巻号一覧
34 巻, 2 号
選択された号の論文の16件中1～16を表示しています
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中馬 一郎1984 年 34 巻 2 号 p. 205-216
発行日: 1984年
公開日: 2006/07/28
ジャーナル フリーProtons and carbon dioxide are physiological regulators for the oxygen affinity of hemoglobin. The heterotropic allosteric interaction between the non-heme ligands and oxygen, collectively called the Bohr effect, facilitates not only the transport of oxygen but also the exchange of carbon dioxide. Several types of interactions can be thermodynamically formulated. The Bohr and Haldane coefficients and the classical Bohr and Haldane coefficients are thus explicitly defined, which will save confusion about the use of the term "Bohr effect" seen in the literature. Molecular mechanism and the physiological significance of the classical Bohr and Haldane effects are outlined. The latter effect seems to play a far greater physiological role than the reciprocal influence of carbon dioxide on oxygen transport-the classical Bohr effect.抄録全体を表示PDF形式でダウンロード (917K) -
寺沢 崇, 伊藤 俊晴, 松田 稔, 吾妻 達郎, 葛西 四朗1984 年 34 巻 2 号 p. 217-224
発行日: 1984年
公開日: 2006/07/28
ジャーナル フリーUsing methylcellulose clonal cell cultures, we examined human erythroid burst-promoting activity (BPA) in sera obtained from umbilical cord blood. BPA was measured on the basis of the number of erythroid bursts (BFU-E) and hemoglobin synthesis when peripheral blood mononuclear cells were cultured with cord blood serum in the presence of 1.0U/ml erythropoietin (Epo) at low fetal calf serum concentration (10%). Controls were cultured with adult serum. The number of BFU-E and hemoglobin synthesis increased in culture to which cord blood serumhad been added, and the enhancing effects of cord blood serum on erythroid burst formation were more pronounced than in control cultures with 2.0U/ml Epo. No erythroid bursts, however, grew in the cultures with cord blood serum in the absence of Epo. Increased sensitivity of erythroid burst formation to low concentrations of Epo was observed in cultures containing cord blood serum. Dose-relationships between the concentrations of cord blood serum and the number of BFU-E and hemoglobin synthesis were clearly observed. We therefore concluded that the stimulatory effects of cord blood serum on erythroid burst formation may be due to BPA, one of the factors required for the proliferation of erythroid precursors at an early stage.抄録全体を表示PDF形式でダウンロード (851K) -
小豆島 正典1984 年 34 巻 2 号 p. 225-243
発行日: 1984年
公開日: 2006/07/28
ジャーナル フリー1) The abdominal ganglion of Aplysia includes neurons with a characteristic dopamine (DA) receptor, the activation of which induces a marked hyperpolarization with a specific increase in the permeability of the membrane to K+. The DA receptor of this type is called the "HK-type." 2) A 2-min exposure to 1μM serotonin (5-HT) had little effect on the resting membranes with the receptor of HK-type, but significantly depressed the responses to 10μM DA. The depressing effect of 5-HT on this type of response was completely reversible after a 15-min washing with normal artificial Aplysia blood. 3) Lineweaver-Burke type plotting of the DA-induced responses showed a systematic shift of the straight lines when the concentration of 5-HT was increased; the slope of the line became steeper but the intercept on the ordinate remained unchanged. 4) The dose-inhibition curves, in which relative responses to a given [DA] were plotted against log [5-HT], showed a parallel shift toward the right when the concentration of DA increased. 5) These findings suggest that 5-HT competes with DA for common binding sites at the DA receptor of HK-type, and that the blockade is not due to the interaction of 5-HT with K+-channels in the receptor membrane. 6) The effect of other indole derivatives suggests that the DA receptor of HK-type includes anionic and cationic sites to which the NH2 group and 5-HO group of 5-HT could specifically bind, thus exhibiting competitive blockade.抄録全体を表示PDF形式でダウンロード (1289K) -
野間 昭典, 中山 敏夫, 倉智 嘉久, 入沢 宏1984 年 34 巻 2 号 p. 245-254
発行日: 1984年
公開日: 2006/07/28
ジャーナル フリーCurrents through the inward rectifier K channel (iK•rec) and the ACh-operated K channel (iK•ACh) were recorded in isolated heart cells of rabbit using the patch clamp technique with electrodes having 0.5-1μm tip inner diameter. The maximum number of overlaps of open iK•rec channels per patch was measured over 347 experiments. An average of 2.3 was found in ventricular cells and 0.03-0.06 in sinoatrial (S-A) and atrioventricular (A-V) node cells. The estimated total number of the iK•rec channels for each ventricular cell was great enough to supply the resting K conductance of the cell. The ik•ACh channel was present in S-A and A-V node cells, but was never observed in the ventricular cells. The resting conductance of the nodal cells measured with whole cell clamp recordings was about 16 times smaller than that of the ventricular cells, and was hardly decreased at all by the removal of K+ from the bath solution. Thus, the lower membrane potential of the nodal cells compared with that of the ventricular cells was attributed to the smaller K conductance of the resting membrane, which is due to the very low density of the iK•rec channel. On the other hand, the iK•ACh channel, when activated by neural regulation, may play a major role in generating the resting K conductance of the nodal cells.抄録全体を表示PDF形式でダウンロード (715K) -
小川 尚, 山下 由朗, 野村 朝清, 谷口 紘八1984 年 34 巻 2 号 p. 255-267
発行日: 1984年
公開日: 2006/07/28
ジャーナル フリーDischarge patterns of slowly adapting (SA) mechanoreceptor afferent units innervating the non-warty skin of frogs, were analyzed statistically. Because SA units in the frog did not always produce sustained discharges for a long period, analysis was carried out on ensembles of interspike intervals (ISIs) obtained in two ways: (1) a series of successive ISIs obtained in the quasi-stationary state of maintained discharges and (2) an ensemble of ISIs (X(1), X(2), … X(50)), obtained on repeated trials of stimulation at about 1, 000msec following the onset of stimulation. In some units these two types of ensembles of ISIs were collected. Statistical analysis of a series of successive ISIs in the quasi-stationary state disclosed two kinds of discharge patterns, irregular and regular, corresponding to those of the SA cutaneous units of mammals and reptiles. We named these two types of units Frog type I and Frog type II (Ft I and Ft II) units, respectively. In addition, the quantitative studyof an ensemble of ISIs in the non-stationary state revealed that Ft II units discharged regularly in response to an optimum range of indentation but irregularly to indentation outside this range, although Ft I units produced irregular discharges irrespective of the magnitude of indentation applied.抄録全体を表示PDF形式でダウンロード (944K) -
榊原 吉一1984 年 34 巻 2 号 p. 269-282
発行日: 1984年
公開日: 2006/07/28
ジャーナル フリーThe electrical activity of the cranial nerves innervating the muscles which contract and dilate the buccal cavity (defined BCcont and BCdil, respectively) was explored in the bullfrog, Rana catesbeiana. The sternohyoid branch of the hypoglossal nerve innervating BCdil showed electrical activity in two consecutive phases: buccal inhalation and lung expiration as well as in the last phase of the pulmonary ventilatory cycle. The last phasic activity was apparently identical to the first one of the succeeding cycle when the cycles were repeated consecutively. The nerves innervating BCcont, consisting of the Vth, VIIth, IXth, Xth, and XIIth cranial nerves, generally showed two consecutive phasic activities in the period of lung expiration and lung inspiration. Thus the present result indicated that during three consecutive phases of the pulmonary ventilatory cycle, the nerve for BCdil was active in the first two phases, and the nerves for BCcont in the last two phases. In both nerve activities the magnitude of the integrated peak activity was smaller in the preceding than in the later phase. In the buccal oscillation cycle, the nerve for BCdil was active during pressure depression while the nerves for BCcont were active during pressure elevation in the buccal cavity. The nerves for both mouth closing and that for tongue retraction had phasic activity during respiratory cycles.抄録全体を表示PDF形式でダウンロード (1036K) -
川上 恭司, 入内島 十郎1984 年 34 巻 2 号 p. 283-294
発行日: 1984年
公開日: 2006/07/28
ジャーナル フリーIn rats chronically implanted with an electromagnetic flow probe around the ascending aorta, terminal aorta, or superior mesenteric artery as well as arterial and venous indwelling catheters, changes in cardiac output, hindquarter flow, splanchnic flow, and arterial pressure on pentobarbital anesthesia were observed. On intravenous injection of pentobarbital sodium at 30mg/kg, arterial pressure dropped acutely from an average value of about 105mmHg to a minimum of about 75mmHg in about 5min and then gradually recovered to an average level of about 90mmHg in 30min. Cardiac index gradually decreased about 30% on the average in 30min. Hindquarter flow decreased about 25%. Superior mesenteric flow first increased about 40% within 5min and then returned almost to the premedication level in 30min. In adrenalectomized rats there was no decrease of hindquarter flow on pentobarbital anesthesia. The increase in superior mesenteric flow immediately after pentobarbital injection remained almost unchanged after adrenalectomy or splanchnicectomy. It is concluded that an appreciable portion of the decrease in cardiac output on pentobarbital anesthesia is induced by inhibition of tonic adrenomedullary secretion which has a dilating effect on muscle blood vessels through stimulation of β-receptors. The marked increase in splanchnic flow immediately after pentobarbital injection, which is responsible for the concomitant drop in arterial pressure, is considered to be induced by a direct inhibitory effect of the anesthetic on splanchnic blood vessels.抄録全体を表示PDF形式でダウンロード (784K) -
望月 政司, 田村 和一, 島崎 朋司, 新関 久一, 下内 章人1984 年 34 巻 2 号 p. 295-306
発行日: 1984年
公開日: 2006/07/28
ジャーナル フリーA new indirect method for measuring the arteriovenous O2 content difference (avDO2) was developed. The avDO2 was calculated by dividing the gradient of the CO2 dissociation curve by that of a gas exchange ratio against PCO2. The latter slope was obtained from O2 and CO2 concentrations in rebreathing air. The validity of the method was tested preliminarily in human subjects by comparing the cardiac output calculated from avDO2 and O2 uptake (VO2) with that measured hitherto by other authors, and then in dogs by comparing the calculated avDO2 with the measured value. In the dog experiments, the rebreathing was performed 7 times in each of 7 dogs. Immediately after the rebreathing arterial and mixed venous blood were sampled and analyzed for avDO2. For each rebreathing period the avDO2 was calculated by using the CO2 dissociation curve obtained in the individual dogs. The correlation coefficient between the measured and calculated avDO2 was 0.87, demonstrating reasonable validity of the method. The VO2 was further measured from the time interval during which a known amount of pure O2 was consumed. Then, the cardiac output was calculated by dividing the VO2 by the measured and calculated avDO2. The correlation coefficient between the respective cardiac output values was 0.88, indicating the reliability of using the calculated avDO2.抄録全体を表示PDF形式でダウンロード (802K) -
宮地 栄一, 高橋 恭一, 村上 元彦1984 年 34 巻 2 号 p. 307-318
発行日: 1984年
公開日: 2006/07/28
ジャーナル フリーIn the rod of the isolated frog retina perfused with normal Ringer solution, a transretinal current pulse flowing from the receptor side to the vitreous side evoked a response consisting of a transient depolarization and a subsequent damped oscillation. The transient depolarization was not an all-or-none response, but was a graded one which depended on the intensity and duration of the electrical stimulation. The amplitude of the initial depolarization varied with Ca2+ concentrations of the perfusate, being enhanced in the high Ca2+ and reduced in the low Ca2+ medium. Furthermore, it was enhanced by perfusion with a Ba2+-containing solution, and suppressed by exposure to Co2+. These observations suggest that the initial depolarization can be attributed to an increase of Ca2+ conductance. The late hyperpolarization which followed the initial depolarization was suppressed by membrane depolarization and was enhanced by membrane hyperpolarization. In addition, the evoked responses were not affected by application of either L-aspartate or L-glutamate, both of which blocked the synaptic transmission from the photoreceptors to the second order neurons. Thus it is unlikely that the late hyperpolarization is an IPSP-like response evoked by the negative feedback input from horizontal cells. Rather the rod membrane itself seems to have an oscillatory property.抄録全体を表示PDF形式でダウンロード (884K) -
川崎 了二1984 年 34 巻 2 号 p. 319-335
発行日: 1984年
公開日: 2006/07/28
ジャーナル フリーTo examine the breathing rhythm-generating mechanism, effects of brain sectioning, immobilization, and electric stimulation on medullary respiratory activities were investigated in adult lampreys. 1) The rostral part of the medulla (rostrally to the level of the caudal border of "internal acoustic pore") is not indispensable for breathing rhythm-generation. The rostral part itself, however, was also capable of driving periodic movement of only the first branchial baskets. 2) After immobilization, respiratory discharges continued without changing their pattern, indicating that respiratory afferents do not modulate the centrally generating rhythm. 3) Respiratory discharges recorded simultaneously from the right and left side of the medulla showed bilateral synchronization. After sectioning the midline of the brain, each of the symmetric halves of the medulla behaved as an independent respiratory pacemaker. 4) Respiratory discharges were driven in one-to-one fashion by electric stimulus applied to the medulla, almost independently of timing of stimulus delivery. Stimulus pulses applied during respiratory discharges did not inhibit these discharges: electrically driven discharge summated or fused with the spontaneous firing. 5) Slow and smoothly depolarizing potential preceding respiratory spike discharges was recorded intracellularly from the half of the brain-stem divided by midline sagittal sectioning in the immobilized animal. 6) These results were discussed in light of the hypothesis that respiratory burst generator mechanism in the lamprey may be similar to cardiac pacemakers.抄録全体を表示PDF形式でダウンロード (1257K) -
八谷 アツ子, 井本 浩, 後藤 昌義1984 年 34 巻 2 号 p. 337-349
発行日: 1984年
公開日: 2006/07/28
ジャーナル フリーThe effects of caffeine on ionic currents in isolated, single cells from rat ventricles were compared with the effects of adrenaline. In current-clamp experiments, caffeine (1.0 to 10.0mM) increased both the height of the plateau and the duration of the action potential. Both caffeine and adrenaline increased the amplitude and duration of the slow responses. Voltage-clamp experiments reveal that the repolarization phase of the action potential in isolated cells is determined mainly by the slow inward current (Is), which has voltage-dependent kinetics similar to the Is in intact cardiac tissue. No evidence of a time-dependent outward current (Ix), or a hyperpolarization-induced inward current (Ih) or (If) was found, although a time-independent background current (Ik1) was observed. Caffeine increased the amplitude of Is, but did not change its time course, its voltage dependency (of steady-state inactivation and activation), or its apparent reversal potential. Ik1 is not affected by the caffeine. The results indicated that the effects of caffeine were nearly identical to those of adrenaline. The effects of caffeine on the electrical properties of single cells from rat ventricles derive chiefly from its action on Is channels.抄録全体を表示PDF形式でダウンロード (1075K) -
小山 省三, 寺田 信幸, 塩島 由美子, 竹内 亨1984 年 34 巻 2 号 p. 351-355
発行日: 1984年
公開日: 2006/07/28
ジャーナル フリーIntravenous administration of leucine-enkephalin (30μg/kg) caused significant decreases in mean blood pressure, cardiac output, and left ventricular dP/dt in intact dogs. However, cardiovascular effects of leucine-enkephalin (30-120μg/kg) did not occur in the heart-lung preparation uninfluenced by extracardiopulmonary factors. These results provide no evidence of a direct cardiac action of leucine-enkephalin.抄録全体を表示PDF形式でダウンロード (393K) -
H. Westcott VAYO, 柴田 正憲1984 年 34 巻 2 号 p. 357-360
発行日: 1984年
公開日: 2006/07/28
ジャーナル フリーThe length of arc or circumference for the cross-section of the red blood cell has been determined for the normal range of dimensional values for mammalian red cells. Graphs for arc length vs. diameter and vs. cross-sectional area, for fixed thickness, are included. The graphs give an indication of the rates of change of the geometrical parameters contained therein. A special case of Fick's Law, based on the model geometry utilizing the Oval of Cassini, is presented for the mammalian red cell. The ratios of surface area to volume necessary for a complete Fick's Law formulation, are given for the normal range of dimensional values for the mammalian red cell.抄録全体を表示PDF形式でダウンロード (235K) -
越智 和典, 松村 幹郎1984 年 34 巻 2 号 p. 361-364
発行日: 1984年
公開日: 2006/07/28
ジャーナル フリーArsenazo III was injected into a Xenopus skeletal muscle fiber to measure the changes in myoplasmic free Ca2+ concentration following an action potential. The arsenazo III signal started to rise after a latent period of 2.4msec, attained its peak at another 5.0msec and then decayed exponentially with a half time of 15.6msec, at 22-24°C. Nitrate ions prolonged the falling phase with a slight increase in the peak amplitude. It is suggested that nitrate produces continuous Ca release as well as augmentation of the initial burst of Ca release in highly stretched muscle fibers.抄録全体を表示PDF形式でダウンロード (336K) -
高橋 徳之1984 年 34 巻 2 号 p. 365-368
発行日: 1984年
公開日: 2006/07/28
ジャーナル フリーWhen 3, 5-dmethyl-3′-isopropyl-L-thyronine (DIMIT) (10ng/(g•day)) was administered to pregnant rats, their infants showed signs of hyperthyroidism with suppressed body weight, tachycardia, and tremor at the day of birth. The brain weight did not change but the wet weight of the cerebral cortex was increased in the infants. Tubulin content (per wet weight and per whole tissue) was increased in the cerebral cortex and cerebellum but remained unchanged in the hypothalamus in the DIMIT-treated group. DIMIT-induced hyperthyroidism t was shown to affect the development of the fetal brain.抄録全体を表示PDF形式でダウンロード (287K) -
清末 達人, 青峰 正裕, 有田 真1984 年 34 巻 2 号 p. 369-373
発行日: 1984年
公開日: 2006/07/28
ジャーナル フリーEffect of lysophosphatidylcholine (LPC) on the inward rectifier K channel of the isolated guinea pig ventricular cell was studied using patch clamp technique.In that LPC (100μM) decreased the magnitude of the single channel conductance from 48±5pS (mean and S.D., n=5) to 12±9pS (n=8), this event may be the prime factor related to the alleged LPC-induced depolarization of cardiac tissues.抄録全体を表示PDF形式でダウンロード (370K)
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