The affected peroneus longus and tibialis anterior muscles of all subjects were stimulated for 2 weeks period (20 minutes duration, 6 times/day). We measured the activities (mean voltage) of those muscles during the walking, using dynamic EMG. Results: After treatment, there were significant improvements in the strength of peroneus longus and tibialis anterior muscles and the gait speed, but there was no interval change of the spasticity of plantar flexor. The mean voltages of two muscles are significantly increased in all the patients (p<0.05). Conclusion: The results showed that the intensive FES on affected peroneus longus and tibialis anterior muscles in chronic hemiplegic patients could be useful for the improvement of functional gait.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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• v.14 no.1
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• pp.31-38
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• 2008

Purpose : The purpose of this study was to compare the effectiveness of both neuromuscular electrical stimulation(NMES) and isometrical exercise(IE) to strengthen the quadriceps femoris muscle. The relationships between the strength changes and the relative force and duration of training contractions were also studied. Methods : The subjects were divided into three group. The control group(n=6) received no exercise and/or stimulation. The isometric exercise (IE) group(n=6) performed maximum isometric contractions, and the neuromuscular electrical stimulation(NMES)(n=6) engaged electrically stimulated isometric contractions, three days a week for four weeks. Results : Results showed that both IE group and NMES group were found to have an increase in strength significantly greater(p<0.05) than the control group at 4 week. But between IE group and NMES group were not found to have an difference in strength significantly. Conclusion : The relative increase in isometric strength, using IE and NMES, may be determined by the ability of the subjects to tolerate longer and more forceful contractions. Suggestions for further research and implications for the clinical of IE and NMES for strength-training are discussed.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.4
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• pp.545-552
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• 1998

This study was undertaken to clarify the effects of electrical stimulation on the biochemical properties of plaice sarcoplasmic reticulum and myofibrils at early period of death. The plaices were electrically stimulated (110V/60 Hz) In sea water bath for 15, 35, and 60 seconds, and killed instantly by spiking at the head. Killed samples were investigated for the changes in $Ca^{2+}$-ATPase activity of FSR (fragmented sarcoplasmic reticulum), LSR (light SR), HSR (heavy SR), and SDS-PAGE pattern of FSR. $Ca^{2+}$-ATPase activity of FSR increased until $45^{\circ}C$ and inactivated over $50^{\circ}C$. $Ca^{2+}$-ATPase activity of FSR remarkably decreased according to the duration of electrical stimulation. Myofibrillar $Mg^{2+}$-ATPase activity of electrically stimulated plaices in the presence of $Ca^{2+}$ was higher than that of sample instantly killed by spiking. $Mg^{2+}$-ATPase activity of myofibrils increased by electrical stimulation and the activity decreased during storage at $5^{\circ}C$. Myofibrillar $Mg^{2+}$-ATPase activity in sample killed by spiking was not affected by $Ca^{2+}$ ion. Myofibrillar $Mg^{2+}$-ATPase activity of electrically stimulated sample in the absen-re of $Ca^{2+}$ decreased during storage at $5^{\circ}C$, whit $Mg^{2+}$-ATPase activity in unstimulated sample did not show any change. $Ca^{2+}$-sensitivity of myofibrils showed no differences between electrically stimulated sample and sample killed by spiking, and the was no change during at $5^{\circ}C$.

• Biomedical Science Letters
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• v.13 no.1
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• pp.25-32
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• 2007

The purpose of this study was to investigate the effect of the high voltage pulsed Current (HVPC) stimulation on the healing rate and the proliferative activity of keratinocytes and IGF-I mRNA expression of an incisional wound in rat skin. Twenty male Sprague-Dawley rats ($265{\sim}290g$) were randomly divided into HVPC (n=10) and control group (n=10). Rats received 10 mm length of full-thickness incision wound on the back under the anesthesia. The HVPC group received electrical stimulation with a Current intensity of 50 V at 100 pps for a duration of 30 minutes, while the control group was given the same treatment without electricity for a week. Polarity was negative in first three days and positive thereafter. The wound length was measured and evaluated as percentage. The mean number of nucleolar organizer regions (NORs) per nucleus and level of IGF-I mRNA expression were calculated. The mean percent of wound closure were $51.17{\pm}17.76%$ and $80.71{\pm}11.91%$, respectively, in the sham treated control and HVPC stimulated groups (t=-4.308, P<0.001). The mean NOR number per nucleus of the keratinocytes in the control and HVPC group were $1.85{\pm}0.20$ and $2.70{\pm}0.23$, respectively (t=8.638, P<0.001). The IGF-I mRNA level were $0.76{\pm}0.44$ and $1.32{\pm}0.41$, respectively, in the control and HVPC stimulated wounds (t=2.906, P<0.01). There was a positive correlation between the mean NOR number per nucleus and IGF-l mRNA level with a Pearson product moment correlation coefficient of 0.72 (P<0.05). These findings suggest that the HVPC may activate the rRNA of the basal keratinocytes and upregulate the IGF-I mRNA levels by alteration of the electrical environment, and it may increase proliferative activity of the keratinocytes in the skin wound of the rat.

• The Korean Journal of Pharmacology
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• v.29 no.1
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• pp.121-130
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• 1993

This study was done to classify the proteins involved in the specific phosphorylation using the rat peripheral blood lymphocytes (rPBL) stimulated with mitogens, phorbol 12-myristate 13-acetate (PMA) and concanavalin A (Con A). The lymphocytes were incubated with $^{32}P-orthophosphate$ before PMA or Con A stimulation. The migration patterns of the phosphorylated proteins of mitogen-treated rPBL in two dimensional electrophoretic fields were analyzed after autoradiography. The stimulation of the lymphocytes with PMA and Con A increased the phosphorylation of thirteen protein fractions. The phosphorylation intensities of the protein spots differ to the treatments of the cells with specific kinase inhibitors, H-7 and W-7. These protein fractions were grouped into 3 classes, namely, PKC-mediated, CaM kinase-mediated, and other kinase mediated proteins. The effect of the duration of the stimulation on the phosphorylated behaviors occurred concurrently, not sequentially, although each individual protein fraction had a different time for the peak phosphorylation during the stimulation period upto 30 minutes. The phosphoproteins found in the cytosolic soluble fraction were phosphorylated prior to those in the pellet, whose phosphorylations were sustained at a high level for over 10 minutes. The above results suggest that the early events in lymphocyte activation involve 3 different sets of proteins which are phosphorylated by CaM kinase, PKC and other kinases, and those kinases do not work sequentially, but rather, independently or cooperatively.

• Journal of Periodontal and Implant Science
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• v.32 no.1
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• pp.89-112
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• 2002

The earliest reports of the use of electrical energy to directly stimulate bone healing seem to be in 1853 from England, the techniques involved the introduction of direct current into the non-united fracture site percutaneously via metallic needles, with subsequent healing of the defect. One endpoint of the periodontal therapy is to generate structure lost by periodontal diseases. Several procedural advances may support regeneration of attachment, however, regeneration of alveolar bone does not occur consistently. Therefore, factors which stimulate bone repair are areas for research in periodontal reconstructive therapy. Effects of cytokines or growth factors on bone repair are examples of such areas. Another one is electrical current which occurs in bone naturally, so that such bone may be particularly susceptible to electrical therapy. The purposes of this study were to observe the effects of electrical stimulation on the normal periodontium, to determine whether the electricity is the useful means for periodontal regeneration or not. Forty rats weighted about 100 gram were used and divided into 4 groups, the first group, there was no electrical stimulation with the connection of electrodes only. In the second group, there was stimulated by the 10 mA during 10 minutes per a day, in the third group was stimulated by the 25 mA , and the fourth by the 50 mA. At 3, 5, 10 and 15 days post-appliance , two rats in each group were serially sacrificed. and the maxillae and the mandible processed to paraffin, and the specimens were prepared with Hematoxylin-Eosin stain for the light microscopic evaluation. The results of this study were as follows : 1. There was the distinct reversal line on the lingual alveolar crest, whereas a little changes in the labial alveolarcrest to the duration and amount of currents. 2. In 50 mA group, the cells were highly concentrated at the apex of anterior teeth, and was observed the necrotic tissue. In posterior root apex, the hypercementosis was appeared, and newly formed cementum layer has been increased continuously with the time. 3. The periodontal ligament fiber and Sharpey's fiber were arranged in order, and the bone trabeculae were increased as the experiment proceeded by, relatively the bone marrows were decreased. 4. In the pulp tissue, the blood vessels were increased with blood congestion in the experimetal specimens remarkably, and the dentinal tubules were obstructed . 5. The osteoblasts in alveolar bone proper had been showed highly activity, and also observed the formation of bone trabeculea. In the conclusion, it was suggested that the electrical stimulation has influence on the periodontium and the pulp tissue. However, there might be the injurious effects.