巻号一覧
26 巻, 6 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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島村 宗夫, 木暮 いく子, 井草 幸夫1976 年 26 巻 6 号 p. 577-589
発行日: 1976年
公開日: 2011/06/07
ジャーナル フリーTwenty-six chloralosed cats were employed in order to determine spinal ascending pathways of the spino-bulbo-spinal (SBS) reflex evoked by stimulation of the sural nerve.
1. Partial spinal transection of the dorsal part of the lateral funiculus abolished the SBS reflex ipsilateral to sural nerve stimulation.
2. By recording spinal cord potentials in response to sural nerve stimulation two pathways were established in the dorsolateral funiculus as the spinal ascending tracts of the SBS reflex; one is the direct pathway to the bulbar reticular-formation (direct spino-reticular tract) and the other one (indirect spino-reticular tract) is the relayed by the lateral cervical nucleus. Direct stimulation of the dorsolateral funiculus at the lumbar level elicited the SBS reflex.
3. Short-latency unit discharges were recorded from axons of the direct spino-reticular tract by sural nerve stimulation. These axons were discharged antidromically by stimulation of the bulbar reticular formation.
4. Intracellular recordings from the neurons of the lateral cervical nucleus revealed that spike potentials, riding on EPSPs, were induced by sural nerve stimulation and antidromic firings were obtained by stimulation of the bulbar reticular formation.
5. Neurons originating the spino-reticular tract, direct and indirect, were located in the Rexed V-VII laminae in the lower lumbar segments. They were fired monosynaptically by sural nerve stimulation and antidromically by stimulating the dorsolateral funiculus of the lumbar segments.Among them, some were activated antidromically by stimulating the bulbar reticular formation.抄録全体を表示PDF形式でダウンロード (3078K) -
豊田 順一, 近藤 博明1976 年 26 巻 6 号 p. 591-601
発行日: 1976年
公開日: 2011/06/07
ジャーナル フリーFrequency characteristics of photopic and scotopic L-type S-potentials were studied in the carp retina, using either an impulse or a sinusoidal light input superimposed on a steady background light of various intensities. The photopic type responses were faster than the scotopic responses if their frequency characteristics were compared without background illumination. However, the difference was not absolute. Both types of responses became faster in the presence of background illumination. The stronger the background, the faster was the response. At relatively high background intensities, the response to a flash became diphasic due to the rebound effect which corresponds to a low frequency attenuation in the gain characteristics. The main difference between the two types of responses was found in the phase relation; the scotopic units showed more phase lag indicating an extra delay even under a condition in which the time course of their response was faster than that of the photopic units.抄録全体を表示PDF形式でダウンロード (1186K) -
宮本 嘉巳, 三上 智久1976 年 26 巻 6 号 p. 603-618
発行日: 1976年
公開日: 2011/06/07
ジャーナル フリーMechanical characteristics of liquid breathing were studied in isolated lungs of guinea pigs filled with fluorocarbons FC-75 and 77. It was found that compliance increased to 2-2.5 times, resistance in creased to 20 times, and maximum expiratory flow decreased to 1/20-1/25 times the corresponding values observed in air-filled lungs. The maximum volume of ventilation during liquid breathing was then predicted to be 50ml/min from parameters mentioned above, and about 80% of such ventilation was actually observed in anesthetized animals. Measurements on O2-uptake and CO2-output as well as gas analysis of arterial blood showed that the ventilation volume was insufficient to maintain the normal gas exchange in the animal unless body temperature was lowered.An increase in physiological dead space observed during liquid breathing suggested that slow diffusion rate of gases through the liquid was responsible for the deficiency of the gas exchange.抄録全体を表示PDF形式でダウンロード (1720K) -
野間 昭典1976 年 26 巻 6 号 p. 619-630
発行日: 1976年
公開日: 2011/06/07
ジャーナル フリーTo determine the effect of high extracellular potassium concentration ([K]o) on the membrane current of the sinoatrial node cell, voltage clamp experiments were conducted using the double microelectrode technique. When depolarizing clamp pulses were applied, a transient inward current was followed by an outward current and an outward current tail flowed after the pulse. The amplitude of both the transient inward current and the outward current tail were markedly reduced with increasing [K]o, but the magnitude of the outward current during depolarization scarcely changed. The inward current during hyperpolarizing clamp pulses increased in magnitude at higher [K]o and the reversal potential for the inward current change decreased with increasing [K]o.
From these results it was concluded that the suppression of the sinoatrial node automaticity at higher [K]o was due to the decrease in magnitude of both the transient inward current and the outward current tail. As the cause of the depression of the transient inward current, its inactivation through depolarization, increased outward leak current and some direct inhibitory effect of K were proposed. The reduction of the outward current tail was attributed to the decrease in the driving force of the K current.抄録全体を表示PDF形式でダウンロード (1303K) -
藤本 守, 窪田 隆裕1976 年 26 巻 6 号 p. 631-650
発行日: 1976年
公開日: 2011/06/07
ジャーナル フリーDouble-barreled potassium or chloride ion-selective microelectrodes were constructed using a liquid ion exchanger. Technical details of the fabrication of double-barreled microelectrodes, having a PD sensor as one barrel and an ionic sensor as the other, are described.
The sensitivity of K+ or Cl- ion-selective microelectrodes exhibited an approximately Nernstian response over a temperature range of 7°C-37°C, and the electromotive force (EMF) was stable within ±1 mV for a few hours. The rise time was less than 1 sec. The effect of pH on the electrode response was negligible over a physiological range of pH 5.6 to 7.8. The selectivity constants of the K+microelectrode to other cations were 0.011 for Na+, 0.200 for NH+4, and less than 0.002 and 0.001 for Ca++ and Mg++, respectively, while that of the Cl- microelectrode was 0.067 for HCO-3. Glucose or urea has no effect on the EMF. Protein has a significant effect on ion exchanger membrane only when the concentration of the tested ion is low and protein is high.
On the basis of this background the determination of K+ and Cl- activity was carried out both in vivo and in vitro on several biological samples, such as serum, tissue and cellular fluids, and other protein-containing fluids. The values obtained with the microelectrode were conslstent with those obtained with the other conventional methods or with the current theory on electrolyte solutions.
These results were taken to assure the practical application of these electrodes to biological studies in many fields.抄録全体を表示PDF形式でダウンロード (1997K) -
久場 健司, 纐纈 教三1976 年 26 巻 6 号 p. 651-669
発行日: 1976年
公開日: 2011/06/07
ジャーナル フリーThe ionic mechanism of the slow excitatory postsynaptic potential (slow EPSP), i. e. the muscarinic action of acetylcholine (ACh), was studied either by stimulating preganglionic nerves or by applying ACh in curarized sympathetic ganglion cells of bullfrogs. There are three different types of cells characterized by the effects of membrane hyperpolarization on the amplitude of slow EPSP. One group of cells showed an increase in amplitude (type 1 cell) and, in two other groups of cells, it remained unchanged (type 2 cell) or decreased (type 3 cell), when the membrane was hyperpolarized. Under the muscarinic effects of ACh, the slope membrane conductance was increased (type 1 cell), unchanged (type 2 cell) or decreased (type 3 cell) at 10-20 mV hyperpolarized levels, while it was unchanged (type 1 cell) or decreased (types 2 and 3 cells) at resting and depolarized levels. In all cells, the slow ACh potential, corresponding to the slow EPSP, was almost completely suppressed in a high K+, Ca2+-free, Na+-free solution. These results suggest that the slow EPSP is generated by increases in Na+ and Ca2+ conductance and also by a simultaneous decrease in the K+ conductance.抄録全体を表示PDF形式でダウンロード (2041K) -
松本 春子, 藪 英世, 宮崎 英策1976 年 26 巻 6 号 p. 671-680
発行日: 1976年
公開日: 2011/06/07
ジャーナル フリーBy means of both centrifugation and filtration techniques, the Ca binding activity of intestinal myosin B was studied. The binding capacity of myosin B was Ca dependent and was approximately linear when the concentration of Ca in the medium ranged from 10-4 to 10-7 M. The Ca sensitivity of ATPase activity in the same range of Ca concentration exhibited a sigmoid curve. The Scatchard plot of Ca binding showed that intestinal myosin B had at least two types of binding sites. One of these was defined as a high affinity site with an apparent affinity constant of 2.5×106M-1. The other was supposed to be a low affinity site of Ca binding. Mild trypsin treatment reduced the Ca binding capacity of intestinal myosin B by 1.45-2.44nmol/mg protein. These values are approximately the concentration of the high affinity Ca binding sites in the intestinal myosin B. A major concern regarding the effect of trypsin is that the reduction of Ca binding surely accompanied the elimination of Ca sensitivity of myosin B ATPase activity.
From these results, it seems likely that the high affinity sites of Ca binding identified in this study are based on the troponin-like component included in intestinal myosin B.抄録全体を表示PDF形式でダウンロード (1048K) -
北村 憲司, 鈴木 光, 栗山 煕1976 年 26 巻 6 号 p. 681-692
発行日: 1976年
公開日: 2011/06/07
ジャーナル フリーThe effects of prostaglandins on electrical and mechanical properties of the rabbit pulmonary artery and portal vein were investigated and compared with those recorded from the guinea pig. In the pulmonary artery, PGE1 and PGE2 (10-9-10-6g/ml) had no effect on mechanical properties, but PGF2α (10-8g/ml) produced tonic contraction, while in the portal vein, PGE1 and PGE2 caused relaxation of the tissues. When the tissue of the pulmonary artery contracted from pretreatment with noradrenaline (10-7g/ml), PGE1 and PGE2 experienced partial, incomplete, relaxation, while PGF2α enhanced the mechanical response produced by noradrenaline.
At concentrations of 10-7g/ml, PGE1 and PGE2 hyperpolarized the membranes in both smooth muscle tissues while PGF2α depolarized them. These agents decreased membrane resistance at all membrane potential levels to values below those measured in Krebs solution. PGF2α (10-6 g/ml) applied simultaneously with procaine (1.4-2.7×10-3g/ml) markedly enhanced the mechanical responses of both tissues beyond the effects evoked by PGF2α alone. However, noradrenaline (10-8 and 10-7g/ml) applied simultaneously with procaine (1.4×10-3g/ml) markedly suppressed the mechanical responses evoked by noradrenaline alone.
It is concluded that PGE1 and PGE2 brought about relaxation of both tissues (vasodilation). while PGF2α brought about contraction (vasoconstriction). The excitatory action of PGF2α (10-5g/ml) and noradrenaline (10-7g/ml) on the electrical and mechanical responses appear as the same phenomena, i. e., depolarized membrane, decreased membrane resistance and contraction, although the mechanisms producing the above phenomena differ.抄録全体を表示PDF形式でダウンロード (1343K) -
EFFECTS OF INTRACELLULAR pH ON PLATEAU FORMATION FOLLOWING THE ACTION POTENTIAL OF SQUID GIANT AXONS寺川 進, 渡辺 昭1976 年 26 巻 6 号 p. 693-701
発行日: 1976年
公開日: 2011/06/07
ジャーナル フリーWhen squid giant axons were intracellularly perfused for about 10min with 100mm K+ solutions containing Pronase or Protease Type VII at a concentration of 0.1-0.5mg/ml, the action potential developed a long-lasting plateau. The plateau persisted after switching to an enzymefree solution at standard pH (7.3±0.1) as the intracellular perfusate. The plateau was promptly and completely suppressed when the intracellular pH was lowered below 6.5. Upon increase of pH again to the standard level, the plateau promptly reappeared. With alkaline intracellular pH plateau formation was enhanced. Lowering the pH of the extracellular medium to 5 did not influence the plateau. The duration of the action potential under bi-ionic conditions (inside Cs+, outside Ca++) decreased with low intracellular pH and increased with high intracellular pH. The plateau duration of the action potential from axons intracellularly perfused with solutions containing 10mM tetraethylammonium also decreased with low intracellular pH and increased with high intracellular pH. The underlying mechanisms for the pH effects remain to be explored.抄録全体を表示PDF形式でダウンロード (919K) -
久場 健司, 纐纈 教三1976 年 26 巻 6 号 p. 703-716
発行日: 1976年
公開日: 2011/06/07
ジャーナル フリーThe direct effects of acetylcholine (ACh) on Na+-or Ca2+-dependent action potentials of curarized sympathetic ganglion cells in bullfrogs were investigated under a condition where membrane depolarization caused by the muscarinic action of ACh was nullified by means of a hyperpolarizing current. ACh decreased the after-hyperpolarization of Na+-action potentials in Ringer's solution, and increased the after-depolarization of Ca2+-action potentials in the isotonic Ca2+solution. In both solutions, the maximum rates of rise of the spikes were decreased and the slope membrane resistance at the original resting level was increased. The effects of ACh were abolished by atropine. On the other hand, ACh showed no significant effects on action potentials of bullfrog spinal ganglion cells which possessed no synapses. These results suggest that the ion conductance channels for generation of action potentials of sympathetic ganglion cells are under the direct control of transmitters, such as ACh.抄録全体を表示PDF形式でダウンロード (1665K) -
砂野 哲1976 年 26 巻 6 号 p. 717-727
発行日: 1976年
公開日: 2011/06/07
ジャーナル フリーSome charasteristic properties of guinea pig ureter in high-K induced contracture were studied. The contracture was composed of three contraction components, quick phasic, slow transient, and substained states. The height of the second component decreased with time when the preparation was immersed in high-K solution. This was observed during a brief washing treatment with normal Tyrode solution applie at various time after immersion in high-K solution. When the brief washing treatment was applied after 30 min, a contracture composed of the first and the third components was observed. Similar results were obtained in Ca-induced contracture of K-depolarized preparations.
Fluctuations of tension were observed in the course of the contracture. The fluctuations could be evoked by various types treatments and were observed to have some relationship to extracellular Ca. It was indicated that extracellular Ca has an important role in the initiation of each component of the contracture and that the role of Ca is controlled by the cell membrane.抄録全体を表示PDF形式でダウンロード (1075K)
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