JaLCDOI 10.18926/AMO/32218
FullText URL fulltext.pdf
Author Matsuo, Shinji| Neya, Toshiaki| Yamasato, Teruhiro|
Abstract <p>Antroduodenal contractions were studied in rat preparations. Augmented duodenal contractions occurred spontaneously in coordination with antral contractions in normal and saline-pretreated preparations. The coordination did not occur when muscle layers and the myenteric plexus were transversely cut at the duodenum just anal to the gastroduodenal junction. In silent preparations, the coordinated contractions were produced by neostigmine or domperidone. When the antroduodenal junctional zone was pretreated with benzalkonium chloride, the augmented duodenal contractions did not occur spontaneously, and even after administration of neostigmine and domperidone although antral contractions occurred spontaneously. In these preparations, there were notably few myenteric neurons in the junctional zone, but the neurons were distributed normally in the areas where motility was recorded. The results suggest that myenteric neurons mediate antroduodenal coordinated contractions and that the coordination is modified by myenteric cholinergic excitatory and dopaminergic inhibitory pathways.</p>
Keywords gastroduodenal motility coordinated contraction myenteric plexus rat
Amo Type Article
Published Date 1991-02
Publication Title Acta Medica Okayama
Volume volume45
Issue issue1
Publisher Okayama University Medical School
Start Page 21
End Page 27
ISSN 0386-300X
NCID AA00508441
Content Type Journal Article
language 英語
File Version publisher
Refereed True
PubMed ID 2063692
Web of Sience KeyUT A1991FA75000003
JaLCDOI 10.18926/AMO/32189
FullText URL fulltext.pdf
Author Yamasato, Teruhiro| Nakayama, Sosogu|
Abstract <p>Effects of the mesenteric nerve stimulation (MNS) on the twitch contraction induced by field stimulation were investigated regarding the relationship between myenteric neurons and extrinsic cholinergic nerves in the guinea-pig mesenteric nerve-ileal preparation. The twitch contraction was inhibited after MNS. The inhibition of the twitch contraction after MNS was induced twice, just after MNS (1st inhibition) and 2-3 min later (2nd inhibition) (type I), or once, just after MNS (1st inhibition) (type II), in recovery course of twitch contraction for 6-8 min. The 1st inhibition was slightly decreased by guanethidine and hexamethonium. The inhibitory response (1st inhibition) in both types I and II was recovered to the control level by pretreatment with naloxone (recovered twitch contraction), but the late inhibitory response (2nd inhibition) was markedly observed after 2-3 min in types I and II. Either the 1st or the 2nd inhibition was not altered by capsaicin, desensitization to calcitonin gene-related polypeptide (CGRP), vasoactive intestinal polypeptide (VIP), somatostatin, or galanin. The recovered twitch contraction in types I and II was decreased by CGRP-desensitization, or capsaicin. These results suggest that the first inhibitory response was induced by enteric opioid neurons connected with extrinsic cholinergic nerves, but the 2nd inhibition was induced by unknown substances other than CGRP, VIP, somatostatin, and galanin. The twitch contraction may partly be induced by endogenous neurokinin-like substances. And, some CGRP containing neurons, which connect with extrinsic cholinergic nerves, probably activate the intrinsic excitatory neurons.</p>
Keywords mesenteric nerve myenteric neuron twitch contraction 1st inhibition 2nd inhibition
Amo Type Article
Published Date 1991-04
Publication Title Acta Medica Okayama
Volume volume45
Issue issue2
Publisher Okayama University Medical School
Start Page 67
End Page 75
ISSN 0386-300X
NCID AA00508441
Content Type Journal Article
language 英語
File Version publisher
Refereed True
PubMed ID 1678243
Web of Sience KeyUT A1991FL60800001
JaLCDOI 10.18926/AMO/31951
FullText URL fulltext.pdf
Author Miyatake, Nobuyuki| Kogashiwa, Michiko| Wang, Da-Hong| Kira, Shohei| Yamasato, Teruhiro| Fujii, Masafumi|
Abstract <p>We evaluated the visceral adipose tissue accumulation in university students in Okayama prefecture, Japan. Fifty-eight Japanese university students (10 men and 48 women, age 18.4 +/- 0.6 years)were enrolled in this study. Fat distribution was evaluated by visceral fat (V) and subcutaneous fat (S) areas measured with computed tomography (CT) scanning at umbilical levels. Anthropometric parameters,i.e., height, weight, waist circumference, hip circumference, and body fat percentage; blood examination; and blood pressure (BP) were also measured. In 58 subjects, the V area was 23.4 +/- 21.0 cm(2) and the S area was 122.5 +/- 57.9 cm(2). V areas were significantly correlated with hepatic enzymes, uric acid, triglyceride, and BP in men, while they were weakly correlated with hepatic enzymes, triglyceride, and high density lipoprotein (HDL) cholesterol in women. Correlation coefficients between V areas and clinical parameters were comparatively higher than those between other body composition parameters,i.e., S areas, weight, body mass index (BMI), body fat percentage, and clinical parameters. The present study suggests that visceral adipose tissue accumulation is important for hepatic enzymes, uric acid, triglyceride, and BP in university students.</p>
Keywords visceral adipose tissue Japanese university students lifestyle-related disease
Amo Type Article
Published Date 2005-08
Publication Title Acta Medica Okayama
Volume volume59
Issue issue4
Publisher Okayama University Medical School
Start Page 129
End Page 134
ISSN 0386-300X
NCID AA00508441
Content Type Journal Article
language 英語
File Version publisher
Refereed True
PubMed ID 16155638
Web of Sience KeyUT 000231478000003
JaLCDOI 10.18926/AMO/31771
FullText URL fulltext.pdf
Author Yamasato, Teruhiro| Takaki, Miyako| Nakayama, Sosogu|
Abstract <p>Trimebutine at low concentrations (6 X 10(-9)-1.4 X 10(-8) M) slightly enhanced the twitch response of isolated guinea pig ileum induced by transmural stimulation. At high concentrations (2 X 10(-8)-2 X 10(-7) M), however, it inhibited the twitch response in a dose dependent manner. This inhibitory effect of trimebutine was reversed by naloxone (8.1 X 10(-9) M). These results suggest that trimebutine has an opiate-like action on the myenteric plexus.</p>
Keywords naloxone trimebutine twitch respose
Amo Type Article
Published Date 1987-02
Publication Title Acta Medica Okayama
Volume volume41
Issue issue1
Publisher Okayama University Medical School
Start Page 33
End Page 35
ISSN 0386-300X
NCID AA00508441
Content Type Journal Article
language 英語
File Version publisher
Refereed True
PubMed ID 3565073
Web of Sience KeyUT A1987G146400005
JaLCDOI 10.18926/AMO/31762
FullText URL fulltext.pdf
Author Sugimoto, Masaharu| Yamasato, Teruhiro| Nakayama, Sosogu|
Abstract <p>Effects of afferent stimulation of the lingual nerve (LNAS) on gastrointestinal motility and the reflex pathways which mediate the response to LNAS were investigated in rats. LNAS induced excitatory, inhibitory or biphasic responses in the stomach, duodenum and proximal colon. These responses continued after bilateral vagotomy, but were abolished after additional bilateral splanchnicotomy or transection of the spinal cord between Th4 and Th5. The inhibitory, excitatory and biphasic responses induced by LNAS were not affected by decerebration. Both after administration of atropine (0.2 mg/kg, i.v.) and guanethidine (3-5 mg/kg, i.v.), LNAS-induced excitatory and inhibitory responses were abolished in most cases, but the slight inhibitory response in the stomach and duodenum to LNAS remained in a few cases. These results suggest that the reflex centers which cause LNAS-induced excitatory and inhibitory responses are located in the dorsal nucleus of vagus and that the reflex pathways include the vagus and splanchnic nerves.</p>
Keywords lingul nerve afferent stimulation (LNAS) vagus nerve splanchnic nerve stomach duodenum proximal colon gastrointestinal motility
Amo Type Article
Published Date 1987-06
Publication Title Acta Medica Okayama
Volume volume41
Issue issue3
Publisher Okayama University Medical School
Start Page 89
End Page 97
ISSN 0386-300X
NCID AA00508441
Content Type Journal Article
language 英語
File Version publisher
Refereed True
PubMed ID 3630763
Web of Sience KeyUT A1987H962300001
JaLCDOI 10.18926/AMO/30443
FullText URL fulltext.pdf
Author Neya, Toshiaki| Yamasato, Teruhiro| Mizutani, Masatoshi| Nakayama, Sosogu|
Abstract <p>Effects of stimulation of the vagus and sympathetic nerves on bile duct peristalses were studied in pigeons anesthetized with urethane. Vagus stimulation increased the frequency of peristalses. Atropine, hexamethonium and tetrodotoxin abolished this excitatory effect. After atropine, inhibition of peristalses sensitive to tetrodotoxin was produced. Stimulation of sympathetic area in the spinal cord inhibited peristalses. Propranolol converted this effect into an excitatory one, which was abolished by phentolamine. The results suggest that vagal and sympathetic innervations of the bile duct in pigeons are similar to those of the sphincter of Oddi in mammalian species.</p>
Keywords biliary system bile duct motility innervation pigeon
Amo Type Article
Published Date 1990-04
Publication Title Acta Medica Okayama
Volume volume44
Issue issue2
Publisher Okayama University Medical School
Start Page 113
End Page 115
ISSN 0386-300X
NCID AA00508441
Content Type Journal Article
language 英語
File Version publisher
Refereed True
PubMed ID 2363364
Web of Sience KeyUT A1990DE10000008
JaLCDOI 10.18926/AMO/30441
FullText URL fulltext.pdf
Author Yamasato, Teruhiro| Nakayama, Sosogu|
Abstract <p>The participation of the parasympathetic and sympathetic nerves in the canine gallbladder motility was examined. Efferent stimulation of the parasympathetic (vagus) and sympathetic (celiac) nerves caused contraction or inhibition of the neck, body and fundus of the gallbladder. The contractile response induced by vagus nerve stimulation was reduced by subthreshold efferent stimulation of the celiac nerve, while the inhibitory response was neither reduced nor enhanced by subthreshold efferent stimulation of the celiac nerve. The contractile and inhibitory response induced by celiac nerve stimulation was not reduced in the neck, body and fundus by subthreshold efferent stimulation of the vagus nerve. The contractile response to vagus nerve stimulation was reversed to a relaxant response by atropine administration, which was reduced or abolished by hexamethonium. It is suggested that the vagus nerve-induced contractile response in the canine gallbladder is modulated by sympathetic nerves presynaptically at the vagus nerve endings in the enteric ganglion, but the vagus nerve-induced relaxant response, which probably was induced by non-adrenergic non-cholinergic inhibitory neurons, is not modulated by the sympathetic nerves.</p>
Keywords gallbladder vagus nerve celiac nerve contractile response relaxant response
Amo Type Article
Published Date 1990-04
Publication Title Acta Medica Okayama
Volume volume44
Issue issue2
Publisher Okayama University Medical School
Start Page 79
End Page 86
ISSN 0386-300X
NCID AA00508441
Content Type Journal Article
language 英語
File Version publisher
Refereed True
PubMed ID 2363366
Web of Sience KeyUT A1990DE10000004
JaLCDOI 10.18926/AMO/30426
FullText URL fulltext.pdf
Author Wataneba, Yoshinori| Yamasato, Teruhiro| Nakayama, Sosogu|
Abstract <p>Neural regulation of the motility between the haustra and taenia coli was studied in the isolated rabbit proximal colon. Four types of haustral and taenial preparations were used: the haustral strip without the taenia coli (type 1), the haustral strip including the taenia coli (type 2), the L-shaped (taenia-haustra) preparations for recording the haustral (circular) response to taenial stimulation (type 3) and the L-shaped (haustra-taenia) preparation for recording the taenial (longitudinal) response to haustral stimulation (type 4). Field electrical stimulation induced a contractile response in the haustra and taenia coli. Hexamethonium reduced the contraction in type 2, 3 and 4 preparations. The desensitization to serotonin reduced the response in type 2 and 3 preparations. After atropinization, the response in types 1 and 4 was reversed to relaxation, and the response in types 2 and 3 was reversed to relaxation followed by contraction which was reduced or abolished by indomethacin. The responses remaining after atropinization in all types of preparations were not affected by other blocking agents tested or desensitization to neuropeptides. Tetrodotoxin abolished all relaxation and contractile responses in all types of preparations. These results suggest that the indirect contractile response to field stimulation is induced mainly via cholinergic and serotonergic neurons, and that the relaxation is mainly mediated by nonadrenergic noncholinergic neurons. The late haustral contractions after atropine may be caused by endogenous prostaglandin.</p>
Keywords proximal colon cholinergic neuron serotonergic neuron nonadrenergic noncholinergic neuron prostaglandin
Amo Type Article
Published Date 1990-08
Publication Title Acta Medica Okayama
Volume volume44
Issue issue4
Publisher Okayama University Medical School
Start Page 161
End Page 169
ISSN 0386-300X
NCID AA00508441
Content Type Journal Article
language 英語
File Version publisher
Refereed True
PubMed ID 1700874
Web of Science KeyUT A1990DX04500001