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Volume 26 (1976)
- Issue 6 Pages 577-
- Issue 5 Pages 441-
- Issue 4 Pages 345-
- Issue 3 Pages 235-
- Issue 2 Pages 101-
- Issue 1 Pages 1-
Volume 26, Issue 4
Displaying 1-9 of 9 articles from this issue
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Yoshifumi TANAKA, Taketoshi MORIMOTO, Hiroshi WATARI, Masao MIYAZAKI1976 Volume 26 Issue 4 Pages 345-353
Published: 1976
Released on J-STAGE: June 07, 2011
JOURNAL FREE ACCESSThe relationship between the hematocrit value and the absolute value of impedance of whole blood was analyzed.The results indicated that the hematocrit value was linearly proportional to the logarithm of the impedance of whole blood over the range of hematocrit values of 10 to 60% with a correlation coefficient of 0.995. The circuit used for detection of the impedance of whole blood was described. It required no adjustments during measurements and had a wide linear range. The sources of error during continuous measurements were the rate of blood flow through the sensor cell, the temperature of the blood, and the concentrations of plasma proteins and ions. Accordingly, the flow and temperature of blood were kept constant during measurements. Changes in the concentrations of plasma proteins and ions within physiological ranges caused errors of ±2.0%. Typical results of continuous measure ments were presented, showing that the hematocrit values obtained by this method agreed well with those obtained by the conventional method from the packed cell volume.An advantage of this method over the conventional method was that it could follow rapid and transient changes in the hematocrit.View full abstractDownload PDF (722K) -
Takanori FUJII, Kazuo YOSHIZAKI1976 Volume 26 Issue 4 Pages 355-365
Published: 1976
Released on J-STAGE: June 07, 2011
JOURNAL FREE ACCESSThin slices, 500μm in thickness, prepared from the guinea pig olfactory cortex and maintained in vitro, generate presynaptic and postsynaptic potentials following electrical stimulation of the lateral olfactory tract. These responses, however, cannot be elicited immediately after slice preparation;they start to develop gradually as the incubation continues. It was found that there was a remarkable time lag for the development between the pre- and the postsynaptic potentials. The presynaptic potential appeared early and developed its maximum height within 10 to 20 min from the onset of incubation. This time course was only slightly influenced by low temperature. Development of the postsynaptic potential in incubation was delayed and the time required to obtain the maximum height was about 30 min at 37°C and 70 min at 22°C. Upon step-like warming from 24°C to 37°C, there was a rapid increase in the amplitude of the response. In the glucose-deficient solution the presynaptic potential maintained its amplitude longer than the postsynaptic potential. Frequency potentiation of the postsynaptic potential was studied by applying a train of six stimuli. The maximum augmented ratio among six responses was the highest in early incubation and reached a steady at 50min. The ratio of the post-tetanic potentiation of olfactory neurons was the highest at 5 min incubation and reached a steady at 20 min.View full abstractDownload PDF (1102K) -
Tetsuo NAGASAKA, Nobumitsu SHIMADA, Kazuko NISHIKURA1976 Volume 26 Issue 4 Pages 367-374
Published: 1976
Released on J-STAGE: June 07, 2011
JOURNAL FREE ACCESSVascular and lipolytic responses to intravenously administered norepinephrine (NE, 1μg/kg·min for 30 min) were examined in autoperfused canine subcutaneous and omental adipose tissues. In response to NE, arterial perfusion pressures increased initially and then returned gradually to the pre-infusion levels. Shortly after the onset of NE infusion, the blood flow increased greatly in both adipose tissues. The higher blood flow was maintained throughout the whole infusion period in the subcutaneous adipose tissue, whereas in the omentum the initial high flow fell gradually to the pre-infusion level. Vascular resistance started to decrease after 2-5 minfrom the onset of NE infusion in the subcutaneous adipose tissue and the reduction of resistance was consistent and persistent as the infusion continued.NE infusion increased the net output of FFA from the subcutaneous adipose tissue, but not in the omentum. The increased FFA output seemed to coincide with the decrease in vascular resistance.Omental adipose tissue may not be influenced by NE at the concentration tested in this experiment. A marked fall in the blood flow was observed in the hindleg of the same animals. Such fall in blood flow was not observed in the adipose tissues in this experiment. It was concluded from the present results that there was a qualitative difference in the effects of norepinephrine on adipose tissues from different locations in the same animal and lipolytic response occurred only if active vasodilatation was present in these tissues.View full abstractDownload PDF (921K) -
Takehiko OCHIAI, Yasunori ENOKI1976 Volume 26 Issue 4 Pages 375-384
Published: 1976
Released on J-STAGE: June 07, 2011
JOURNAL FREE ACCESSIn the blood stored in acid-citrate-dextrose solution (ACD blood), the oxygen affinity and red cell 2, 3-diphosphoglycerate (2, 3-DPG) content showed parallel exponential decays with half-lives of 3 to 4 days. In the blood stored in citrate-phosphate-dextrose solution (CPD blood), the two parameters increased during the first 4 days before showing the same decay as that seen in the ACD blood. There was no significant change in the transmembrane pH gradient of the red cells, and thus the intracellular pH at the plasma pH of 7.40 was always in the range of 7.17±0.02 throughout the period of storage in ACD medium. In both ACD and CPD blood, the Hill exponent n was always normal (-2.8) while the Bohr coefficient (Δlog P50/ΔpH) rose along with the lapse of time for preservation. The oxygen affinity of the CPD blood was less influenced by the red cell 2, 3-DPG than was that of the ACD blood. This phenomenon was thought to derive from higher concentration of salts within the CPD-stored red cells. The efficiency of blood oxygen transport in ACD and CPD blood was compared.View full abstractDownload PDF (923K) -
Isao OOTA, Torao NAGAI1976 Volume 26 Issue 4 Pages 385-394
Published: 1976
Released on J-STAGE: June 07, 2011
JOURNAL FREE ACCESS45Ca influx in the intact, the T-disrupted, and the urea-treated or Mn++-treated frog sartorius muscles was measured at rest and during potassium contracture. In the intact muscle, Ca influx increased with the increasing of potassium concentration in the bathing solution, and the time course of the Ca influx showed considerable correspondence with that of the potassium contracture. This increased Ca influx was divided into two components: early rapid Ca influx and late slow Ca influx. The amount of early rapid Ca influx at higher concentrations of potassium occupied about 60% of the total Ca influx. The early rapid Ca influx markedly decreased in the T-disrupted and in the urea-treated or Mn++-treated muscles. On the other hand, the late slow Ca influx and the resting Ca influx in these muscles changed only slightly. These results suggest that the early rapid Ca influx occurs mainly through the membrane of the T-system, particularly at the triadic junctional area of muscle fiber, while the late slow Ca influx and the resting Ca influx occur mainly through the surface membrane.View full abstractDownload PDF (1147K) -
T. F. HUANG, Y. I. PENG1976 Volume 26 Issue 4 Pages 395-401
Published: 1976
Released on J-STAGE: June 07, 2011
JOURNAL FREE ACCESSResponses in heart rate and blood pressure to the dive in unanesthetized rats were studied by submersion of the head in water for 30 sec. During the dive, remarkable bradycardia developed and blood pressure was slightly elevated. Bilateral section of the carotid sinus nerves or selective destruction of the carotid body chemoreceptor by intrasinusal injection of acetic acid attenuated the bradycardic response to the dive, while section of the recurrent nerves or section of the sympathetic trunks at the cervical level together with the superior laryngeal nerves had no effect. These data indicate that the chemoreceptor plays an important role in diving bradycardia in rats.View full abstractDownload PDF (6614K) -
Tatsuhiko KAWARABAYASHI, Takuro OSA1976 Volume 26 Issue 4 Pages 403-416
Published: 1976
Released on J-STAGE: June 07, 2011
JOURNAL FREE ACCESSComparative effects of noradrenaline (10-8-10-6g/ml) and isoprenaline (10-10-10-6g/ml) on electrical and contractile activity were investigated in longitudinal and circular muscle strips of rat myometrium (13-19days pregnant). When recorded with an intracellular microelectrode, spike potentials of longitudinal muscle discharged spontaneously in bursts. Treatment with either noradrenaline or isoprenaline hyperpolarized the membrane and increased membrane conductance, causing the cessation of spontaneous activity. Slow potential was dominant in the circular muscle, and it became prolonged after treatment with noradrenaline, leading to an increase in tension. Isoprenaline reduced the duration of the slow potential and depressed the contraction. The minimal concentration of isoprenaline needed to suppress the spontaneous activity in circular muscle was much higher than in longitudinal muscle.
The excitatory effect of noradrenaline on circular muscle was antagonized by treatment with phentolamine, and the inhibitory effect of catecholamines on both longitudinal and circular muscles by propranolol.α-Adrenoceptor appears predominant in circular muscle, while β-adrenoceptor in longitudinal muscle in rat myometrium during late-pregnancy.View full abstractDownload PDF (1615K) -
Moto MATSUMURA1976 Volume 26 Issue 4 Pages 417-426
Published: 1976
Released on J-STAGE: June 07, 2011
JOURNAL FREE ACCESSCrayfish muscle fiber responded to 1-4mM caffeine with repetitive contractions. At 4mM caffeine, two to four peaks with intervals of 2-3 sec were observed in the tension curve. At 2mM caffeine, the intervals were prolonged so that the second contraction started after the first contraction ceased. The tension in the second contraction was slower and smaller than the first one. At 1mM caffeine, very small tensions developed repetitively at intervals of about 1 min and lasted for more than an hour. The time courses of these caffeine contractions were not modified by the current flow in the direction of hyperpolarizing a major part of the muscle membrane. It was observed under a microscope that the contraction in caffeine solution was induced asynchronously. Moreover, repetitive contractions occurred at several sites and propagated in the longitudinal direction of the muscle fiber. The propagation velocities of contraction waves were between 330 and 40μEm/sec depending on the time after perfusion with caffeine solution.View full abstractDownload PDF (5425K) -
Yasunobu OKADA, Akihiko IRIMAJIRI, Akira INOUYE1976 Volume 26 Issue 4 Pages 427-440
Published: 1976
Released on J-STAGE: June 07, 2011
JOURNAL FREE ACCESSThe water content (V) and the concentrations of K+, Na+, and Cl-in the epithelial cells of rat small intestine ([K]i, [Na]i, and [Cl]i) were measured in high K+ media and in the presence of glucose or glycine (20mM). Raised external K+ concentrations brought about increases in V. Parallel with swelling of the cell, increases in [K]i and [Cl]i and decreases in [Na]i were observed. Such a pattern of changes in [K]i, [Na]i, and [Cl]i was concordant with that expected from the K+-induced depolarization and the permeability properties of the cell membranes. In the presence of D-glucose or glycine, remarkable increases in V were observed, which resulted in concomitant decreases in [K]i, [Na]i, and [Cl]i. Assuming the osmotic balance between intra-and extracellular fluids, the concentrations of accumulated solutes within the cell as well as the net gain of these ions were estimated. The results demonstrated that the accumulated solute was in an osmotically active form, resulting in cell swelling with concomitant decreases in [Cl]i, while the net gain of Na+ and K+ in the cells occurred despite apparent decreases in [Na]i and [K]i.View full abstractDownload PDF (1382K)
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