巻号一覧
29 巻, 5 号
選択された号の論文の11件中1～11を表示しています
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永井 寅男, 高氏 昌, 小坂 功, 筒浦 理正1979 年 29 巻 5 号 p. 539-549
発行日: 1979年
公開日: 2011/06/07
ジャーナル フリーThe time course of the inhibition of peak tension (inactivation) of potassium contracture induced by conditioning depolarization with 10, 15, 20 and 30 mm K+ was examined, using single twitch fibers from the frog semitendinosus muscle. The time-dependence curve of the inactivation was biphasic, consisting of the first phase and the second phase. The first phase was characterized as follows: 1) the time course and the extent depend on the degree of conditioning depolarization; 2) the inactivation proceeds exponentially and finally reaches a steady level; and 3) the rate is markedly increased by lowering Ca2+ in the external medium. It could be considered that the first phase of the inactivation is an analogical phenomenon with the inactivation of sodium conductance in a squid giant axon. The second phase of the inactivation induced by conditioning with 20 and 30 mm KK+ reached its full inactivation independently of the degree of conditioning depolarization. On the basis of these results, the terms inactivation 1 and inactivation 2 were given to the first phase and second phase, respectively, of the time-dependence curve of the inactivation of potassium contracture. We have抄録全体を表示PDF形式でダウンロード (984K) -
入来 正躬, 古沢 恵美, P.I. KORNER, P.K. DORWARD1979 年 29 巻 5 号 p. 551-558
発行日: 1979年
公開日: 2011/06/07
ジャーナル フリー1. The effects of changing intravascular pressures on integrated ear sympathetic nerve activity (ESNA) were studied in anesthetized artificially ventilated rabbits by inflating aortic and inferior vena caval perivascular balloons under conditions of normal arterial PO2 and during arterial hypoxia.
2. At normal PO2 ESNA was unaffected by arterial and cardiopulmonary baroreflex influences. The small inhibition of ESNA observed during rises in arterial pressure after vagotomy was also present after section of the carotid sinus and aortic nerves, and after cutting both vagi as well.
3. During hypoxia there was marked inhibition of ESNA, which was minimally influenced by vagotomy but abolished by section of the carotid sinus and aortic nerves, suggesting that it was chemoreceptormediated. There was a pressure-related rise in ESNA which was abolished by vagotomy and considered to be due to a central nervous chemoreceptor-cardiopulmonary baroreflex interaction.抄録全体を表示PDF形式でダウンロード (857K) -
森本 武利, 白木 啓三, 三木 健寿, 田中 義文1979 年 29 巻 5 号 p. 559-567
発行日: 1979年
公開日: 2011/06/07
ジャーナル フリーRadioiodinated albumin was injected into the subcutaneoustissue of the thigh of human subjects and its disappearance rate fromthe injection site and the blood levels of the tracer were comparedbetween exercise loaded, heat loaded experiments and the controlutilizing two-compartment analysis. The time course of radioactivityin the blood was expressed as the equation p(t)=A (e-αt- e-βt) . In theexercise experiment, the half-time of β and the time required to reachthe maximum level was significantly shorter than in the heat experimentand in the controls. The decay of radioactivity at the injection site wasset to the equation s (t)=Be-γt+Ce-δtby the least square method.The value of γ, which had a half-time of about 24 hr, was significantlyshorter in the exercise than in the control experiments. From theseresults, it was concluded that the rate of mobilization of subcutaneousprotein via lymph flow is faster under an exercise load than the control, and that the rate under heat load does not deviate from controlexperiments.抄録全体を表示PDF形式でダウンロード (879K) -
堀内 噎子, 林 秀生1979 年 29 巻 5 号 p. 569-583
発行日: 1979年
公開日: 2011/06/07
ジャーナル フリーIn order to examine the pH dependency of Cd effects on cardiac muscle, the electrical and mechanical activities in the bullfrog heart were investigated in relation to various external pHs and concentrations of Cd. The amplitude and duration of the action potential or the spontaneously beating frequency in the atrium were not significantly affected during the 3-min administration of various concentrations of Cd in a range from pH 6 to 10, but the isotonic contraction at the end of the same period was greatly altered: the lower the external pH the more Cd decreased the contractility of the atrium. This pH dependency of Cd effects was also observed in SO4-Ringer's solution whose anions, SO4, were more impermeable than Cl. Decrease in contractility in Cd- Ringer's solution was counteracted by excess Ca. The lower the pH of the Cd-Ringer's solution, the more Ca was necessary to counteract an equal amount of Cd. The amount of Cd-uptake into the atrium was analyzed after soaking the atrium in various concentrations of Cd-Ringer's solution. The higher the concentration of external Cd, the larger the Cd-uptake into the atrium. No pH dependency, however, was observed in this relationship. This suggests that probably only a small fraction of total Cd-uptake interacts with Ca-binding sites which is specific to contraction, and causes the Cd-induced decrease in contractility. This process is considered to be pH-dependent. However, most Cd-uptake into cardiac muscle is pH-independent and may be nonspecific to contraction.抄録全体を表示PDF形式でダウンロード (1628K) -
坂田 義行1979 年 29 巻 5 号 p. 585-596
発行日: 1979年
公開日: 2011/06/07
ジャーナル フリーEffects of intravenously injected endogenous pyrogen on the unit activity of temperature-responsive neurones (TR neurones) of medulla oblongata were investigated in urethanized rabbits with an intact or lesioned preoptic/anterior hypothalamic area (PO/AH). TR neurones of the medulla responded to p yrogen in the same manner as did those of the PO/AH; the firing rate in the warm-responsive neurones were depressed and the cold-responsive neurones augmented. However, one-fourth of the medullary TR neurones did not respond to pyrogen in the PO/AH intact group (the control group). Following lesion of the PO/AH, the relative frequencies of TR neurones affected by pyrogen decreased as compared with those in control, and such was suggested to be more apparent in TR neurones discharging at rates of 10 imp./sec or more. Effects of the PO/AH-lesion were also seen in that the magnitude of the facilitatory or inhibitory effect of pyrogen was reduced in the PO/AH-lesioned group as compared with the control group. In some TR neurones an antipyretic agent (Sulpyrine, 48-151 mg/kg) was found to abolish responses to pyrogen.抄録全体を表示PDF形式でダウンロード (1132K) -
中井 正継, 田村 俊世, 神谷 瞭, 戸川 達男1979 年 29 巻 5 号 p. 597-608
発行日: 1979年
公開日: 2011/06/07
ジャーナル フリーThe intrasinusoidal flow pattern of blood drained from the hepatic arterial and portal venous routes was studied with and without stimulation of the hepatic nerves. This flow pattern was evaluated in terms of a relationship between hepatic arterial flow fraction of total flow and its transit time volume fraction of total blood volume of the liver. The transit time volume of the hepatic artery is defined by the product of flow and mean transit time through the hepatic arterial system. These fractions were determined by adopting a recently proposed principle of the indicator dilution technique-a double injection-single sampling site method. The hepatic arterial flow fraction in dog liver was adjusted at various levels by perfusing the hepatic artery with the animal's own blood drained from the femoral arteries. The resulting relationships between these two fractions showed linearity and a close resemblance to a line of identity over a wide range of the flow fraction both with or without stimulation. Two possible patterns of the blood flow in the sinusoids were discussed for an evaluation of these results. First, intrasinusoidal mixing of both arterial and portal blood occurs in each sinusoid at any hepatic arterial flow fraction. Second, an increase in the hepatic arterial flow fraction may give rise to functionally, not anatomically, separate sinusoids only for arterial blood. The difference between the relationships with and without nerve stimulation was statistically insignificant. This evidence implies that there is no detectable effect of the hepatic nerves on the adjustment of the intrasinusoidal flow pattern of blood.抄録全体を表示PDF形式でダウンロード (1271K) -
河田 溥1979 年 29 巻 5 号 p. 609-625
発行日: 1979年
公開日: 2011/06/07
ジャーナル フリーThe effects of Na-free Li solution on the electrical and mechanical activities were examined in a bullfrog's ventricular strip. The action potential showed a triphasic change during Na-free perfusion: the initial decrease in the overshoot and duration, the secondary restoration and the gradual decrease in the membrane potential. The twitch contraction also changed in a triphasic manner: the initial rapid decrease with a transient development of contracture and the secondary slow decrease followed by a partial recovery. A negative staircase, which was accompanied by full-sized twitch contractions, was induced by lowering the stimulation rate in this medium, indicating an involvement of some intracellular Ca releasing sites for activating the well-maintained contractile proteins. When CaCl2 was omitted during Na-free Li perfusion the twitch decreased only slightly down to 71.8 % whereas in Na-containing medium it decreased to 11.9 %. The sensitivity of twitch to the external Ca was thus greatly diminished in the Na-free condition. A fairly large contracture could be elicited by high K solution in Ca-free Li solution even after a prolonged Ca-free perfusion. Modification of the action potential by passing a hyperpolarizing current did not affect the twitch occurring in the Li solution, in contrast to its marked effect on the muscle perfused with normal Ringer. From these results it is concluded that the twitch is activated mainly by Ca released from some intracellular site in the Na-free Li solution. The inhibitory effect of Mn on this contraction was discussed in relation to its intracellular action.抄録全体を表示PDF形式でダウンロード (1816K) -
溝西 任, 銭場 武彦1979 年 29 巻 5 号 p. 627-633
発行日: 1979年
公開日: 2011/06/07
ジャーナル フリーArterial and venous blood flow and oxygen saturation of the venous blood in the mesenteric vessels arising from single mesenteric artery and vein to the intestinal loop in anesthetized dogs were measured simultaneously with systemic arterial blood pressure during distension of this loop. Mesenteric arterial blood flow decreased to the zero level, while mesenteric venous outflow increased to about twice the quiescent level at the onset of elevation of intraluminal pressure. However, during distension, the decreased arterial blood flow tended to increase, but the increased venous flow was reduced to one half of the quiescent level. Oxygen saturation of venous blood diminished initially and then increased progressively during distension. At the end of distension venous outflow stopped temporarily. After suspension of distension, arterial and venous flow and oxygen saturation increased beyond the quiescent level. These results may suggest that there is a by-pass or A-V anastomosis which cannot be compressed mechanically by elevation of intraluminal pressure.抄録全体を表示PDF形式でダウンロード (742K) -
広田 秋彦, 藤井 志郎, 神野 耕太郎1979 年 29 巻 5 号 p. 635-639
発行日: 1979年
公開日: 2011/06/07
ジャーナル フリーUsing an optical method for measuring membrane potential, we monitored spontaneous action potential activity in the embryonic chick heart at the very early developmental stages, and found that spontaneous electrical activity was present at the developmental stage of 8 somites before the initiation of the heartbeat.抄録全体を表示PDF形式でダウンロード (541K) -
倉橋 昌司, 黒島 晨汎1979 年 29 巻 5 号 p. 641-644
発行日: 1979年
公開日: 2011/06/07
ジャーナル フリーProlonged noradrenaline treatment did not affect the urinary creatine excretion, creatine radioactivity, and the creatine contents of all muscles studied. Radioactive creatine uptake by skeletal muscle was significantly lower in noradrenaline-treated rats than in controls, while those by heart and diaphragm were not affected by noradrenaline.抄録全体を表示PDF形式でダウンロード (408K) -
有藤 平八郎, 高木 貞敬1979 年 29 巻 5 号 p. 645-649
発行日: 1979年
公開日: 2011/06/07
ジャーナル フリーResponses of 50 olfactory bulb neurons of the bullfrog to odorous solutions of ethyl n-butyrate were composed mainly of facilitation, inhibition and no response, whereas those of the same neurons to water were mainly of facilitation and delayed facilitation. The responses to water tended to continue longer than those to the odorous solutions.抄録全体を表示PDF形式でダウンロード (458K)
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