An electric method for recording changes in volume of body and organs is described. The object is inserted between a pair of electrodes, or insulated thin aluminum leafs are sticked on the surface of body, and changes of effective electric capacitance of condenser made up by these electrodes are measured by an electronic method with high sensitivity and stability. Several illustrative examples are shown.
This method “electrocapacitography (ECPG)” may be applied widely for recording changes in volume or movements of various organs or parts of the body.

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An experiment was carried out aiming at the detection of thyroxine-α-ketoglutaric transaminase in rat kidney. Radioactive thyroxine was incubated with rat kidney homogenate and the production of tetraiodothyroacetic acid (TA₄) was measured. The production of this derivative at the expense of thyroxine was of the same amount under anaerobic conditions as under aerobic conditions. The addition of the co-enzyme of transaminase, pyridoxal phosphate, caused a considerable increase and that of α-ketoglutarate a marked increase in the production of TA₄. When these two substances were absent, TA₄ was not, or only slightly, produced. These results offer reliable evidence for the presence of transaminase acting upon thyroxine in rat kidney.

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Homogenates of liver and kidney of rats showed potent activity in inactivating vasopressin during in vitro incubation, while those of brain tissue had no activity. When pyridoxal was added into the incubation medium at pH7.2, brain homogenate did inactivate vasopressin. The effect was marked in hypothalamus homogenate, slight in brain cortex homogenate, and moderate in whole brain homogenate.
Homogenates of liver taken from adrenalectomized rats showed considerably decreased activity. The activity of hypothalamus homogenates was not significantlyaffected by adrenalectomy.
Vasopressin inactivated by hypothalamic tissue in the presence of pyridoxal was not dialyzed against distilled water. Inactivation of vasopressin by hypothalamic tissue was reversible: Inactivated hormone restored its antidiuretic activity by acetic acid extraction.

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(1) The denervated jejunal loop of dogs are orthodromically as well as antidromically perfused with various solution, pressure gradient being increased gradually under various constant outflow pressures to elucidate the role of the mucosal reflex for transport of the intestinal contents.
(2) In the orthodromic perfusion with 0.9 per cent NaCl solution the outflow volume of fluid which is propelled by an orthodromic contraction wave increases gradually with a rise of the pressure gradient, until it finally becomes continuous. The course of the outflow changes with a change of outflow pressure: With a rise of the outflow pressure the outflow threshold is gradually so lowered that the outflow occurs even at the reverse gradient and then the threshold is raised again, while the flow of fluid is, in this case, steadily retarded.
(3) When the loop is perfused orthodromically with N/80 hydrochloric acidsaline solution the outflow threshold is lowered, while the flow of fluid is remarkably retarded in comparison with those in the perfusion with saline solution. There can be also noted a remarkable rise of tone of the loop.
After administration of xylocaine or C6 the threshold is raised and the flow is accelerated, the gradient-outflow diagram taking a linear course.
(4) In the antidromic perfusion, with a rise of outflow pressure there occurs a remarkable rise in the tone of the loop, especially in a higher degree at its oral end and the outflow threshold is so elevated that the outflow stops even at moderate pressure gradient. The outflow begins at the gradient much higher than that in the orthodromic perfusion; the outflow volume increases with a further rise of the gradient, until the gradient reaches a certain critical one and then it diminishes. Despite the antidromic perfusion, the direction of the contraction wave is the orthodromic. When xylocaine or C₆ is administered, the outflow takes a course entirely similar to that in the orthodromic perfusion of the loop treated with the same chemicals as mentioned above.(5) Before and after administration of xylocaine or C₆ the individual contraction wave is essentially unchanged in its nature, being capable of propelling the fluid.
(6) It may be concluded from the findings described above that the mucosal reflex does not elicit any contraction which is characteristic in forcing the intestinal content but regulates both the direction of propagation and the strength of the contraction wave which occurs inherently.

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The effects of aconitine upon the cardiac membrane potential were investigated on the ventricular muscle of the dog by means of the intracellular microelectode technique.
Aconitine produces ectopic, spontaneous and repetitive activity of the cardiac cell on which it acts. By recording the changes in membrane potential throughout the whole course from the moment of application of the drug until the onset of the spontaneous activity of the induced pacemaker, it has been confirmed that aconitine makes manifest, and enhances the latent tendency of the cell to have an oscillatory potential following the spike, and that the oscillatory swing touches off the spontaneous spike after having been augmented to a definite critical level by repeated excitaions. At least several drives have to be given consecutively before the enhanced oscillatory potential attains to the critical level.
In the ordinary pacemaker cell of the heart which is functioning as such, aconitine accelerates progressively its spontaneous slow depolarization, and produces extremely rapid tachycardia, flutter and fibrillation.
Ca and Mg ions counteract the aconitine action. At concentrations higher than normal, both of these ions inhibit or prevent the spontaneous activity due to aconitine.
The implications of these effects of aconitine in the mechanism of production of the spontaneous activity of the natural pacemaker cells are discussed.

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1. The constant current running across the human retina from outside into inside of the eyeball (polarizing current with “cornea cathode”) brings about an enhancement of ERG, i. e., an increase in amplitude of b-wave and an decrease in its latency, while the current of the reverse direction (“cornea anode”) causes its depression, i. e., a decrease in amplitude of b-wave and an increase in its latency.
2. Both of the enhancement and the depression of ERG depend not only upon the intensity of the polarizing current but also upon the intensity of the stimulus (white light). When the light intensity is kept constant, both changes in amplitude and latency of b-wave due to polarization are approximately in a linear relation to the intensity of the polarizing current.
3. The visual sensitivity of the fovea centralis to the white light improved also with increase in intensity of the polarizing current with “cornea cathode”, while it weakens with increase in intensity of the current with “cornea anode”. These results are quite similar to the changes in cone sensitivity to orange-red spectral rays in Kravkov and Galochkina's experiments.
4. The effects of polarization on the visual mechanism were proved consistently by two different methods of electrophysiological and psychophysical experiments.

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1. In hydrated rats the rate of water excretion increased on exposure to cold. Antidiuretic effect of Pitressin was significantly diminished in a cold atmosphere.
2. In hydrated rats administrations of epinephrine, norepinephrine and hydrocortisone resulted in an increase of urinary excretion of water and countervailed antidiuretic effect of Pitressin. ACTH showed similar effect. DOCA and cortisone were without effect.
3. In adrenalectomized and hypophysectomized rats cold exposure did not cause any increase in water excretion, while adrenal demedullated rats and thyroidectomized rats showed an increased water excretion on exposure to cold.
4. It was concluded that the secretion of the adrenal cortex participates in bringing about the increased water elimination on exposure to cold.

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1. On the toad's limb muscles such as sartorius, iliofibularis, gracilis, glutaeus magnus, adductor magnus and gastrocnemius, the motor end-plate zone was determined by means of analysing action potentials led by a septal method. For stimulation of the nerve, isotonic citrate solution was applied to the desheathed nerve or injected into the nerve trunk.
2. In these muscles a great majority of end-plates generating propagated muscle impulses was concentrated to one or two zones within a few mm. from its nerve entry.
3. The site of origin of BFT impulses was also investigated by the similar means. In ordinary condition, the site situated at a band rather distant away from the end-plate zone.
4. The site of origin was shifted from the original site and approached towards the end-plate zone by raising or lowering of fluid temperature from optimum which varied according to the seasons.
5. Also shift of pH from the optimum, about 7, got the site of origin approach the end-plate zone.
6. On decreasing the saline concentration, the osmotic pressure being compensated by adding glucose solution, the site of origin was shifted towards the end-plat zone with decreasing of saline concentration.
7. These environments inadequate for the fibrillating muscle made the site of origin shift towards the end-plate zone, finally getting to the latter.
8. The shift of the site of origin of BFT, the relation between its site and the end-plate and distribution of motor end-plates were discussed.

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In this experiment the functional relations of the mesencephalic and bulbar motor nucleus of the trigeminal nerve and the hypoglossal nucleus were analized electrophysiologically.
1. By jaw depression, background activities of the mesencephalic nucleus and bulbar motor nucleus of the fifth nerve were accelerated simultaneously, but conversely that of the hypoglossal nucleus was inhibited reciprocally.
2. There were characteristic projections of the spindle afferent of each masticatory muscle in the trigeminal motor nucleus, and presumably in the mesencephalic nucleus. The spots of the masseter and temporalis were in the more rather rostral part and that of the occipito-mandibularis was situated in the caudal part of the nuclei than the former two.

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The effect of the systemic application of GABA on blood pressure was more or less dual in the rabbit, the dog and the cat. Its depressant action was the strongest in the rabbit and the weakest in the cat. On the contrary, its pressant effect was observed most obviously in the cat and most obscurely in the rabbit. In the dog, both effects were likewise middle between these two species, although the depressant effect was observed more easily.
Although the mechanism of the pressant effect of GABA was not so completely investigated, the rise of blood pressure by GABA appeared to be due to its action on the higher central nervous system, because it was reduced with anaesthesia or completely disappeared after decerebration.

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Systemic GABA caused a fall in blood pressure, some changes in respiration and facilitation on the flexor reflex. Further, it could facilitate knee jerk under some suppressive condition (for example, chlorpromazine-poisoning).
The site of action of GABA on the spinal reflex was also in the brain stem.
The authors assume that systemic GABA has a specific affinity to the re ticular system and it is not a mere inhibitory substance in the mammals.

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Microelectrode experiments were made on two kinds of cortical cells in the cat, each identified by antidromic stimulation. First, recordings were made from callosal neurons, and these were studied by radial nerve stimulation. Second, recordings were made from pyramidal tract cells (P. T. cells), and the effects of corpus callosum stimulation on the activities of P. T. cells were studied. All studies were carried out in the pericruciate cortex. The following results were obtained;
1) Out of 20 cells identified as callosal neurons, 12 were fired by single stimuli delivered to the superficial radial nerve. The latency of the discharge ranged from 12 to 20msec.
2) Single stimuli to the corpus callosum produced long lasting inhibitory effects on P. T. cells. The inhibitory effect seemed to start with a latency of 20 to 30msec. Though with most cells the effect was purely inhibitory (table 1), on rare occasions a transitory excitation preceded the inhibition.
3) In a few successful intracellular recordings from P. T. cells, a marked hyperpolarization of the membrane was observed to occur when firing was inhibited.

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1. The miniature electrical oscillation of the tymbal muscle of the cicada was investigated with the following species: Terpnosia vacua, Platypleura kaempferi, Cryptotympana japonensis, Graptopsaltria nigrofuscata, Tanna japo-nensis, Oncotympana maculaticollis and Meimna opalifera.
2. The miniature electrical oscillation was observed not only in the silent muscle but also in the shrilling muscle. It was observed either in situ or in isolated preparation.
3. The miniature electrical oscillation was not affected by motor innervation but originated myogenically.
4. The pattern of oscillation was usually irregular but sometimes changed to be regular, waxing and waning.
5. The frequencies of two sources which were supposed to compose the beating oscillation were approximately equal to that which was found when the wave was regular.
6. The frequencies of regular and beating discharges were quite comparable to that of the action potentials of respective species in singing.
7. The cause of the transition of the pattern of oscillation was discussed and its similarity to the electrocardiogram of the fibrillation was noticed.

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1. The ventral root reflex potential monosynaptically provoked by a single shock stimulus to a nerve branch of the quadriceps muscle or the gastrocnemic muscle in the cat chronically spinalized (at the level of Th₁₀) is irregular in its shape and is prolonged in its discharge duration.
2. The reflex response led off from a unitary nerve fiber in the ventral root consists of a train of repetitive spikes.
3. Temporal pattern of the unitary repetitive spike discharge differs from motoneuron to motoneuron in latency, mean discharge frequency, discharge duration, threshold and susceptibility to various stimulation intensities, and is classified into two types, i. e., the rapidly responding type and the slowly re-sponding one.
4. The site responsible for the change of the reflex potential may be the synaptic region or the motoneuron itself in the spinal cord, since the shape of nerve action potential recorded at the entrance of a dorsal root into the cord is exactly identical with that recorded in the intact animal.

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(1) The discharge patterns during strychnine tetanus of the spinal frog were investigated for the purpose of analysing the origin of rhythmic activity.
(2) Normal discharge pattern was initially a continuous type of enormous irregular impulses, which later turned into a periodic type of grouped impulses with regular rhythm.
(3) The regular discharge patterns recorded simultaneously from two differ-ent points in the spinal cord or two different muscles showed that the impulses in both records did not begin to fire at the same time, but they ceased to fire at the same instant in all of two corresponding groups of impulses.
(4) The tetanic impulses never spread electrotonically through the tran-section of spinal cord from one side to the other.
(5) There was no tendency to make rhythm in the part of spinal cord above 3rd intervertebra or below 5th intervertebra.
(6) Afferent impulses through skin nerve could reset or inhibit the rhythm.
(7) The possibility of the circuit movement, involving the inhibitory inter-neuron with many collaterals for motoneurons was discussed as the origin of autorhythmicity.

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