• Journal of Yeungnam Medical Science
• /
• v.8 no.2
• /
• pp.95-105
• /
• 1991

This study was designed to investigate the effect of GABA and related substances on the spontaneous contraction of rat small intestine. The rats(Sprague-Dawley), weighing 200-250g, were sacrificed by cervical dislocation, and the small intestine was isolated. Longitudinal muscle strips from duodenum, jejunum and ileum were suspended in Biancani's isolated muscle chambers and myographied isometrically. GABA and muscimol, a GABA A receptor agonist relaxed the duodenum and jejunum significantly, but baclofen-induced relaxation in those muscle strips was negligible. The effectiveness of GABA and muscimol in various regions were the greatest on duodenum, and greater on jejunum than on ileum The effect of GABA and muscimol was antagonized by bicuculline, a compeptitive GABA A receptor antagonist and picrotoxin, a noncomptitive GABA A receptor antagonist. Duodenal relaxation induced by GABA and muscimol was unaffected by hexamethonium, but was prevented by tetrodotoxin. These results suggest that GABA inhibit the contractility of smooth muscle with distinct regional difference of efficacy, and the site of inhibitory action is the GABA A receptor existing at the presynaptic membrane of postganglionic excitatory nerves.

• The Korean Journal of Physiology and Pharmacology
• /
• v.20 no.5
• /
• pp.499-505
• /
• 2016

The quantitative sudomotor axon reflex testing (QSART) is a classic test of routine postganglionic sudomotor function. We investigated sudomotor function by QSART after summer (July 2012) and winter (January 2013) seasonal acclimation (SA) in the Republic of Korea. QSART with acetylcholine (ACh) iontophoresis were performed to determine directly activated (DIR) and axon reflex-mediated (AXR1, 2) sweating rate. Onset time of axon reflex, activated sweat gland density (ASGD), activated sweat gland output (ASGO), tympanic and skin temperatures ($T_{ty}$, $T_{sk}$), basal metabolic rate (BMR), and evaporative loss volume changes were measured. Tympanic and mean body temperature (${\bar{T}}_b$; calculated from $T_{ty}$, $T_{sk}$) were significantly lower after summer-SA than that of winter-SA. Sweat onset time was delayed during winter-SA compared to that after summer-SA. BMR, AXR(1), AXR(2), and DIR sweat rates, ASGD and ASGO, and evaporative loss volume were significantly diminished after winter-SA relative to after summer-SA. In conclusion, changes in sweating activity measured by QSART confirmed the involvement of the peripheral nervous system in variation of sudomotor activity in seasonal acclimation.

• The Korean Journal of Physiology
• /
• v.29 no.2
• /
• pp.309-321
• /
• 1995

In the present study, the relationship between the somatosympathetic reflexes and arterial blood pressure responses to electrical stimulation of the peripheral nerve was investigated in cats anesthetized with ${\alpha}-chloralose$. Single sympathetic postganglionic fiber activities were recorded from the hindlimb muscle and skin nerves and also from the cervical and abdominal sympathetic chains. Effects of the morphine on responses of the sympathetic nerve and arterial blood pressure to activation of the peripheral $A{\delta}-$ and C-afferent nerves were analyzed. The following results were obtained. 1) Arterial blood pressure was depressed by peripheral AS-afferent stimulation (A-response) and was elevated during C-afferent activation (C-response). 2) Intravenously administered morphine enhanced the C-response while the A-response decreased insignificantly, Only the C-response was decreased by intrathecal morphine. 3) All the ten recorded cutaneous sympathetic fibers showed periodic discharge pattern similar to respiratory rhythm and five of them also showed cardiac-related rhythm. However, most of the muscular sympathetic fibers had cardiac-related rhythm and only four fibers showed respiratory rhythm. 4) Morphine decreased the sympathetic C-reflex elicited by the peripheral C-afferent activation and the abdominal sympathetic A-reflex was also decreased by morphine. From the above results, it was concluded that supraspinal mechanisms were involved in the enhanced arterial pressor response to peripheral C-afferent activation by intravenous morphine.

• Applied Microscopy
• /
• v.26 no.3
• /
• pp.349-367
• /
• 1996

The development of small granule-containing cell in the superior cervical ganglion was studied by electron microscopic method in human fetuses ranging from 40 mm to 260 mm crown rump length (10 to 30 weeks of gestational age). At 40 mm fetus, the superior cervical ganglion was composed of clusters of undifferentiated cells, primitive neuroblasts, and unmyelinated nerve fibers together with blood vessels. At 90 mm fetus, the superior cervical ganglion consisted of neuroblasts, satellite cell, small granule-containing cells, and unmyelinated nerve fibers. Two morphological types of the small granule-containing cells in the superior cervical ganglion were first indentified at 90 mm fetus, but were rare. Type I granule-containing cell occurred in solitary and had long processes, whereas type II cells tend to appeared in clusters near the blood capillaries. The granule-containing cells were characterized by the presence of dense-cored vesicles ranging from $150{\sim}300nm$ in diameter in both the cell bodies and processes. Other organelles included abundant mitochondria, rough endoplasmic reticulum, neurotubules, and widely distributed ribosomes. The granule-containing cells had long processes similar to those found in principal ganglionic cells. They could be identified by their content in dense-cored vesicles. The small granule-containing cells increased somewhat in size and number with increase of fetal age. Synaptic contacts were first found on the solitary granule-containing cell at 150 mm fetus. Synaptic contacts between the soma and processes of type I granule-containing cells and preganglionic axon terminals were observed. In addition, synaptic junctions between the processes of granule-containing cells and presumed dendrite of postganglionic neuron were also observed from 150 mm onward. On the basis of these features type I granule-containing cells could be considered as interneurons. The clusters of type II granule-containing cells were located in the interstitial or subcapsular portions of the ganglion, and had short processes which ended in close relation to fenestrated capillaries. Therefore it may be infer that clusters of type II granule-containing cells have an endocrine function.

• The Korean Journal of Pharmacology
• /
• v.19 no.1
• /
• pp.85-92
• /
• 1983

Intestine is innervated by an interconnected plexus of both sympathetic and parasympathetic nerve fibers. Sympathetic influence causes inhibition of intestinal motility mediated by both ${\alpha}-\;and\;{\beta}-adrenergic$ receptors. The mechanism of intestinal relaxation by ${\beta}-receptors$ has been extensively studied, but the function of ${\alpha}-receptors$ in intestinal motility is still unclear. Although it is suggested that catecholamine reduces acetylcholine release and this may play an important role in ${\alpha}-receptor$ mediated intestinal relaxation, there is no definite evidences about the mechanism and site of action of ${\alpha}-receptor$ mediated relaxation. In this experiment, therefore, the effect and site of action of ${\alpha}-receptor$ agonists were investigated in the guinea pig ileum using electrical field stimulation. The results are summarized as follows : 1) Electrical field stimulation elicited tonic contraction in isolated guinea pig ileum ana this contraction was completely inhibited by the pretreatment of tetrodotoxin or atropine. 2) Norepinephrine, epinephrine and dopamine inhibited the contraction induced by electrical field stimulation but methoxamine and phenylephrine had little effects. 3) Inhibitory effects of norepinephrine and dopamine was partially blocked by yohimbine and phentolamine pretreatment. But haloperidol and propranolol pretreatment cause no effects on the electrical field stimulation induced contraction. Inhibitory effect of dopamine was completely blocked by both haloperidol and yohimbine pretreatment. 4) Inhibitory effects of norepinephrine and dopamine were little affected by the pretreatment with hexamethonium. It is suggested that electrical field stimulation causes tonic contraction of guinea pig ileum by releasing acetylcholine from postganglionic fiber, and this release is blocked by presynaptic ${\alpha}-receptor$ activation.

• Journal of Korean Orthopaedic Sports Medicine
• /
• v.5 no.2
• /
• pp.117-122
• /
• 2006

Purpose: The purpose of this study is to investigate the relationship between rotator cuff tear and nerve injury, and prevalence of nerve injury using electromyographic study. Materials and Methods: From May 2004 to Feb. 2005, 19 cases, who underwent surgery for full-thickness rotator cuff tear, were evaluated for nerve injury using electomyogram instruments preoperatively. Rotator cuff tears caused by acute high energy trauma were excluded in this study. Mean age was 59 (range, 45-87) years and mean duration of symptoms was 45 (range, 1-360) month. Results: There were six nerve injuries (31.6%). All of them were incomplete brachial plexus injuries, and mainly postganglionic lesions. Four cases among them had minor trauma history. There were no significant differences in terms of cuff tear size, range of motion, pain score and functional score between groups with and without nerve injury. Conclusion: This study showed high prevalence (31.6%) of nerve injury in full-thickness rotator cuff tear. So careful physical examination and evaluation for nerve injury are needed in rotator cuff tear.

• Journal of the Korean Orthopaedic Association
• /
• v.54 no.5
• /
• pp.463-468
• /
• 2019

Congenital insensitivity to pain with anhidrosis (CIPA) is a rare disease that affects the sensory and autonomic nervous system. The patients do not have the ability to sense different sensations, such as pain, which tends to lead to different injuries. In addition, the patients suffer from fluctuations in body temperature due to autonomic involvement. The present case was a five-year-old girl with a neglected distal femur fracture. X-rays taken during the follow-up showed marked callus formation and pseudarthrosis of the distal femur. She had biting injuries of the tongue, auto-amputation of the fingers, some developmental delay and a history of recurrent fever with an unknown origin. The electrodiagnostic study was normal. The quantitative sudomotor axon reflex test revealed markedly reduced postganglionic sudomotor axonal responses at all sites recorded on the left. She was diagnosed with CIPA. As the initial presentation of CIPA involves the musculoskeletal system, orthopedic surgeons should have a high index of suspicion.

• Korean Journal of Veterinary Research
• /
• v.43 no.1
• /
• pp.11-24
• /
• 2003

This experimental studies was to investigate the location of PNS and CNS labeled neurons following injection of 2% WGA-HRP and pseudorabies virus (PRY), Bartha strain, into the ductus deferens of rats. After survival times 4-5 days following injection of 2% WGA-HRP and PRV, the rats were perfused, and their brain, spinal cord, sympathetic ganglia and spinal ganglia were frozen sectioned ($30{\mu}m$). These sections were stained by HRP histochemical and PRY inummohistochemical staining methods, and observed with light microscope. The results were as follows ; 1. The location of sympathetic ganglia projecting to the ductus deferens were observed in pelvic ganglion, inferior mesenteric ganglion and L1-6 lwnbar sympathetic ganglia. 2. The location of spinal ganglia projecting to the ductus deferens were observed in T13-L6 spinal ganglia. 3. The PRY labeled neurons projecting to the ductus deferens were observed in lateral spinal nucleus, lamina I, II and X of cervical segments. In thoracic segments, PRY labeled neurons were observed in dorsomedial part of lamina I, II and III, and dorsolateral part of lamina IV and V. Densely labeled neurons were observed in intermediolateral nucleus. In first lumbar segment, labeled neurons were observed in intermediolateral nucleus and dorsal commisural nucleus. In sixth lumbar segment and sacral segments, dense labeled neurons were observed in sacral parasympathetic nuc., lamina IX and X. 4. In the medulla oblongata, PRV labeled neurons projecting to the ductus deferens were observed in the trigeminal spinal nuc., A1 noradrenalin cells/C1 adrenalin cells/caudoventrolateral reticular nuc., rostroventrolateral reticular nuc., area postrema, nuc. tractus solitarius, raphe obscurus nuc., raphe pallidus nuc., raphe magnus nuc., parapyramidal nuc., lateral reticular nuc., gigantocellular reticular nuc.. 5. In the pons, PRV labeled neurons projecting to the ductus deferens were ohserved in parabrachial nuc., Kolliker-Fuse nuc., locus cooruleus, subcooruleus nuc. and AS noradrenalin cells. 6. In midbrain, PRV labeled neurons projecting to the ductus deferens were observed in periaqueductal gray substance, substantia nigra and dorsal raphe nuc.. 7. In the diencephalon, PRV labeled neurons projecting to the ductus deferens were observed in paraventricular hypahalamic nuc., lateral hypothalamic nuc., retrochiasmatic nuc. and ventromedial hypothalamic nuc.. 8. In cerebrum, PRV labeled neurons projecting to the ductus deferens were observed in area 1 of parietal cortex. These results suggest that WGA-HRP labeled neurons of the spinal cord projecting to the rat ductus deferens might be the first-order neurons related to the viscero-somatic sensory and sympathetic postganglionic neurons, and PRV labeled neurons of the brain and spinal cord may be the second and third-order neurons response to the movement of smooth muscles in ductus deferens. These PRV labeled neurons may be central autonomic center related to the integration and modulation of reflex control linked to the sensory and motor system monitaing the internal environment. These observations provide evidence for previously unknown projections from ductus deferens to spinal cord and brain which may be play an important neuroanatornical basic evidence in the regulation of ductus deferens function.

• Tuberculosis and Respiratory Diseases
• /
• v.49 no.4
• /
• pp.486-494
• /
• 2000

Background : The dominant innervation of airway smooth muscle is parasympathetic fibers which are carried in the vagus nerve. Activation of these cholinergic nerves releases acetylcholine which binds to $M_3$ muscarinic receptors on the smooth muscle causing bronchocontraction. Acetylcholine also feeds back onto neuronal $M_2$ muscarinic receptors located on the postganglionic cholinergic nerves. Stimulation of these receptors further inhibits acetylcholine release, so these $M_2$, muscarinic receptors act as autoreceptors. Loss of function of these $M_2$ receptors, as it occurs in animal models of hyperresponsiveness, leads to an increase in vagally mediated hyperresponsiveness. However, there are limited data pertaining to whether there are dysfunctions of these receptors in patients with asthma. The aim of this study is to determine whether there are dysfunction of $M_2$ muscarinic receptors in asthmatic patients and difference of function of these receptors according to severity of asthma. Method : We studied twenty-seven patients with asthma who were registered at Pulmonology Division of Korea University Hospital. They all met asthma criteria of ATS. Of these patients, eleven patients were categorized as having mild asthma, eight patients moderate asthma and eight patients severe asthma according to severity by NAEPP Expert Panel Report 2(1997). All subjects were free of recent upper respiratory tract infection within 2 weeks and showed positive methacholine challenge test ($PC_{20}$<16mg/ml). Methacholine provocation tests were performed twice on separate days allowing for an interval of one week. In the second test, pretreatment with the $M_2$ muscarinic receptor agonist pilocarpine($180{\mu}g$) through inhalation was performed be fore the routine procedures. Results : Eleven subjects with mild asthma and eight subjects with moderate asthma showed significant increase of $PC_{20}$ from 5.30$\pm$5.23mg/ml(mean$\pm$SD) to 20.82$\pm$22.56mg/ml(p=0.004) and from 2.79$\pm$1.51mg/ml to 4.67$\pm$3.53mg/ml(p=0.012) after pilocarpine inhalation, respectively. However, in the eight subjects with severe asthma significant increase of $PC_{20}$ from l.76$\pm$1.50mg/ml to 3.18$\pm$4.03mg/ml(p=0.161) after pilocarpine inhalation was not found. Conclusion : In subjects with mild and moderate asthma, function of $M_2$ muscarinic receptors was normal, but there was a dysfunction of these receptors in subjects with severe asthma. ηlese results suggest that function of $M_2$ muscarinic receptors is different according to severity of asthma.