巻号一覧
32 巻, 4 号
選択された号の論文の17件中1～17を表示しています
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高氏 昌, 筒浦 理正, 永井 寅男1982 年 32 巻 4 号 p. 493-504
発行日: 1982年
公開日: 2011/06/07
ジャーナル フリーThe dependence of the occurrence of biphasic contractures on potassium chloride concentration, and the activation curve, the inactivation curve and the time-dependence curve of inactivation of the initial component of potassium contracture and those curves of the secondary component were examined, using single twitch fibers of the frog semitendinosus muscles. When single fibers having diameters of about 75-100 μm were used, typical biphasic contractures were clearly observed at 70-80 mM K. At 100 mM K the initial component was difficult to distinguish from the secondary component because of the fusion of both components, and at 60 and 40 mM K the initial component hardly occurred and the secondary component alone was observed. The threshold of the activation curve of the initial component (about 50-60 mM K) was higher than that of the secondary component (about 32 mM K) and also the time course of the inactivation, induced by conditioning depolarization, of the initial component did not coincide with that of the secondary component. From these results, it was concluded that the activation and inactivation processes of the excitation-contraction coupling of the initial component is different from those of the secondary component and that the efficiency of the coupling of the initial component is less than that of the secondary component. In addition, it was also indicated that each time-dependence curve of the inactivation of the initial and secondary components is biphasic, consisting of the first phase and the second phase, and that these phases have the characteristics of inactivation 1 and inactivation 2, respectively, which was proposed by us.抄録全体を表示PDF形式でダウンロード (1298K) -
Ichiji TASAKI, Kunihiko IWASA1982 年 32 巻 4 号 p. 505-518
発行日: 1982年
公開日: 2011/06/07
ジャーナル フリーMechanical changes in the squid giant axon associated with the production of an action potential are examined further by using piezoelectric and optical methods. The peak of swelling of the axon coincides with the peak of the action potential recorded internally at the site of mechanical recording. Mechanical changes produced by a train of action potentials do not summate. Repetitively fired action potentials induced by lowering the external Ca-ion concentration are preceded by a gradual swelling of the axon. An inward current through the membrane causes shrinkage and an outward current produces swelling of the axon. An inward current enhances and an outward current depresses the mechanical changes associated with the action potential. There is a transient shortening followed by an elongation of the axon when an action potential travels along the axon. It is argued that the experimental results obtained are consistent with the colloid chemical, or macromolecular, theory of excitation.抄録全体を表示PDF形式でダウンロード (1618K) -
柴田 裕行, 布村 忠弘, 永坂 鉄夫1982 年 32 巻 4 号 p. 519-527
発行日: 1982年
公開日: 2011/06/07
ジャーナル フリーThe metabolic response of warm-acclimated (25°C for 4 weeks) and cold-acclimated (5°C for 4 weeks) rats to infused norepinephrine (NE)(0.5-4μg/(kg·min)) was measured at an ambient temperature of 13°C, either before or after sinoaortic denervation. In warm-acclimated rats, vigorous shivering consistently occurring at 13°C was greatly inhibited by NE in a dose of 2-4μg/(kg·min). After sinoaortic denervation, no such inhibition of shivering was observed. In cold-acclimated rats, NE did not suppress but increased heat production at this temperature, no visible shivering being noticed. Phenylephrine, an a-adrenergic stimulant, increased blood pressure and decreased heart rate to the same extent in both groups of rats at this temperature. NE suppressed heat production even in cold-acclimated rats at -5°C, where the animals exhibited shivering. These results indicate that NE infusion inhibits shivering via the sinoaortic baroreceptor reflex, in both warm-acclimated and cold-acclimated rats. The non-occurrence of metabolic suppression in cold-acclimated rats after norepinephrine infusion in the 13°C environment may be due to an absence of shivering which is suppressed at this temperature.抄録全体を表示PDF形式でダウンロード (844K) -
Jesús G. NINOMIYA, Dieter MASCHER1982 年 32 巻 4 号 p. 529-539
発行日: 1982年
公開日: 2011/06/07
ジャーナル フリーWe investigated changes in membrane potential after small transections (2-4 mm) of the striated muscle of the guinea-pig cremaster and the rate of penetration of procion yellow (1-5 mg/ml) into the injured fibers. Transverse severance of the striated muscle fibers was followed by a marked drop of the membrane potential near the site of injury, such a fall being undetectable about 2 mm from the lesion. The depolarization reached a peak value (40 mV at 0.5 mm from the lesion) 3-5 min after injury and was followed by a gradual repolarization which was complete in about 60 min. A second lesion evoked the same changes, but under conditions of a low calcium solution, there was no recovery in the potential. The rate of indicator penetration reached a peak value (20μm/min) when depolarization was near maximal, declined as the membrane repolarized and became negligible in about 50 min. Conversely, the transected striated muscle fibers of the guinea-pig diaphragm remained depolarized for more than 1 hr after injury. These observations suggest that the healing-over process is a property of the striated muscle fibers of the guinea-pig cremaster and may tentatively be ascribed to the development of a calcium-dependent diffusion barrier (of unknown nature) in the area of the injury.抄録全体を表示PDF形式でダウンロード (1217K) -
反町 勝, 西村 茂人1982 年 32 巻 4 号 p. 541-551
発行日: 1982年
公開日: 2011/06/07
ジャーナル フリーCat adrenal glands were retrogradely perfused in vitro with modified Locke's medium and the mechanism of catecholamine (CA) secretion induced by choline was investigated. Choline-induced secretion of CA was accompanied by release of dopamine-β-hydroxylase, but not bythat of phenylethanolamine-N-methyl transferase, indicating that an exocytotic mechanism is involved in the secretion. Choline failed to induce the secretion of CA when Ca was absent from the perfusion solution.On the other hand, secretion increased when the concentration of Ca2+in the perfusion medium was raised to 10 mM. Stimulation of secretion by choline was observed from a concentration of 1 mM, and half-maximal secretion occurred at about 10 mM. The stimulatory action was weaker than that of acetylcholine (ACh); the effect of 100 mM chloine was approximately equal to that of 0.02 mM ACh. Secretion induced by a low concentration of choline was abolished by a nicotinic blocker, hexamethonium, while the response to choline at a concentration higher than 130 mM was only partially inhibited by cholinergic antagonists.The effects of choline and a low concentration of ACh were additive.On the other hand, 100 mM choline inhibited the response to a supramaximal concentration of ACh (0.5 mM), suggesting that ACh and choline stimulate the same nicotinic receptor. It is concluded that choline acts partially as a nicotinic agonist and that a concentration higher than 130 mM causes secretion by a mechanism additional to nicotinic receptor activation.抄録全体を表示PDF形式でダウンロード (1089K) -
伊藤 眞次, 広田 良二, 勝浦 五郎1982 年 32 巻 4 号 p. 553-560
発行日: 1982年
公開日: 2011/06/07
ジャーナル フリーIntraperitoneal (i.p.) injection of C-terminal octapeptide of cholecystokinin (CCK-8) produced a dose-related increase in plasma corticosterone levels in intact rats, but not in vagotomized ones. Intracerebroventricular (i.c.v.) injection of CCK-8 was ineffective in stimulating the secretion of corticosterone, and in vitro experiment on ACTH release indicated that CCK-8 could not affect pituitary tissue directly. Since i.p. injection of non-sulfated CCK-8 failed to elevate plasma corticosterone levels, sulfated tyrosine residue in the CCK molecule is assumed to be indispensable for the stimulation of visceral organs. On the other hand, vasoactive intestinal polypeptide (VIP) was found to cause a dosedependent increase in plasma corticosterone levels when administered centrally, but not after i.p. injection. However, VIP could not stimulate the release of ACTH from the pituitary tissue directly. The results suggest that VIP, but not CCK, stimulates the hypothalamic CRF neurons either directly or indirectly.抄録全体を表示PDF形式でダウンロード (793K) -
黒島 晨汎, 八幡 剛浩, 土居 勝彦, 大野 都美恵1982 年 32 巻 4 号 p. 561-571
発行日: 1982年
公開日: 2011/06/07
ジャーナル フリーSome endocrine and metabolic responses to acute cold and heat exposures were observed in rats acclimated to cold, heat, or both cold and heat. Rats exposed to both cold (12 hr, 5°C) and heat (12 hr, 34°C) for 4 to 5 weeks (CHA) showed less fall of colonic temperature (Tc in the cold 5°C) than heat-acclimated rats (34°C, 4 to 5 weeks)(HA) and warm controls (WC), but a greater fall than cold-acclimated rats (5°C, 4 to 5 weeks)(CA). CHA possessed a larger quantity of interscapular brown adipose tissue and showed greater cold-induced oxygen consumption (Vo2) than WC and HA but less than CA. Blood glycerol levels rose similarly in all groups in the cold, while the increase in blood free fatty acid (FFA) levels was significantly greater in HA and smaller in CA than in WC and CHA. Acute cold exposure caused the elevation of plasma glucagon level in WC and HA, but not in CA and CHA. It lowered plasma insulin levels in HA, and the insulin/glucagon molar ratio (I/G) in WC, HA, and CHA. All groups showed the same increases in Tc during acute heat exposure (34°C). However, the heat-induced increase in Vo2 was greater in WC than in HA, CA, and CHA. Blood metabolite levels were not affected by acute heat exposure in all groups. Plasma glucagon levels decreased in CHA, while plasma insulin levels increased in WC and CA. I/G increased in WC and CHA. These results indicate that thermal and metabolic responses would be modified by previous exposures to cold, heat, and cold-heat.抄録全体を表示PDF形式でダウンロード (1120K) -
後藤 昌義, 浦田 百美, 兵働 孝子1982 年 32 巻 4 号 p. 573-587
発行日: 1982年
公開日: 2011/06/07
ジャーナル フリーEffects of Ca-free or Na-deficient Ringer solution on the membrane currents of the bullfrog atrial muscle were studied using the double sucrose-gap method. Instantaneous outward current (Ik1) decreased in Ca-free and increased in Na-deficient conditions. The amplitude of nominal “fully activated delayed outward current” diminished under both sets of conditions. The diminution, however, was greater in Na-deficient medium (10 mm Na) and its activation curve shifted about 13.5 mV toward a more negative potential. In Ca-free Ringer, no such shift was observed, and the activation of the delayed outward current became slower and sigmoidal while the deactivation was faster than in the control. Contrarily, in Na-deficient Ringer, the activation became faster and exponential and the deactivation was slower. The current tail was composed of two exponentially declining components, and the slower, K-accumulation-related component (Ia) was suppressed in Ca-free and the faster component (Ixs) diminished in Na-deficient media. These findings may indicate that in the atrial muscle the instantaneous outward current is modified by a Na-Ca exchange mechanism and that the delayed outward current consists of two components, Ixs and Ia, which are susceptible to Na and Ca ions, respectively.抄録全体を表示PDF形式でダウンロード (1789K) -
George B. FRANK1982 年 32 巻 4 号 p. 589-608
発行日: 1982年
公開日: 2011/06/07
ジャーナル フリーWhen muscle fibres isolated from the frog's semitendinosus are placed in a calcium-free, bicarbonate buffered Ringer's solution the twitch declines in an irregular stepwise fashion and disappears usually within 1 to 9 min. There is often an initial period of twitch potentiation when the fibres are exposed to 0-Ca2+. Although considerably shorter than the time in 0-Ca2+ required to deplete intracellular calcium stores, the time required to eliminate the twitch is longer than estimates of the minimum time required to remove calcium from the fluid in the t-tubular network by free diffusion. When the calcium concentration was only partially reduced the twitch was potentiated at concentrations between 10 and 50% of the usual concentration in Ringer's. At lower calcium concentrations the potentiation is followed by a reduction, and in some fibres the twitch was eliminated without completely removing the calcium ions from the bathing solution. The results support the hypothesis that there is a store of calcium ions bound to the t-tubular membranes (“trigger calcium”) which is required for excitation-contraction coupling during the twitch.抄録全体を表示PDF形式でダウンロード (2254K) -
波多江 純真1982 年 32 巻 4 号 p. 609-625
発行日: 1982年
公開日: 2011/06/07
ジャーナル フリーThe effects of lanthanum on the resting membrane potential, action potential, membrane resistance, twitch tension, and potassium contracture were investigated and the localization of the drug was studied electron microscopically in isolated frog ventricular muscle. Lanthanum in concentrations of 0.2 to 5 mm decreased the resting potential by about 5-8 mV, which was accompanied by an increase in the membrane resistance of about 43% for the depolarizing and 40% for the hyperpolarizing direction. Lanthanum caused a decrease in height and a prominent shortening of the action potential, and also, a depression of the plateau level. In addition, it increased the threshold for action potential generation depending on its concentration. The slow response action potential was inhibited by lanthanum in parallel with twitch inhibition. This finding suggests that the twitch inhibition resulted from the suppression of the slow inward calcium current. In contrast, potassium contracture was not inhibited by lanthanum. When the muscle preparation was treated with neuraminidase, the twitch inhibition caused by lanthanum was strongly depressed.
Electron microscopic observation revealed that the precipitates of lanthanum were localized on the external lamina of myocytes as well as in the extracellular spaces but could never be found within the cytoplasm. No such precipitates could be detected in the neuraminidase-treated muscle.
From these results it is suggested that lanthanum takes the place of calcium at the membrane surface: it modifies permeabilities to sodium, potassium and calcium ions and the excitation-contraction coupling of the ventricular muscle by replacing calcium bound to the membrane surface.抄録全体を表示PDF形式でダウンロード (8914K) -
大藪 由夫, 吉田 明夫, 林 文明, 本田 良行1982 年 32 巻 4 号 p. 627-636
発行日: 1982年
公開日: 2011/06/07
ジャーナル フリーWhether or not stimulation of the peripheral chemoreceptors by hypercapnic-hypoxic exposure results in a long-lasting increase in ventilatory activities was studied using the steady state CO2 response test on 12 human subjects. The degree of hypercapnic hypoxia was end-tidal PCO2 (PETCO2) 42.±3.0 and PO2 (PET02) 39.8±4.7 mmHg, lasting for 5 min. Minute ventilation values at PETCO2 45 mmHg (V45) and PETCO2 at minute volume 15 liter·min-1 (P15) were calculated from the respective CO2 response curves. The differences in V45 and P15 between the control and the 30 min test group were found to be significant (p<0.05). These results suggested the left- and upward-shift of the CO2 response curve of the 30 min test group.
On the other hand, in 5 of the 12 subjects, three successive CO2 response tests conducted at 0, 30, and 90 min without hypercapnic-hypoxic exposure showed fairly reproducible results, and no statistically significant differences were found between any of the above trials with the parameters S, B, V45, and P15.
These results indicated that the CO2 response curve obtained by using the steady state method can be effected for at least 30 min even if the stimulation of the peripheral chemoreceptors is only for brief periods.抄録全体を表示PDF形式でダウンロード (761K) -
高田 真理1982 年 32 巻 4 号 p. 637-646
発行日: 1982年
公開日: 2011/06/07
ジャーナル フリーFour experimental setups for examining active sodium transport by frog skin were examined and compared. They were:(I) a cannula, the interior of which faced the dermis;(II) a cannula, the interior of which faced the epidermis;(III) an Ussing-type chamber without gaskets; and (IV) an Ussing-type chamber with gaskets. The experiments were carried out in SO4-Ringer's solution. In control saline, the magnitude of the short circuit current (SCC μA/cm2) was in the order: I>III>II=IV, while the magnitude of skin resistance (RM, kΩ·cm2) and potential difference were: II=IV>III>I. The responses of the skin to amiloride and cadmium varied greatly according to the various setups employed. Amiloride decreased the SCC and increased the RM. The percent differences from the control SCC and RM showed I=IV>II and IV=II>I, respectively. On the other hand, cadmium increased the SCC and decreased the RM. The orders of percent differences from the control SCC and RM were IV=II>I and II=IV>I. The effect of calcium gluconate on the active Na transport was also different depending on the various setups used; the responses to epidermal and dermal Ca-gluconate were quite opposite. The above seemingly curious findings are discussed in terms of the ENa, RNa, and RΣ obtained with Helman's Na-free saline method. From the present investigation, it is clear that careful attention should be given to the interpretation of experimental results in active transport studies when various kinds of setups are employed.抄録全体を表示PDF形式でダウンロード (1014K) -
平田 耕造1982 年 32 巻 4 号 p. 647-653
発行日: 1982年
公開日: 2011/06/07
ジャーナル フリーThe calorigenesis occurring in brown adipose tissues (BAT) in response to infused norepinephrine [NE: 4μg/(kg·min)] was estimated from the arteriovenous O2 difference across the interscapular brown adipose tissue and the rate of blood flow to BAT in physically trained (TR) and control (CT) rats. TR rats were trained by 2-hr daily swimming in agitated water at 36°C for 18 weeks. The colonic temperature was maintained at approximately 37.5°C throughout the training period. With NE infusion, the O2 content of arterial blood was unchanged, but that from Sulzer's vein significantly decreased from 12.5 to 2.5 vol % in TR and from 15.7 to 4.3 vol % in CT rats. The increase in O2 consumption in BAT with NE was estimated as 1.60 ml/min in TR and 0.83 ml/min in CT rats. The increase in the whole body O2 consumption with NE was 3.19 ml/min in TR and 2.29 ml/min in CT rats. The contribution of calorigenesis in BAT to the whole body calorigenic response to NE was estimated at 50 % in TR and 36 % in CT rats. These results directly demonstrated that physical training per se causes an enhancement of the calorigenic response of brown adipose tissues to norepinephrine in rats.抄録全体を表示PDF形式でダウンロード (726K) -
大藪 由夫, 吉田 明夫, 林 文明, 佐藤 宣践, 本田 良行1982 年 32 巻 4 号 p. 655-665
発行日: 1982年
公開日: 2011/06/07
ジャーナル フリーFifty-two active Judo athletes were examined using an isocapnic progressive hypoxia test. The results were analyzed by the hyperbola ventilation equation V=Vo H- A/(PETO2-C), where Vis observed ventilation, Vo the horizontal asymptote in ventilation for infinite end-tidal Po 2 (PETO2), A the slope constant indicating magnitude of hypoxic sensitivity, and C the vertical asymptote in PETO2 for infinite ventilation.
Hypoxic sensitivity, A, was positively correlated with body weight (BW). Such correlation in the light and middleweight groups (BW<95 kg) and the heavyweight group (BW>95 kg) with Röhrer's index being less than 200 became insignificant when the A value was recalculated after normalization of ventilation for 70 kg body mass. However, the heavyweight group with a Röhrer index of higher than 200 still exhibited a significantly higher A value than the light and middleweight groups after normalization of ventilation. These results indicated that body weight plus obesity were determining factors in the increase of hypoxic sensitivity in our subjects.抄録全体を表示PDF形式でダウンロード (1149K) -
伊藤 眞次, 勝浦 五郎1982 年 32 巻 4 号 p. 667-675
発行日: 1982年
公開日: 2011/06/07
ジャーナル フリーEffects of intracerebroventricular administration of β-endorphin, thyrotropin-releasing hormone (TRH), cholecystokinin octapeptide (CCK-8), non-sulfated CCK-8 (CCK-8-NS) and caerulein on body shaking behavior were observed in rats. CCK-8 and its related peptides produced only a small increase in the number of body shakes, while TRH had the striking effect of stimulating body shakes, this increase being markedly suppressed by simultaneous administration of β-endorphin. Moreover, the suppressive effect of β-endorphin on TRH-induced body shakes was antagonized by simultaneous administration of caerulein and CCK-8. The body shakes induced by ice-water immersion were also reduced by β-endorphin, this β-endorphin effect being partly antagonized by caerulein and CCK-8.抄録全体を表示PDF形式でダウンロード (937K) -
伊藤 眞次, 広田 良二1982 年 32 巻 4 号 p. 677-681
発行日: 1982年
公開日: 2011/06/07
ジャーナル フリーIntracerebroventricular injection of vasoactive intestinal polypeptide (VIP) into rat caused a temporary elevation of body temperature followed by a decrease to below the control level. Hypothermia induced by cholecystokinin octapeptide was abolished by simultaneous administration of VIP. Hypothermia following pentobarbital administration was reduced by successive injections of VIP. The results suggest that multiple interactions of neuropeptides are involved in central thermoregulation.抄録全体を表示PDF形式でダウンロード (426K) -
野村 浩道, 熊井 敏文1982 年 32 巻 4 号 p. 683-687
発行日: 1982年
公開日: 2011/06/07
ジャーナル フリーFungiform papillae in the frog tongue were found to contain chemoreceptors which respond phasically to quinine hydrochloride. The reflex discharge of the hypoglossal nerve on chemical stimulation of the tongue may originate from the excitation of these chemoreceptors.抄録全体を表示PDF形式でダウンロード (793K)
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