巻号一覧
33 巻, 1 号
選択された号の論文の13件中1～13を表示しています
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河田 溥, 大場 三栄, 波多江 純真, 岸 美惠子1983 年 33 巻 1 号 p. 1-17
発行日: 1983年
公開日: 2006/07/28
ジャーナル フリーLanthanum of 0.1 to 0.2mM caused a twitch inhibition and further showed a marked, long-lasting twitch potentiation during washout in both ventricular strips of bullfrog and atrial or papillary muscles of guinea-pig. It was found that the effect was more conspicuous in the frog heart. A similar potentiation was observed by applying gadolinium instead of lanthanum. The participation of endogeneous catecholamine release is unlikely since the positive inotropic effect was never affected by the presence of β-adrenergic blocker. The potentiation was not accompanied by any increase in the action potential plateau, suggesting independence of the phenomenon on the calcium current. A marked elevation of the resting tension was produced during a long-term lanthanum perfusion, reflecting the increase in the intracellular calcium level. On the other hand, transient increase in the resting tension was frequently observed on returning to normal Ringer solution. The latter change seemed to result from a transient increase in the resting permeability to calcium ions. The negative or positive inotropic effect by increasing or lowering the external sodium concentration observed under the control condition was strongly depressed during the twitch potentiation. In addition, sodium-free contracture induced by solutions isotonically replaced with sucrose or potassium chloride was augmented both during lanthanum perfusion and during its washout. These results suggest the possibility that the elevation of the intracellular calcium level due to inhibition of Na-Ca exchange mechanism and/or increase in the calcium permeability is the principal cause for the twitch potentiation caused by lanthanum washout.抄録全体を表示PDF形式でダウンロード (1244K) -
成瀬 昭二, 高田 宗春, 肥塚 泉, 亘 弘1983 年 33 巻 1 号 p. 19-28
発行日: 1983年
公開日: 2006/07/28
ジャーナル フリーSequential metabolic changes in rat brain were monitored by in vivo measurements of 31P NMR spectra using a topical magnetic resonance (TMR) spectrometer, during the course of experimentally induced cerebral infarction and also during recovery produced by restoration of circulation.
The experimental cerebral infarction was rendered by a slightly modified version of the method of Pulsinelli and Brierley (1979). The bilateral coagulation of the vertebral arteries at the level of alar foramina of the first cervical vertebra (preinfarction) did not show any change in NMR spectrum, but the subsequent bilateral ligation of internal carotid arteries produced a decrease in the peaks of ATP and phosphocreatine and a concomitant increase in the peak of inorganic phosphate within a few minutes. Intracellular pH, calculated from the chemical shift of inorganic phosphate, declined. These changes became maximal at approximately 30min after the infarction. Reinstatement of blood flow to the cerebrum, produced by untying the ligature of internal carotid arteries, resulted in an immediate restoration of the peaks of ATP and phosphocreatine, which was followed by a reduction in the peak of inorganic phosphate within a few minutes. The spectrum recovered to its preinfarction pattern about 30min after the restoration of the circulation. These experiments demonstrate that phosphorus compounds change very rapidly during infarction, and that these changes were reversible at least during a 30min period.抄録全体を表示PDF形式でダウンロード (784K) -
桑原 厚和1983 年 33 巻 1 号 p. 29-40
発行日: 1983年
公開日: 2006/07/28
ジャーナル フリーThe effects of chemical and mechanical stimulations on gastric motility was studied in 19 anesthetized dogs by using electro-myographical techniques. The animals were fasted for 18hr or more before each experiment. Six or eight bipolar silver-wire electrodes were implanted on a gastric wall serially from the fundus to the terminal antrum. At the pre-stimulation stage, the periodic simple electrical activity, which is called electrical control activity (ECA), was regularly recorded from the corpus to the antrum of the stomach; the frequency of which was 4.5±0.5cycles/min on the average. Mechanical stimulation (distention of the stomach) decreased the ECA frequency depending on the degree of distention. The ECA frequency was decreased to 2.9±0.4 cycles/min by the 400ml distention. Chemical stimulations to the gastric antral mucosa also decreased the ECA frequency depending on the strength of acidity or alkalinity. The instillation of a solution of pH 1 or 12.5 into the stomach decreased the ECA frequency to 3.4±0.7, and 3.5±0.5cycles/min, respectively. A stronger alkaline solution induced anti-peristaltic discharges in 4 of 6 cases. The results indicate that both mechanical and chemical stimulations decrease the ECA frequency depending on stimulus strength.抄録全体を表示PDF形式でダウンロード (844K) -
入内島 十郎1983 年 33 巻 1 号 p. 41-50
発行日: 1983年
公開日: 2006/07/28
ジャーナル フリーIn spontaneously hypertensive and normal control rats in the conscious state, blood flow was observed in the carotid artery, superior mesenteric artery, renal artery, and terminal aorta with a chronically implanted electromagnetic flow probe. At rest, flow per body weight was not different between the two groups except at the terminal aorta where it was significantly smaller in hypertensive rats (P<0.05). Regional peripheral resistance was higher in hypertensive rats than in normal rats in all the four arteries, but its elevation in the former was not uniform but most marked in the hindquarter area supplied by the terminal aorta. Quantitatively, this area was estimated to contribute about 40% of the total conductance decrease in hypertensive rats in comparison with the control. This suggests the importance of elevation of resistance in muscle blood vessels in hypertension. The contributions from the superior mesenteric area and the bilateral kidneys were estimated to be about 15% each. In the transposition response induced by transposing rats from their home cage to a new cage, the increase in hindquarter flow was significantly greater in hypertensive rats than in normal rats (P<0.01). The sum of the mean flows of the four arteries, a measure of cardiac output, was not different between hypertensive and normal rats at rest but greater in the former during transposition response. Elevation of arterial pressure in the response in hypertensive rats but not in the normal rats was ascribable largely to a greater increase in cardiac output in the former than the latter.抄録全体を表示PDF形式でダウンロード (782K) -
長 琢朗, 小笠原 利保, 加藤 誠志1983 年 33 巻 1 号 p. 51-57
発行日: 1983年
公開日: 2006/07/28
ジャーナル フリーIn order to find out the changes in myometrial properties towards parturition, effects of Mg, oxytocin, and prostaglandin F2α (PGF2α) were investigated on longitudinal muscle strips taken from rat uteri on Days 20 and 22 of pregnancy. With intracellular recording by microelectrode, membrane potential was 50.5±1.4mV on Day 20, and 49.9±1.0mV on Day 22 in the Mg-free Krebs solution. The slow potential was larger, and the spike potentials during a burst discharge exhibited variable amplitude on Day 20, whereas these were regular on Day 22. With extracellular recording by the rubber gap method, spike potentials discharged in a synchronized manner on Day 22, suggesting a better coordination between cell groups. When 1.2mM Mg was applied, the spontaneous activity was depressed more strongly on Day 22. The excitatory effect of PGF2α faded sooner, whereas that of oxytocin persisted. When the fading of PGF2α had occurred, the excitatory effect of oxytocin was weaker than when it was given alone. Because propagation of spontaneous activity, occurring either in the Mg-free solution or in the presence of oxytocin and PGF2α in normal Krebs solution, did not show a definite direction from ovarian to vaginal side of the longitudinal muscle, it was concluded that generation of spontaneous activity was not localized in a given site of the muscle, but originated anywhere in Days 20 and 22 preparations.抄録全体を表示PDF形式でダウンロード (1356K) -
佐々木 貞雄, 中垣 育子, 森 博彦, 今井 雄介1983 年 33 巻 1 号 p. 69-83
発行日: 1983年
公開日: 2006/07/28
ジャーナル フリーElectron probe X-ray microanalysis using freshly frozen hydrated and dried thin sections of dog submandibular gland was performed to determine the distribution of elements and water in the acinar cells of resting and stimulating states. The results obtained are as follows : (a) The secretory granules contained high concentrations of Ca and S while high concentrations of K and P were present in the cytoplasm and/or nucleus of acinar mucous cells of the gland in the resting state. (b) With pilocarpine stimulation, the concentration of Ca increased in the cytoplasm and decreased in the secretory granules, while there was an increase in the concentration of Na and Cl in both the cytoplasm and secretory granules of the cells. (c) The local dry-mass fractions of acinar cells, estimated by comparing the continuum radiation of X-ray spectrum from the frozen hydrated sections with that from the frozen dehydrated sections, were approximately 20 and 33% in the cytoplasm and secretory granules of resting acinar cells, respectively, and each value was not significantly altered under conditions of stimulation having a tendency to decrease slightly. Therefore, the passive Na and Cl influx and the cytoplasmic Ca flowed in from extracellular spaces and released from secretory granules, an intracellular calcium store, by secretory stimulation probably triggers the passive or active Na and CL extrusion and consequently the osmotic water flux from the basal part of acinar cells to the secretory granules and the lumen, as well as the serial exocytosis of the granules in the luminal side of the acinar cells.抄録全体を表示PDF形式でダウンロード (2614K) -
広田 秋彦, 藤井 志郎, 酒井 哲郎, 神野 耕太郎1983 年 33 巻 1 号 p. 85-100
発行日: 1983年
公開日: 2006/07/28
ジャーナル フリーThe effects of temperature on spontaneous action potential activity in the 7-9 somite embryonic precontractile chick hearts were investigated using an optical method for monitoring membrane potential. A potential-sensitive merocyanine-rhodanine dye was used as an optical probe. Cooling caused a marked decrease in the frequency of occurrence of the spontaneous action potential. This slowing was associated with a decreased rate of diastolic depolarization of the pacemaker action potential. When the temperature was lowered, a decrease in the rate of rise and a prolongation of duration of the optical action signal also occurre. In addition, cooling resulted in a disordering of the rhythmicity of the action potential, and a decrease in the conduction velocity of excitation. Q10 values for such parameters were calculated: there were slight decreases in the Q10 values for the frequency and conduction velocity for 7-9 somite embryonic hearts.抄録全体を表示PDF形式でダウンロード (1163K) -
Tibor TÓTH, 中浜 博, 嶋 啓節, 山本 光璋, 綾 皓二郎1983 年 33 巻 1 号 p. 101-113
発行日: 1983年
公開日: 2006/07/28
ジャーナル フリーUsing the concept of the Markov dependency, we analyzed the spontaneous activity in the pre- and postganglionic nerve trunks of the feline superior cervical ganglion. The time structure (order and value of time dependency) of the sequence of compound action potentials was determined The analysis revealed that the time dependency of the postganglionic activity is of higher order and is generally more consistent than that of the preganglionic one. The difference in orders and values between the pre- and postganglionic activities was found to be a measure of the integrative function of the ganglion. A transformation by the ganglion of some additional information, inaccessible in the time structure of the preganglionic activity, seems to underlie this difference.抄録全体を表示PDF形式でダウンロード (937K) -
河原 克雅, 坂井 建雄, 星 猛1983 年 33 巻 1 号 p. 115-127
発行日: 1983年
公開日: 2006/07/28
ジャーナル フリーTransmural electrical potential difference (PD) of the newt ureter was measured with glass microelectrodes and its nature was studied pharmacologically or by ion replacement experiments. The PD in the presence of standard Ringer solution on both sides averaged -76.0±1.3 mV, lumen negative. The magnitude of the PD depended on the Na+ concentration of the luminal fluid; the PD increased in a saturable way with increase in the Na+ concentration. Amiloride added to the luminal fluid at 10-4M greatly reduced the PD and increased the transmural resistance. The half maximum inhibition was seen at 2.6×10-6M and the maximum inhibition at 10-4M where the PD reduced to 3.8% of control. Amiloride added to the external medium at 10-4M had no effect on both the PD and the resistance. Ouabain added to the external medium at 10-3M caused a gradual decrease in the PD, which fell to 36% of its initial value after 60min. The specific transmural resistance (Rt) was estimated by recording spatially decaying electrotonic potentials along the ureter and applying cable analysis. The short-circuit current (Isc) was calculated from the PD and the Rt. The Rt and the Isc averaged 31.7±7.7kΩ•cm2 and 3.9± 1.5μA•cm-2, respectively. The results indicate that the epithelial cells of the newt ureter have amiloride-sensitive Na+ channels at the luminal membrane and are transporting Na+ actively, like epithelia of the urinary bladder and the skin of amphibia.抄録全体を表示PDF形式でダウンロード (1011K) -
上江洲 栄子, 松本 淳治1983 年 33 巻 1 号 p. 129-133
発行日: 1983年
公開日: 2006/07/28
ジャーナル フリーIntraventricular administration of actinomycin D and actinomycin S3, inhibitors of RNA synthesis, did not suppress paradoxical sleep (PS), but actinomycin S3 increased PS and deep slow wave sleep (DS) in the dark period (18:00-06:00), suggesting that RNA synthesis plays a role in the decrease of DS and PS in the dark period of circadian rhythm.抄録全体を表示PDF形式でダウンロード (378K) -
今村 一之, 小野田 法彦1983 年 33 巻 1 号 p. 135-138
発行日: 1983年
公開日: 2006/07/28
ジャーナル フリーWe developed a simple method, a pre-event cumulative sum chart, which could visually display a change in the discharge rate which occurred at every stimulation. The statistical significance was visually inspected by critical lines on each chart. This study presented examples of neocortical response to odors.抄録全体を表示PDF形式でダウンロード (252K) -
堀田 健, 山本 喜通, 今井田 克己, 大島 正人, 福島 正治, 伊東 信行1983 年 33 巻 1 号 p. 139-143
発行日: 1983年
公開日: 2006/07/28
ジャーナル フリーRat urinary bladder epithelial cells exhibited a membrane potential of about -22 (apical) and -24 (basal) mV in normal Krebs solution. Blockade of Na+ entry through the apical membrane by Na+ depletion or administration of amiloride, or inactivation of the Na pump in the basal membrane by ouabain resulted in marked hyperpolarization of the epithelial cells. N-butyl-N-(4-hydroxybutyl) nitrosamine (BBN), a specific carcinogen, and saccharin, a potent enhancer of carcinogenesis, inhibited development of the Na+ channel and/or Na pump on the bladder epithelium. This physiology may contribute to the abnormal intracellular environment leading to bladder carcinoma.抄録全体を表示PDF形式でダウンロード (336K) -
佐治 眞理, 三浦 光彦1983 年 33 巻 1 号 p. 145-149
発行日: 1983年
公開日: 2006/07/28
ジャーナル フリーFollowing the application of angiotensin II to cultured lower brain stem neurons of rat embryos, the facilitatory response was mostly seen in small-sized oval, fusiform, and polygonal neurons, while the inhibitory response was seen in medium-sized pyramidal and multipolar neurons. Saralasin blocked both facilitatory and slow inhibitory responses, but had no effect on the fast inhibitory response.抄録全体を表示PDF形式でダウンロード (340K)
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