JaLCDOI 10.18926/AMO/31771
フルテキストURL fulltext.pdf
著者 Yamasato, Teruhiro| Takaki, Miyako| Nakayama, Sosogu|
抄録 <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>
キーワード naloxone trimebutine twitch respose
Amo Type Article
発行日 1987-02
出版物タイトル Acta Medica Okayama
41巻
1号
出版者 Okayama University Medical School
開始ページ 33
終了ページ 35
ISSN 0386-300X
NCID AA00508441
資料タイプ 学術雑誌論文
言語 English
論文のバージョン publisher
査読 有り
PubMed ID 3565073
Web of Sience KeyUT A1987G146400005
JaLCDOI 10.18926/AMO/31739
フルテキストURL fulltext.pdf
著者 Takaki, Miyako| Neya, Toshiaki| Nakayama, Sosogu|
抄録 <p>The role of the lumbar sympathetic nerves and supraspinal mechanism in the defecation reflex was investigated in 30 adult cats and 6 kittens. One or two propulsive contractions, whose mean pressure evoked was more than about 90 cmH2O (adult cats) and 50 cmH2O (kittens), were induced in the rectum of all animals by rectal distension. These propulsive contractions could be generated at the descending and the transverse colons. The removal of the supraspinal influence by spinal transection at T13 or removal of pelvic afferents to the supraspinal center by spinal transection at L abolished the propulsive contractions. Successive lumbar sympathectomy restored the contractions. Lumbar sympathectomy and the successive removal of the supraspinal influence did not affect the propulsive contractions. In both cases, the final exclusion of the sacral segments by pithing of the spinal cord abolished the propulsive contractions. These results suggest that the sacral excitatory reflex mediated via pelvic nerves and the lumbar inhibitory reflex mediated via lumbar sympathetic nerves can function during rectal distension in spinal cats and that the lumbar inhibitory reflex is suppressed by the supraspinal sympathetic inhibitory reflex activated by pelvic afferents in intact cats, as in guinea pigs, resulting in propulsive contractions.</p>
キーワード lumbar sympathectomy defecation reflex cats rectal distension
Amo Type Article
発行日 1987-12
出版物タイトル Acta Medica Okayama
41巻
6号
出版者 Okayama University Medical School
開始ページ 249
終了ページ 257
ISSN 0386-300X
NCID AA00508441
資料タイプ 学術雑誌論文
言語 English
論文のバージョン publisher
査読 有り
PubMed ID 3439480
Web of Sience KeyUT A1987L530300003
JaLCDOI 10.18926/AMO/31611
フルテキストURL fulltext.pdf
著者 Zhao, Dan Dan| Namba, Taketoshi| Araki, Junichi| Ishioka, Kazunari| Takaki, Miyako| Suga, Hiroyuki|
抄録 <p>Nipradilol (3,4-dihydro-8-(2-hydroxy-3-isopropylamino) propoxy-3-nitroxy-2H-1-benzopyran) is a newly synthesized chemical agent designed to possess beta-adrenoceptor blocking and vasodilating actions. Nipradilol decreased left ventricular contractility index (Emax, slope of the ventricular end-systolic pressure-volume relation), systolic pressure-volume area (PVA, a measure of ventricular total mechanical energy) and oxygen consumption in cross-circulated excised dog hearts. However, nipradilol did not decrease total coronary resistance. These results indicate that nipradilol, like propranolol, depresses myocardial mechanoenergetics and that the vasodilating action of nipradilol could not be detected in the present study.</p>
キーワード cardiac mechanics cardiac energetics coronary circulation vertricle ?-blocker
Amo Type Article
発行日 1993-02
出版物タイトル Acta Medica Okayama
47巻
1号
出版者 Okayama University Medical School
開始ページ 29
終了ページ 33
ISSN 0386-300X
NCID AA00508441
資料タイプ 学術雑誌論文
言語 English
論文のバージョン publisher
査読 有り
PubMed ID 8096354
Web of Sience KeyUT A1993KP18500005
JaLCDOI 10.18926/AMO/31256
フルテキストURL fulltext.pdf
著者 Neya, Toshiaki| Mizutani, Masatoshi| Takaki, Miyako| Nakayama, Sosogu|
抄録 <p>To investigate the action of motilin on the sphincter of Oddi, the flow rate of the perfusate (FRP) discharged into the duodenal lumen through the orifice of the common bile duct was measured by means of an electric drop counter in decerebrated dogs. Motilin in doses above 0.5 micrograms/kg i.v. reduced or stopped the FRP. The fifty percent recovery time of FRP was 20 min and full recovery time was 30 min. The reduction of FRP induced by motilin was unaffected by denervation and atropinization. These results suggest that motilin caused an increase in tone of the sphincter of Oddi by acting on the sphincter muscle.</p>
キーワード bile duct bile excretion choledocus motilin sphincter of Oddi.
Amo Type Brief Note
発行日 1981-12
出版物タイトル Acta Medica Okayama
35巻
6号
出版者 Okayama University Medical School
開始ページ 417
終了ページ 420
ISSN 0386-300X
NCID AA00508441
資料タイプ 学術雑誌論文
言語 English
論文のバージョン publisher
査読 有り
PubMed ID 6459713
Web of Sience KeyUT A1981MV25300005
JaLCDOI 10.18926/AMO/31027
フルテキストURL fulltext.pdf
著者 Jin, Ji-Guang| Neya, Toshiaki| Takaki, Miyako|
抄録 <p>To study the polarity of the efferent pathway of the myenteric plexus, recordings were made of the mechanical activity of the longitudinal muscle of isolated guinea-pig ileal segments upon stimulation with an electrical field around the myenteric plexus contained within strips of longitudinal muscle (LM-MP) continuous with each end of ileal segment. The amplitude of the contractile response to stimulation of the anal LM-MP was always larger than that to the oral LM-MP. After cholinergic and adrenergic transmission was suppressed by atropine (10 microM) and guanethidine (1 microM), and the tone of the segment was enhanced by histamine (1 microM), the LM-MP stimulation produced non-cholinergic, non-adrenergic (NCNA) ascending contraction and NCNA descending relaxation. The NCNA contraction, but not the NCNA relaxation, was abolished or reduced by desensitization to substance P. The present results suggest that the NCNA innervation of the myenteric plexus participates in the polar effects observed in the guinea-pig ileum, that the NCNA excitatory response may be mediated at least in part by myenteric substance P neurons, and that the NCNA inhibitory response is mediated by non-adrenergic neurons.</p>
キーワード ileal motility intrinsic reflex myenteric plexus substance P guinea pig
Amo Type Article
発行日 1988-06
出版物タイトル Acta Medica Okayama
42巻
3号
出版者 Okayama University Medical School
開始ページ 129
終了ページ 136
ISSN 0386-300X
NCID AA00508441
資料タイプ 学術雑誌論文
言語 English
論文のバージョン publisher
査読 有り
PubMed ID 2456670
Web of Sience KeyUT A1988P034000002
JaLCDOI 10.18926/AMO/30860
フルテキストURL fulltext.pdf
著者 Takaki, Miyako| Jin, Ji-Guang| Nakayama, Sosogu|
抄録 <p>Effects of capsaicin on the circular muscle motility of the isolated guinea-pig ileum were investigated. Capsaicin produced a contraction followed by a relaxation of the circular muscle. Both responses were easily desensitized. As the late relaxation response was not sufficiently intense to be analyzed, the inhibitory effect of capsaicin on substance P-induced contractions was explored. Capsaicin abolished the substance P-induced contractions. This inhibitory effect was not affected by tetrodotoxin, and the effect was desensitized. Therefore, all effects of capsaicin on circular muscle motility seem to be due to the release of sensory neuropeptides, similarly to those elicited in the longitudinal muscle.</p>
キーワード calcitonin gene-related peptide capsaicin circular muscle intestine substance P
Amo Type Article
発行日 1989-12
出版物タイトル Acta Medica Okayama
43巻
6号
出版者 Okayama University Medical School
開始ページ 353
終了ページ 357
ISSN 0386-300X
NCID AA00508441
資料タイプ 学術雑誌論文
言語 English
論文のバージョン publisher
査読 有り
PubMed ID 2483022
Web of Sience KeyUT A1989CG27400006
JaLCDOI 10.18926/AMO/30461
フルテキストURL fulltext.pdf
著者 Takaki, Miyako| Jin, Ji-Guang| Nakayama, Sosogu|
抄録 <p>Capsaicin-sensitive and hexamethonium-insensitive contractile and relaxatory motor responses of circular muscle induced by mesenteric nerve stimulation were studied. Desensitization to substance P or to neurokinin A, or the substance P antagonist, spantide largely reduced the initial contractile response. Desensitization to calcitonin gene-related peptide moderately reduced the late prolonged relaxation response. These results indicate that both responses of the circular muscle to mesenteric nerve stimulation may be attributed to a release of neuropeptides evoked by the 'efferent' stimulation of capsaicin-sensitive sensory nerves.</p>
キーワード calcitonin gene-relatsd peptide capsaicin ileal motility mesenteric nerve substance P
Amo Type Article
発行日 1990-06
出版物タイトル Acta Medica Okayama
44巻
3号
出版者 Okayama University Medical School
開始ページ 135
終了ページ 139
ISSN 0386-300X
NCID AA00508441
資料タイプ 学術雑誌論文
言語 English
論文のバージョン publisher
査読 有り
PubMed ID 1696423
Web of Sience KeyUT A1990DM18300004
JaLCDOI 10.18926/AMO/30450
フルテキストURL fulltext.pdf
著者 Takaki, Miyako| Nakayama, Sosogu|
抄録 <p>Effects of mesenteric nerve (MN) stimulation on the electrophysiological behavior of myenteric neurons in the guinea pig ileum were investigated with intracellular recording techniques in the myenteric flaps innervated with mesenteric nerves. MN stimulation at 0.11-6 Hz evoked fast excitatory postsynaptic potentials (EPSPs) in 6 myenteric neurons (2 Type 2/AH, 3 NS and 1 Type 1/S cells) and rarely evoked antidromic soma spike potentials in 3 myenteric neurons. Fast EPSPs were abolished by hexamethonium. Slow EPSPs evoked by MN stimulation (Takaki and Nakayama (1988) Brain Res., 442, 351-353) were also obtained in 5 Type 2/AH neurons and were irreversibly abolished by superfusion with capsaicin 10 microM. It is, therefore, likely that fast EPSPs mediated by nicotinic cholinergic receptors are due to stimulation of the vagus nerve and slow EPSPs are mediated by a release of substance P at axosomatic synapses due to antidromic activation of the capsaicin-sensitive sensory nerves.</p>
キーワード autonomic ganglion intestine mesenteric nerve (MN) stimulation myenteric neuron
Amo Type Article
発行日 1990-10
出版物タイトル Acta Medica Okayama
44巻
5号
出版者 Okayama University Medical School
開始ページ 257
終了ページ 261
ISSN 0386-300X
NCID AA00508441
資料タイプ 学術雑誌論文
言語 English
論文のバージョン publisher
査読 有り
PubMed ID 1701955
Web of Sience KeyUT A1990EG00700004
JaLCDOI 10.18926/AMO/30444
フルテキストURL fulltext.pdf
著者 Takaki, Miyako| Mizutani, Masatoshi| Jin, Ji-Guang| Nakayama, Sosogu|
抄録 <p>In the present study, tryptamine produced a slow hyperpolarization in a few neurons other than a slow depolarization in myenteric neurons of the isolated guinea-pig ileum. Neither the adrenergic neuron blocker, guanethidine nor the 5-hydroxytryptamine uptake inhibitor, zimelidine, which can inhibit the release of 5-hydroxytryptamine from enteric neurites induced by tryptamine (M. Takaki et al. (1985) Neuroscience 16, 223-240), affected this slow hyperpolarization. Therefore, it was concluded that the slow hyperpolarization induced by tryptamine in myenteric neurons was not mediated via the release of 5-hydroxytryptamine or noradrenaline. It might be possible that the hyperpolarization was induced by a direct action of tryptamine on myenteric neurons per se.</p>
キーワード intracelluar recording tryptamine hyperpolarization myenteric neurons
Amo Type Article
発行日 1990-04
出版物タイトル Acta Medica Okayama
44巻
2号
出版者 Okayama University Medical School
開始ページ 87
終了ページ 91
ISSN 0386-300X
NCID AA00508441
資料タイプ 学術雑誌論文
言語 English
論文のバージョン publisher
査読 有り
PubMed ID 2141967
Web of Sience KeyUT A1990DE10000005
JaLCDOI 10.18926/AMO/30367
フルテキストURL fulltext.pdf
著者 Neya, Toshiaki| Takaki, Miyako| Nakayama, Sosogu|
抄録 <p>In guinea pigs whose pelvic nerves were bilaterally sectioned, afferent stimulation of rectoanal branches of the pelvic nerve (PAS) could produce an intense contraction in the rectum similar to propulsive contractions elicited during defecation. The mechanism of this reflex was analyzed. Rectal contraction by PAS was abolished after transecting the spinal cord at T13 or sectioning the lumbar splanchnic nerves (LSN) or lumbar colonic nerves (LCN), but was unaffected by severing the intermesenteric and hypogastric nerves. Rectal contraction induced by PAS was abolished peripherally by atropine, guanethidine or yohimbine, while propranolol had no affect. Yohimbine antagonized the inhibitory effect of LSN or LCN stimulation on atropine-sensitive rectal contractions. It may, therefore, be concluded that PAS blocks the inhibition, by LCN efferents acting through alpha-adrenoreceptors, of cholinergic neurons in the myenteric plexus, thus facilitating recto-rectal propulsive contractions initiated by the defecation reflex.</p>
キーワード intestine rectal motility enteric nerves automic nerves defecation
Amo Type Article
発行日 1984-02
出版物タイトル Acta Medica Okayama
38巻
1号
出版者 Okayama University Medical School
開始ページ 21
終了ページ 27
ISSN 0386-300X
NCID AA00508441
資料タイプ 学術雑誌論文
言語 English
論文のバージョン publisher
査読 有り
PubMed ID 6702482
Web of Sience KeyUT A1984SF03000003