巻号一覧
29 巻, 3 号
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菅 弘之1979 年 29 巻 3 号 p. 227-237
発行日: 1979年
公開日: 2011/06/07
ジャーナル フリーA method is proposed for direct assessment of the total internal mechanical work of the cardiac ventricle from a pressure-volume diagram. First, a quick release pressure-volume curve of the lumped series elasticity of the ventricle is recorded. Next, this curve is transcribed on a pressure-volume loop diagram of a contraction of interst in such a way that the quick release curve passes through the endsystolic pressure-volume data point of the loop. Finally, planimetry of the triangular area bounded by the quick release curve, the isovolumic relaxation segment of the loop and the diastolic pressure-volume curve gives total ventricular mechanical internal work performed on the lumped series elasticity of the ventricle during systole. This method is much simpler and more direct than the conventional analytical method which requires a relatively simple geometric model of the ventricle, a formula for series elasticity with appropriate stiffness constants and a series of mathematical calculations based on many unverified assumptions on the shape, structure and mechanical properties of the ventricle.抄録全体を表示PDF形式でダウンロード (1126K) -
森田 喜一郎, 纐纈 教三1979 年 29 巻 3 号 p. 239-250
発行日: 1979年
公開日: 2011/06/07
ジャーナル フリーThe effect of adrenaline (Ad) on the electrogenic Na+ pump of bullfrog visceral nerve fibers was studied, by testing the effect of this drug on the K-activated hyperpolarization (KAH) of these nerve fibers. KAHs were recorded by adding K (0.2-5 mM) to an extracellular K-free solution with which preparations were previously perfused and the actual KAH amplitude (net KAH) was estimated by taking into account the amplitude of membrane depolarization induced by K in the presence of ouabain (0.001 mM). The dose-response relation between K concentrations and net KAHs follows Michaelis-Menten kinetics; the log dose-response relation showed a sigmoid curve and the Lineweaver-Burk Plot of dose-response relation showed a straight line when nH=1.3. The net KAH was augmented by Ad (0.03-1 mM); facilitative effects of three kinds of catecholamine on the net KAH were Ad>noradrenaline>> isopreterenol. The log dose-response curve was shifted to the left in parallel in the presence of Ad; the Lineweaver-Burk plot showed a straight line when nH=1.3 and this line met the control line at the ordinate point where K concentration is infinitive, while the apparent dissociation constant (Km) decreased to 0.82 from 1.3 mM (control) in the presence of 0.3 mM Ad. Net KAH was augmented by the removal of extracellular Cl or by the action of TEA; the membrane resistance was expected to increase under these experimental conditions. The dose-response relation obtained under these conditions showed an increase of maximum response without changes in Km value. It was concluded on the basis of the present results that the increase in net KAH by Ad was due to an increase in the electrogenic Na+ pump current. The mechanism underlying such an Ad action was discussed, and it was suggested that the rate of the electrogenic Na+ pump was increased by the action of Ad.抄録全体を表示PDF形式でダウンロード (1198K) -
林 秀生, 有田 彰1979 年 29 巻 3 号 p. 251-265
発行日: 1979年
公開日: 2011/06/07
ジャーナル フリーElectrical impedance of a bullfrog ventricle was recorded epicardially by the V-I method and the bridge method together with an electrocardiogram (ECG) and a contraction curve, in terms of shortening. Impedance change during one cardiac cycle of a contracting ventricle corresponded completely to the contraction curve in its time course: impedance decreased during systole and attained minimum at the peak of contraction, and the durations of both curves were almost identical. The ratio of impedance just before T-wave to that just after R-wave (|ZT|/|ZR|) of an in situ heart was increased when the ventricle contracted isovolumetrically by means of mineral oil: the ratio was far less than 1.0 in control ventricle, while it was more than 1.0 in oilfilled one (2/3 cases). Upon isometric condition or treatment of cadmium the motion restricted ventricle caused an increase in the impedance ratio (|ZT|/|ZR|) to higher than 1.0, as in the case of oil-filled ventricle. The epicardial recording of ventricular impedance seems to consist of two components: contraction (shortening)-dependent impedance change and contraction (shortening)-independent impedance change, which reflects the membrane activity. Vigorous contraction will probably mask the latter and reveal only the former.抄録全体を表示PDF形式でダウンロード (1924K) -
小山 富康, 堀本 和志, 菊池 佑二, 垣内 義弘, 新居 孝1979 年 29 巻 3 号 p. 267-274
発行日: 1979年
公開日: 2011/06/07
ジャーナル フリーThe left anterior descending branch of the coronary artery (LAD) of anesthetized, open-chest dogs was perfused by intraventricular pressure (systolic perfusion) and aortic blood pressure (aortic perfusion) alternately. When the LAD perfusion was switched from aortic perfusion to the systolic one, the subendocardial PO2 decreased to 9.8 mmHg, on an average, in 1 to 2 min from the initial level of 18.9 mmHg obtained during the aortic perfusion. On total occlusion of LAD, the subendocardial PO2 fell to 4.5 mmHg, while the subepicardial PO2 showed no significant change. These results suggest that a small amount of oxygen is transported to the subendocardium during the systolic phase despite the impaired blood flow to the subendocardium and that the oxygen supply to subepicardium can be supported even though the LAD perfusion is restricted to the systolic phase.抄録全体を表示PDF形式でダウンロード (1328K) -
永井 格, 小原 一男, 太田 勲, 永井 寅男1979 年 29 巻 3 号 p. 275-281
発行日: 1979年
公開日: 2011/06/07
ジャーナル フリーEffect of transverse tubule-disruption (T-disruption) on 14C-caffeine influx was studied using small bundles, consisting of 40 to 50 fibers, of frog semitendinosus muscle. The peak tension of caffeine contracture was inhibited by about 69 % at 5 mM caffeine and by about 31 % at 7 mM caffeine by T-disruption. In addition, the amount of caffeine influx in a small bundle was inhibited by about 52 % at 5 mM caffeine and by about 28 at 7 mM caffeine by T-disruption, corresponding to the inhibition of the peak tension of caffeine contracture by Tdisruption. These findings support our previous suggestion that caffeine enters the muscle fibers through the surface membrane and transverse tubuler membrane (T-membrane), and that the T-membrane contributes to the entry of caffeine more greatly at 5 mM caffeine than at 7 mM caffeine. Moreover, at 5 mM caffeine it was noted that there is a slight difference between the extent of inhibition of the caffeine influx and that of the peak contracture tension. From these results, it could be concluded that the inhibition of peak tension of caffeine contracture by T-disruption is mainly due to the inhibition of caffeine influx which occurs through the T-membrane and is partly due to the functional disturbance of the sarcoplasmic reticulum which is probably induced by T-disruption.抄録全体を表示PDF形式でダウンロード (867K) -
福田 淳, 住友 一次, 杉谷 道男, 岩間 吉也1979 年 29 巻 3 号 p. 283-307
発行日: 1979年
公開日: 2011/06/07
ジャーナル フリーReceptive-field properties of 273 relay (principal, P-) cells of the dorsal lateral geniculate nucleus (LGd) were studied in urethaneanesthetized albino rats, in an attempt to see if there is some relation between the visual property and the conduction velocity of afferent optic nerve fibers.
According to properties of the receptive-field center, P-cells were classified into two types, common (89 %) and uncommon (11 %). The common type consists of OFF-phasic, ON-phasic, ON-tonic and ON-OFF-phasic cells, while the uncommon type includes ONinhibited, moving-sensitive, ON-OFF-inhibited, simple-cell-like and complex-cell-like cells. The mean response latency to single optic chiasm shocks increases in the order of OFF-phasic (1.94 msec), ONphasic (2.35 msec), ON-tonic (2.87 msec), ON-OFF-phasic cells (3.04 msec) and uncommon type (3.18 msec). The mean size of the receptivefield center in each of the four common types was smaller than that in the uncommon type; 6°-7°vs. 11°. From responsiveness to moving light spots with speeds faster than 25°-30°/sec, P-cells of the common type were divided into the fast- and slow-movement-sensitive cells. The ratio of occurrences of fast- to slow-movement-sensitive cells decreases in the order of the OFF-phasic (2.7), ON-phasic (2.4), ON-tonic (1.1) and ON-OFF-phasic types (0.06). The optic chiasm latencies were shorter than 2.5 msec in most of the fast-movement-sensitive cells while the reverse was true for most of the slow-movement-sensitive cells.
From these findings discussions were made to point out that the rat LGd mainly consists of Y- and W-like P-cells and that the Y/W dichotomy of P-cells approximately corresponds to the previously established fast/slow classification.抄録全体を表示PDF形式でダウンロード (5935K) -
小川 正晴, 井上 章1979 年 29 巻 3 号 p. 309-325
発行日: 1979年
公開日: 2011/06/07
ジャーナル フリーUsing suspensions of chromaffin granules isolated from bovine adreno-medullae, the effects of Mg2+·ATP on membrane potential and catecholamine release across membranes of granules were investigated. The release of catecholamine was monitored by the measurement of changes in endogenous fluorescence of the amines, while the fluorometric method with 3, 3'-dipropylthiadicarbocyanine iodide (diS-C3-(5)) was applied to the measurement of membrane potential changes. The catecholamine release brought about by Mg2+·ATP was found to obey Michaelis-Menten kinetics with Km-value for Mg2+ of about 0.15 mM and to be inhibited by dicyclohexylcarbodiimide (DCCD), an inhibitor of membrane-bound H+-ATPase. Concomitantly with such an amine release, depolarization of the granule membrane was observed to occur. The magnitude of this depolarization closely paralleled with the rate of the amine release and followed a saturation kinetics of Michaelis-Menten type with Km for Mg2+ of 0.21 mM and for ATP of 0.22 mM. Moreover, such a depolarization was competitively suppressed by DCCD. Based on these results, the role of the transmembrane potential change of granules in the catecholamine release was discussed.抄録全体を表示PDF形式でダウンロード (1880K) -
川崎 了二1979 年 29 巻 3 号 p. 327-338
発行日: 1979年
公開日: 2011/06/07
ジャーナル フリー1. The breathing rhythm-generation mechanism was studied throughout the entire body of the adult lamperey, Entosphenus japonicus, with the body fixed by a specially-designed holder.
2. After brain-stem transection, the rostral part (pontine area) and the caudal part of the medulla (Fig. 2) were found not essential for the generation of respiratory rhythm: the location of the medullary respiratory rhythm-generator was in the district limited by two crosssection lines (Fig. 2).
3. Complete division of the brain-stem into two halves by midline section revealed that both of the two symmetrical halves could function independently with their own frequencies for 2 hr or longer.
4. Respiratory burst discharges were recorded from the isolated medial part of the medulla, preceded by a so-called diastolic slow depolarization. The forms of these neural activities resemble those reported in pacemaker cells in some crustacean heart ganglion. No periodic discharges correlating exclusively to the relaxation and/or resting period of branchial muscle were observed.
5. The reciprocal inhibition model was not necessarily considered a prerequisite for medullary respiratory rhythm-generation in the lamprey.抄録全体を表示PDF形式でダウンロード (1762K) -
長 琢朗, 小笠原 利保1979 年 29 巻 3 号 p. 339-352
発行日: 1979年
公開日: 2011/06/07
ジャーナル フリーThe effects of Mg and isoprenaline on the uterine circular muscle of ovariectomized rats which were injected with estradiol for 2-6 days were investigated. The muscle strip exhibited an action potential that was composed of a spike and a plateau, and also exhibited a twitchlike contraction due to electrical stimulation. The duration of the action potential became longer when the treatment with estrogen was applied until the maximal effect was built up in 4-5 days. Both the duration of the action potential and the amplitude of contraction were reduced when isoprenaline was applied. When Mg (0.5 mm) was added to the bathing solution these β-effects were progressively potentiated and the maximal effect was obtained in about 1 hr. An increase in membrane conductance was induced by the application of isoprenaline in a control Locke solution and it was further accelerated by exposure to Mg-containing solution. The possibility that the β-action is potentiated by Mg ions which penetrated into the membrane is concluded.抄録全体を表示PDF形式でダウンロード (1452K) -
中村 彰治, 岩壷 克哉, 蔡 長添, 岩間 吉也1979 年 29 巻 3 号 p. 353-357
発行日: 1979年
公開日: 2011/06/07
ジャーナル フリーThe effects of electrical stimulation of prefrontal cortex upon neurons of substantia nigra (pars compacta) in anesthetized rats were mostly inhibition without antidromic excitation. By studying nigral neurons in which the inhibition from caudate-putamen was antagonized by iontophoretic bicuculline, it was found in only half of them that the same drug also antagonized the inhibition from prefrontal cortex.抄録全体を表示PDF形式でダウンロード (581K)
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