巻号一覧
32 巻, 1 号
選択された号の論文の15件中1～15を表示しています
- |<
- <
- 1
- >
- >|
-
森谷 恵, 宮崎 英策1982 年 32 巻 1 号 p. 1-12
発行日: 1982年
公開日: 2011/06/07
ジャーナル フリーContractile response to AC field stimulation was compared between the longitudinal and circular muscles of the guinea pig stomach under various stimulating conditions. The longitudinal muscle responded with considerable tension at any frequency between 20 and 2, 000 Hz. The circular muscle showed a peak response around 200 Hz with rapidly decreasing response to the higher frequencies of less than 800 Hz. Experiments in the presence of tetrodotoxin and atropine revealed that the circular muscle was scarcely stimulated directly (without nerve excitation) by the AC, while the longitudinal muscle was stimulated directly at frequencies higher than 400 Hz, as well as being stimulated indirectly at frequencies lower than 200 Hz. The field strength necessary to generate one-half maximum tension was higher in the circular muscle (2.8 V/cm) than in the longitudinal muscle (1.5 V/ cm at 200 Hz), although when a frequency lower or higher than 200 Hz was applied, the strength-tension curve shifted to the left or right, respectively. The contractile responses of the two muscles were graded with respect to filed duration up to maximum tension. The maximum tension and the highest rate of tension development were given at the stimulating condition of 200 Hz, 5 V/cm, for 5 sec in both types of muscles. The maximum tension generated per unit cross-sectional area of the longitudinal muscle was 19.2 g/mm2 and that of the circular muscle was 32.5 g/mm2. The maximum rates of tension development of the longitudinal and circular muscles were 9.1 and 12.1 g/(mm2·sec), respectively.抄録全体を表示PDF形式でダウンロード (1251K) -
池原 敏孝, 酒井 鉄博, 宮本 博司, 蟹池 健一1982 年 32 巻 1 号 p. 13-24
発行日: 1982年
公開日: 2011/06/07
ジャーナル フリーThe relation of membrane transport of alkali cations to their external concentrations or to their cellular contents was studied in HeLa cells. Chilling the cells at 0°C reversed cell Na+ and K+ to a mirror image of the normal pattern. Upon rewarming to 37°C the ouabainsensitive Rb+ uptake became 2-fold faster than the control. A kinetic analysis revealed that the stimulation was due to an increase in the maximal rate of Rb+ uptake, Jmax. The increase in apparent Km was relatively small. The analysis also showed that the ouabain-sensitive cation transport system seemed to have two binding sites for Rb+. The stimulation of Rb+ uptake was related to an increase in cell Nat, and an addition of ouabain abolished such a relation. Net Na+ flux which was in the direction from inside the cells to the medium at hypernormal cell Na+ was increased when cell Na+ increased. In contrast, net Nat flux which was in the opposite direction in the presence of ouabain was reduced and became almost 0 at cell Na+ of 900 nmol/mg of protein. The Na+/Rb+ coupling ratio in the ouabain-sensitive cation transport was apparently less than 1 at nearly physiological cell Nat, but it approached 1.5 when cell Na+ was sufficiently high. The sum of cell K+ plus Rb+ varied inversely with cell Nat, and this relation was unaffected upon treatment with ouabain. When Rb+ uptake declined below 80 of the control, cell K+ plus Rb+ was reduced, however, 40 % of the sum of cell cations was still preserved even after complete inhibition of the cation pumps by ouabain treatment for 2 hr. Interrelations of these results are discussed.抄録全体を表示PDF形式でダウンロード (1242K) -
長澤 貴志, 児島 駿, 木村 英一1982 年 32 巻 1 号 p. 25-33
発行日: 1982年
公開日: 2011/06/07
ジャーナル フリーHydrated and dehydrated red cell samples were prepared from normal human red cells using the antibiotic nystatin. Furthermore, a series of red cell samples exposed to elevated temperature (20-50°C, 10 min) were prepared. The osmotic fragility and deformability of these red cells were then measured, using the coil planet centrifuge system and the capillary tube centrifugal technique, respectively. The osmotic fragility of nystatin-treated red cells decreased and the deformability increased as dehydration of red cells progressed and alternatively, hydrated cells showed increased osmotic fragility and reduced deformability. Red cells exposed to elevated temperatures up to 49°C for 10 min had no changes in mean corpuscular volume or in red cell shape. Above 47°C, however, spectrin extractability progressively decreased and osmotic fragility and deformability decreased. Results suggest that the osmotic fragility and deformability of red cells are interrelated, and are controlled by the geometry of the cell, including the ratio of cell surface area to cell volume and the viscoelastic properties of the membrane.抄録全体を表示PDF形式でダウンロード (4086K) -
蓮尾 博, 時政 孝行, 纐纈 教三1982 年 32 巻 1 号 p. 35-44
発行日: 1982年
公開日: 2011/06/07
ジャーナル フリーAction potentials of the bullfrog atrial muscle, being depressed by carbachol in concentrations of (1-5)×10-7 M, were found to show a slow recovery when application of the drug was sustained. The rate of onset of recovery largely varied depending on individual preparations. The recovery of action potentials was neither due to changes in the ionic distribution across the membrane nor to a secondary action of catecholamine which was released by the nicotinic action of carbachol on sympathetic nerve terminals. These results suggested that the muscarinic ACh receptor responsible for the depression of action potentials showed desensitization to the action of its agonist. The slow inward current recorded by the voltage-clamp experiment showed a decrease and subsequent slow recovery in the presence of carbachol. This suggested that the muscarinic ACh receptor associating with the ionic channel of the slow inward current showed desensitization.
It may be suggested on the basis of these experimental results that 1) the muscarinic ACh receptor of bullfrog atrial muscle may compose a receptor-ionic channel complex (RICC) with voltage-dependent Ca2+channel and 2) the molecular reaction between this RICC and agonist may be comparable to that occurring in the nicotinic RICC of the frog end-plate.抄録全体を表示PDF形式でダウンロード (980K) -
岡嶋 由布子, 赤池 紀扶1982 年 32 巻 1 号 p. 45-54
発行日: 1982年
公開日: 2011/06/07
ジャーナル フリーThe effects of ouabain, Li+, and cooling on the lens fiber potentials in the anterior and posterior sides were investigated in American bullfrog lens mounted in a special holder by using a conventional micropipette technique. Ouabain depolarized the lens fibers in the anterior and posterior sides in a dose- and time-dependent fashion. Similarly, the fibers at both sides were depolarized in Na-free, Li Ringer. The posterior fibers were depolarized faster than anterior ones during exposure to Ringer solution containing ouabain and Li+ The potential difference observed in the lens fibers of the anterior and posterior sides reduced and disappeared during a successive long exposure to ouabain and Li+. It was concluded that in the presence of ouabain and Li+ the transient potential difference between the anterior and posterior lens fibers depends on the anterior epithelial cell layer which delays the penetration of ouabain and Li+ into the lens interior, but not to the difference of total lens surface area in the anterior and posterior exposed to ouabain and Li+. Thermal dependence of the lens fiber potentials at the anterior and posterior sides was 0.78 mV/°C, which is greater than the physical change of 0.2 mV/°C based on the Nernst equation.抄録全体を表示PDF形式でダウンロード (901K) -
松本 光比古1982 年 32 巻 1 号 p. 55-67
発行日: 1982年
公開日: 2011/06/07
ジャーナル フリーγ-Aminobutyric acid (GABA) produces 2 types of hyperpolarizing responses in Aplysia ganglion cells: One is fast and Cl--dependent whereas the other is slow and K+ -dependent. This experiment was performed only on the cells which showed the fast, Cl--dependent receptor activity. GABA-induced increase in membrane conductance (ΔG) was evaluated under the voltage clamp at different potential levels of the resting membrane. The ΔG was found to decrease when the membrane was hyperpolarized. The more the membrane was hyperpolarized, the greater was the decrease. The dose-response curve shifted to the right when the resting membrane was hyperpolarized, a fact suggesting an increase in apparent dissociation constant (Kapparent) of the receptor-GABA complex. In fact, Kapparent increased e-fold for every 11-mV hyperpolarization of the resting membrane. In contrast, neither parameter of other receptor activities, such as the rate of desensitization, the intrinsic activity, and the Hill coefficient, was altered by hyperpolarization of the receptor membrane. It was concluded that the voltagedependent nature observed in this type of GABA receptor might be due to the change in stability of the Cl- -channel in an open state at the receptor membrane.抄録全体を表示PDF形式でダウンロード (1191K) -
Ichiji TASAKI, Kunihiko IWASA1982 年 32 巻 1 号 p. 69-81
発行日: 1982年
公開日: 2011/06/07
ジャーナル フリーBy using both optical and mechano-electric detectors, we have shown that the squid giant axon swells when an action potential is generated. The maximum swelling is reached at the peak of the action potential. The undershoot of the membrane potential is associated with a marked shrinkage of the axon. We have also demonstrated these mechanical changes in axons from which a major portion of the axoplasm has been removed. We have examined the effects of changing the tonicity of the external medium and of applying several chemical reagents.抄録全体を表示PDF形式でダウンロード (1417K) -
勝浦 五郎, 伊藤 眞次1982 年 32 巻 1 号 p. 83-91
発行日: 1982年
公開日: 2011/06/07
ジャーナル フリーIntracerebroventricular (i.c.v.) injection of C-terminal octapeptide of cholecystokinin (CCK-8) in rats prolonged pentobarbitaland ethanol-induced sleeping time, but non-sulfated CCK-8 (CCK-8-NS) had no effect and caerulein showed a tendency to prolong the pentobarbital narcosis. On the other hand, i.c.v. injection of thyrotropin releasing hormone (TRH) shortened the sleeping time and the effect of CCK-8 was apparently antagonized by combined administration of TRH. Spontaneous locomotor activity in the late morning and early afternoon was not affected by CCK-8, but it increased following i.c.v. injection of CCK-8-NS. Hyperactivity produced by TRH and methamphetamine was suppressed by i.c.v. injection of CCK-8, while CCK-8-NS showed a tendency to enhance the methamphetamine-induced hyperactivity and caerulein had no effect. These results indicate that CCK-8 has a sedative action and antagonizes the behavioral excitation caused by TRH and methamphetamine, but that the effects of CCK-8-NS and caerulein were rather the opposite of those of CCK-8. In an additional experiment the TRH-induced body shaking response was not affected by combined administration of CCK-8.抄録全体を表示PDF形式でダウンロード (838K) -
大貫 義人, 中山 昭雄1982 年 32 巻 1 号 p. 93-101
発行日: 1982年
公開日: 2011/06/07
ジャーナル フリーThermoregulatory responses were observed in 7 male subjects during grade walking at different speeds of between 0.5 and 9 km/hr. The total heat productions (H) in uphill and downhill walking are defined as metabolic heat production (M)-external work (W) and M+W, respectively. During 60 min exercise at 20°C, r. h. 40 %, rectal temperature increased to levels dependent on M and independent of H. The sweatrate varied in proportion to H, and not to M. During 10 min exercise, the environmental conditions (28°C, 40 % r.h.) and work intensities were set so that changes in skin temperature could be observed without the interference of sweating. The results indicated that the fall in forearm skin temperature was correlated to M, and not to H. Our previous studies showed that cutaneous vasoconstriction persisted during exercise and that raised work intensities increase the surface area affected by lowered skin temperature. These findings suggest that the rise in core temperature during exercise results from the decreased dry heat loss due to a fall in skin temperature.抄録全体を表示PDF形式でダウンロード (843K) -
Enrique LÓPEZ1982 年 32 巻 1 号 p. 103-119
発行日: 1982年
公開日: 2011/06/07
ジャーナル フリーThe twitch contractions of single fibres from the frog semitendinosus, innervated and denervated, were studied after a brief period (2-3 sec) of conditioning stimulation (CS), at frequencies varying from 1-120/sec. Twitch potentiation was consistently observed in denervated fibres at all rates of CS used. Maximal potentiation was attained within the first 12 sec after the end of CS, which then decayed progressively. The overall duration of the effect, in general, was longer than 5 min. The time course of potentiated twitches was slightly shortened.
Inhibition preceding potentiation was the prevailing effect on innervated fibres under the present conditions. Inhibition appeared either after a short interval (500 msec or less) between the end of CS and the beginning of the subsequent twitch, or after several repetitions of the conditioning schedule. The latter form of inhibition was replaced by potentiation when the corresponding fibres were allowed to rest for 60 min before further conditioning stimulations. Maximal inhibition was attained shortly after the end of CS, which then progressively disappeared. On occasion, inhibition lasted longer than 5 min. The time course of inhibited twitches was slightly enlarged. After fatigue, CS produced twitch inhibition on innervated fibres. In denervated muscles the effect was either potentiation or inhibition. These results are discussed according to the data in the literature.抄録全体を表示PDF形式でダウンロード (1881K) -
吉村 啓一, 根津 恵理子, 千葉 晶子1982 年 32 巻 1 号 p. 121-135
発行日: 1982年
公開日: 2011/06/07
ジャーナル フリーThe role of cyclic AMP in α-amylase release by catecholamines was studied in rat parotid slices. The order of potency required for catecholamines to induce α-amylase release as well as cyclic AMP accumulation was as follows: isoproterenol>norepinephrine=epinephrine>> phenylephrine. At the lowest concentration tested, all of the catecholamines stimulated α-α-mylase release without causing a detectable accumulation of cyclic AMP. High doses of phenylephrine and other derivatives of catecholamines such as salbutamol and soterenol stimulated α-amylase release, but they did not cause accumulation of cyclic AMP and their maximum effects on α-amylase release were significantly lesser than those of norepinephrine. High concentrations of these derivatives decreased the effect of norepinephrine on α-amylase release, which may be attributed to be the cause of this smaller maximum effect. The stimulation of cyclic AMP accumulation by norepinephrine was much more sensitive to inhibition by β-adrenergic antagonists than was the stimulation of α-amylase release by norepinephrine. The effect of norepinephrine on cyclic AMP accumulation was potentiated by isobutylmethylxanthine, which correlated with the degree of inhibition of phosphodiesterase. The effect of low doses of norepinephrine on α-amylase release was increased by isobutyl-methylxanthine, but there was no such effect when either high doses of norepinephrine or dibutyryl cyclic AMP was used. The stimulation of α-amylase release by 1 μm norepinephrine was much greater than that by 0.2 μM norepinephrine plus 0.5 mm isobutylmethylxanthine, while the reverse was took place in cyclic AMP accumulation. Thus, there was a marked dissociation of cyclic AMP accumulation and α-amylase release. The bearing of these results on the role of cyclic AMP in α-amylase release was discussed.抄録全体を表示PDF形式でダウンロード (1337K) -
纐纈 教三, 赤須 崇1982 年 32 巻 1 号 p. 137-140
発行日: 1982年
公開日: 2011/06/07
ジャーナル フリーThe slow inward current, which is carried almost exclusively by Ca2+, was disclosed by voltage-clamp study on bullfrog sympathetic ganglion cells in Ringer solution. This current was confirmed to be markedly depressed by the action of adrenaline, suggesting that adrenaline modulates the Ca2+ influx of ganglion cells under physiological conditions.抄録全体を表示PDF形式でダウンロード (384K) -
北村 潔和, 萩行 健一, 山地 啓司1982 年 32 巻 1 号 p. 141-144
発行日: 1982年
公開日: 2011/06/07
ジャーナル フリーFinger blood flow (FBF) was measured with mercury-insilastic strain gauge venous occlusion plethysmography before, during and after 2-min leg exercise on a Monark bicycle ergometer at exercise intensities of 0, 60, 90, and 120 watts. The FBF rapidly decreased in all subjects immediately after the onset of exercise, and was as maintained at low levels during exercise. The amount of decrease in FBF observed during exercise seemed to be independent of exercise intensity.抄録全体を表示PDF形式でダウンロード (310K) -
伊藤 眞次, 勝浦 五郎1982 年 32 巻 1 号 p. 145-148
発行日: 1982年
公開日: 2011/06/07
ジャーナル フリーCholecystokinin octapeptide (CCK-8) did not affect the behavioral syndrome of rats treated with pargyline and 5-hydroxytryptamine, while TRH produced a marked behavioral excitation under the same condition. However, the serotonin-potentiating effect of TRH was apparently suppressed by simultaneous administration of CCK-8.抄録全体を表示PDF形式でダウンロード (356K) -
林 正男, 永坂 鉄夫1982 年 32 巻 1 号 p. 149-152
発行日: 1982年
公開日: 2011/06/07
ジャーナル フリーAcute hypoxia (9.5% O2) increased the heart rate (HR) in hypoxia (12% O2 for 2 months)-acclimated (HX) rats, while it decreased HR in unacclimated (CT) rats. After treatment with propranolol, acute hypoxia decreased HR to the same extent in CT and HX rats. After treatment with atropine, acute hypoxia increased HR in HX rats but not in CT rats. The hypoxia-induced tachycardia in HX rats may be mainly due to an enhanced sympatho-adrenal activity.抄録全体を表示PDF形式でダウンロード (375K)
- |<
- <
- 1
- >
- >|