The Japanese Journal of Physiology
Print ISSN : 0021-521X
Volume 23, Issue 4
Displaying 1-5 of 5 articles from this issue
  • Shinkuro IWAHARA, Hiroshi OISHI, Katsunori SANO, Kwo-Man YANG, Toshiak ...
    1973 Volume 23 Issue 4 Pages 361-370
    Published: 1973
    Released on J-STAGE: June 07, 2011
    JOURNAL FREE ACCESS
    The electrical activity of the olfactory bulb (OB) was first clearly observed around 5 days after birth in albino rats it generally consisted of (a) rhythmic “induced” waves, appearing in bursts after inspiration, and (b) “intrinsic” waves of lower amplitude and fast frequency, occurring independently of nasal air flow. The first cortical activity was also observed around the same time, and was very similar to the OB activity, especially to the induced waves. This similarity, however, diminished daily as the rats grew. In adult rats, little correspondence between the two structures was found.
    A series of experiments suggested the dependence of the cortical activity upon OB induced waves because (1) the latter activity occurred with an almost fixed temporal relation to the former, (2) both cortical and OB activities were simultaneously enhanced in amplitude by (a) strong olfactory stimulation with amyl acetate or xylene as well as (b) higher doses (20 mg/kg) of pentobarbital injected intraperitoneally (i. p.), and (3) the cortical rhythmic activity, appearing in synchrony with the OB induced activity was almost completely abolished (a) when the inspired air was made to by-pass the nasal cavity and (b) after the OB was removed bilaterally.
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  • Kunio SUGIHARA, Jiro GOTOH
    1973 Volume 23 Issue 4 Pages 371-379
    Published: 1973
    Released on J-STAGE: June 07, 2011
    JOURNAL FREE ACCESS
    Spontaneous EEG activities of the hyperstriatum accessorium, archistriatum, paleostriatum augmentatum and primitivum, dorsal and ventral hippocampus, area entorhinalis, area paraentorhinalis, and optic tectum were recorded simultaneously in unanaesthetized chickens during sleep and wakefulness and subjected to frequency analyses. The results obtained are as follows.
    1. No regular slow waves such as seen in the hippocampus of mammals during arousal and paradoxical sleep were observed in the hippocampus of chickens.
    2. No high-voltage fast waves appeared in the archistriatum during arousal.
    3. Regular alpha-like waves of 8-13 Hz appeared in the paleostriatum primitivum during slow-wave sleep.
    4. In association with rapid eye movements, monophasic spikes were recorded in the optic tectum of chickens during the paradoxical-sleep phase.
    5. Frequency analyses revealed that the EEGs of the hyperstriatum accessorium of chickens during arousal and paradoxical sleep contained more developed components of slow waves than in the EEGs of the neocortex of mammals.
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  • I. ANALYSIS OF THE FIELD POTENTIALS
    Toshio SHIMONO
    1973 Volume 23 Issue 4 Pages 381-400
    Published: 1973
    Released on J-STAGE: June 07, 2011
    JOURNAL FREE ACCESS
    1) A controversial problem on the inhibitory mechanism in the frog cerebellar cortex was brought to a conclusion by studying cortical field potentials generated by double and combined stimulation of the parallel fiber (Loc) and the white matter (WM).
    2) Depth profiles of the field potentials elicited by Loc and WM stimulations were essentially similar to those found in other vertebrates.
    3) The field potentials representing antidromic and orthodromic activations of Purkinje cells were inhibited for a period of 100-400 msec by conditioning Loc stimulation. The same was observed by conditioning WM stimulation which was made intense to involve activation of the mossy fiber-granule cell system and climbing fibers.
    4) The field potentials of granule cell discharges elicited by WM stimulation were also suppressed for a period of 200-400 msec by conditioning Loc stimulation.
    5) It is concluded that two inhibitory mechanisms operate in the frog cerebellar cortex: stellate cell inhibition of Purkinje cells and Golgi cell inhibition of granule cells.
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  • Takuro OSA
    1973 Volume 23 Issue 4 Pages 401-417
    Published: 1973
    Released on J-STAGE: June 07, 2011
    JOURNAL FREE ACCESS
    Effects of [K] 0 and [Na] 0 on isometric contraction of mouse myometrium were investigated in combination with the use of low temperature and Mn. Membrane activity was recorded by the sucrosegap method or with microelectrodes, and contraction by strain gauge transducer.
    1. A sudden increase of [K] 0 from the 5.6 mm contained in normal Locke solution to more than 40 mm caused a quick rise of tension to a maximal level (phasic response), which was followed in about 5 min by incomplete relaxation (tonic response). The magnitude of tonic response changed depending on [Ca] 0.
    2. Contraction was elicited by applying Ca to the solutions containing various [Na] 0 and [K] 0, after the muscle had been relaxed in Ca-free isotonic K solution. In the Na-containing solution, where [Na] 0 was decreased by replacement with the same amount of [K] 0, the contraction was maximal in about 30 mm [K] 0. In the Na-free solution containing various [K] 0, where the osmolarity was kept constant by the substitution of Tris for Na, the contraction decreased with increasing [K] 0. Lowering temperature from 32° to 16°C caused the contraction in Na-containing solution to increase but had little affect on that in Na-free solution.
    3. Treatment with 2 mM Mn caused a potentiation of tonic response of K-contracture, whereas the phasic response was depressed. As the Mn was washed out with normal Locke solution after the pretreatment with 2 mM Mn for 30-60 min, tonic response became more potentiated for several hours. During this period, the effect of [Ca] 0 on the K-contracture was investigated.
    4. The change in membrane potential in response to a 10-fold change of [K] 0 was 35 mV for Na-containing and 10 mV for Na-free solution. Lowering the temperature from 32° to 18°C caused a depolarization of 15 mV in normal Locke solution.
    Several smooth muscles produce contracture when immersed in external media with modified ionic compositions, such as those with excess K or those without Na, which is replaced by Li, choline, or sucrose (for review, see BOHR 1964; EVANS et al., 1958; JUDAH and WILLOUGHBY, 1964; IMAI and TAKED 1967; REUTER and BLAUSTEIN, 1972). Previous studies indicate that, apart from effects on the membrane potential, these external media modify the Ca transport across the membrane and change intracellular Ca concentration, which triggers the contractile mechanism of the tissue (REUTER and SEITZ, 1968; BLAUSTEIN and HODGKIN, 1969; KATASE and TOMITA, 1972).
    The mouse myometrium was shown to exhibit contracture in low Na solution and a much smaller contracture in isotonic K solution (OSA, 1971, 1973a, b). In the present experiments, the contractile effects of [Na] 0 and [K] 0 were investigated in combination with the use of low temperature and Mn. Also studied was the possibility that a reduction of [Ca] 1 in mouse myometrium depends on the Nadependent Ca exchange on one hand, and on Ca-sequestering to some inner membrane site on the other, the mechanism of which appears to be depressed by the treatment with Mn. By contrast, it was argued that external K is largely responsible for modifying the influx of Ca.
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  • Yoshitaka SAITO, Takeshi HOSHI
    1973 Volume 23 Issue 4 Pages 419-434
    Published: 1973
    Released on J-STAGE: June 07, 2011
    JOURNAL FREE ACCESS
    Isolated small intestines of toads were mounted in a flux chamber or suspended from a cannula as an everted sac, and osmolarity of solutions bathing the mucosal surface was changed by adding Dmannitol or polyethylene glycol to the standard solution. With increase in osmolarity we observed increases in (1) resistance of transmural water flow, (2) transmural electrical resistance, (3) tissue electrolyte content, (4) a decrease in water content of the tissue, (5) a change in transmural potential difference in the direction that the mucosal side becomes more positive, and (6) a reduction in size of the glucose-evoked potential. On the other hand the tissue uptake of D-glucose and Dgalactose from the mucosal solution did not significantly change with the treatment. Within a range of osmolarity change (less than 200 mOsm/liter), results (3) and (4) can be interpreted as due to a mere withdrawal of water from the tissue. The relationship between the size of the osmotic potential change and the osmolarity difference was similar to that between the rate of net water flow and the osmolarity difference. The fact that mucosal hyperosmolarity exerts strong influence on the sugarevoked potential but no significant influence on the uptake of sugar is interpreted as the effect of the hyperosmolarity being a consequence of changes in electrical resistance representing the lateral intercellular space.
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