1. In order to measure changes in the transretinal dc potential and the ERG, the isolated bullfrog's retina deprived of the pigment epithelium placed as a septum separating the modified Conway solution in the apparatus.
2. From diffusion potentials between non-identical solutions, the relative permeability coefficients were: P_Na: P_K: P_choline P_Cl: P_SO4=0.33: 1.00: 0.27: 0.29: 0.11.
3. The ‘half-times’ of the diffusion potential transients produced due to increasing the potassium concentration was 2.2 times longer for the vitreous surface than for the receptor surface. This suggests that the vitreous surface has a indiscriminate retarding force to potassium diffusion.
4. Low sodium or high potassium solution on the receptor side induced the reduction in the ERG, while no change on the vitreous side. The reduction in the ERG with a low sodium solution related to the log of the sodium concentration.
5. Decreasing chloride concentration on the receptor side to 15 or 0 mM, the amplitude of the ERG was reduced, whereas on the vitreous side it was increased. These light responses could be due to a direct effect of lack of chloride in the bathing solution rather than to a reduction of calcium ions or the effect of polarizing current across the retina.
6. High potassium solution, azide or ouabain on the receptor side causedspontaneously a slow oscillatory dc potential change resembling Leão's spreadingcortical depression, whereas when either one side of the retina was exposedto a low chloride solution, the slow oscillatory potential induced following alight stimulation. On the basis of these results it is proposed that the slowoscillatory potential is the response of the scleral portion of the MÜLLER cells.

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In the present experiment, the physiologic role of the baro-receptive information from the submandibular gland was studied in the dog. Backpressure was applied to the unilateral submandibular duct of the anesthetized dog. The pressure-curve and venous out-flow from the submandibular gland and the electro-salivogram of the gland were recorded simultaneously.
Venous out-flow from the gland was distinctly increased by a back-pressure application of 40-60mmHg to the duct of the gland. However, the electrosalivogram was not distinctly affected by this procedure. This blood-flow increasing response was elicited only in the ipsilateral gland and not in the contralateral side. The blood-flow increasing response was completely abolished by dissection of the ipsilateral chorda tympanic nerve, but not by dissection of the cervical sympathetic nerve to the gland.
The present results imply that baro-receptors in the submandibular gland of the dog play some important physiologic role in regulating the blood supply of the gland, and also suggest that the response has a possibility to promote the recovery process of the activated cells.

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1. The effects of alternating current on pace-maker activity have been studied. in the isolated toad sinus venosus. The alternating current produced an immediate action followed by an after-inhibition and an after-augmentation.
2. The immediate action of stimulation by voltages less than 1.7V/cm was an acceleration of the rhythm and a depression of the contractile tension, while voltages of 1.7-5.0V/cm caused an irregularity in rhythm and tension. The voltage range in which the irregularity was obtained was lowered by acetylcholine and elevated by atropine.
3. A further increase in stimulation voltage produced, during current flow, a sustained contraction which increased linearly with voltage increase up to 150% of the peak tension of normal phasic contraction. The sustained contraction appeared even after the elimination of membrane excitability by procaine or by complete lack of external sodium ions, and hence it was thought to be a direct response of the intracellular elements.
4. The first after-effect was an inhibition of both pace-maker rhythm and contractile tension, which appeared prominent at higher voltage of stimulation. The inhibitory effect was strengthened by both acetylcholine and physostigmine, and blocked dramatically by atropine.
5. The second after-effect was an acceleration of the pace-maker rhythm and a potentiation of contractile tension. The potentiation appeared frequently separated into three phases, the fast, middle and slow phases. Dichloroisoproterenol and reserpine blocked the acceleration and eliminated the middle and slow potentiations. Cocain, on the other hand, abolished the fast and middle potentiations after a temporal enhancement of all phases.
6. The after-effects of mass stimulation, therefore, are attributable mainly to cholinergic and adrenergic transmitter actions, and it is postulated that three phases of the after-potentiation relate closely to the liberation of adrenergic transmitters from the different storage compartments.

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The physical and mental factors which concern the determination of the breaking point of breath holding and of rebreathing were investigated in normal human subjects.
The hyperbolic intensity-duration relationship of ventilatory stimulation of CO₂, which has been revealed about the breaking point of breath holding, applies also in the onset of diaphragm activity during breath holding.
The basic tolerable CO₂ level, which corresponds to the rheobase in electrical stimulation, was almost the same as, or a little lower than, the normal resting P_{A, CO2} level for the breaking point as well as for the onset of diaphragm activity, and showed few individual variations and training effects.
It is considered that in the intensity-duration relationship the basic tolerable CO₂ level dominantly related to the chemosensibility of the respiratory central structures, and the time factor may be in larger part related to mental or psychological events. The onset of diaphragm activity during breath holding is mainly attributed to physical factors.
The tolerance time of rebreathing with a restricted tidal volume and at a definite rate was longer than breath holding time, even when the tidal volume was as tightly restricted as to 0.11. Single deep rebreathing at the breaking point caused a great relief from distress and made several succssive breath holding possible.
In the successive breath holding, however, the period of absence of the rhythmic respiratory activity could hardly be observed.
These increasing effects of respiratory movement upon the tolerance time are not ascribed to changes in physical conditions, but probably relate to some unexplained neural mechanisms.

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1. An increase in transaminase activities in the serum and skeletal muscle from mice with hereditary muscular dystrophy was confirmed. Almost a two fold elevation of aspartate- and alanine-transaminase activities was observed in the serum of dystrophic mice. An increase of these two enzymes in the skeletal muscle was significant on a wet weight or total nitrogen basis.
2. Quantitative alterations in the transaminase enzymes of the dystrophic skeletal muscle were measured with regard to the isozyme compositions. Difference of thermostability in the enzymes of skeletal muscle homogenates between dystrophic and normal mice was also observed. No elevation of alanine-transaminase activity was observed in the dystrophic skeletal muscle following addition of a heat denatured serum, while a marked elevation was observed in the normal skeletal muscle.

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This experiment was undertaken to elucidate the concept that alterations of sex hormone and oxytocin in the systemic circulation exert remarkable influences upon the excitabilities of the multisynaptic pathways in the central nervous system. Observations were made on ovariectomized matured cats and rabbits with or without estrogen or progesterone treatment. The electrodes were permanently implanted into the brain and around the sciatic nerve and the dorsal root of the sacral segment, recording the evoked potentials in the hypothalamus, mesencephalic reticular formation (RF) and the medial lemniscus (ML) by electrical stimulation of the contralateral sciatic nerve, the dorsal root of the sacral segment, or by electrical stimulation of the hippocampus and amygdala. The results were as follows:
1. During estrus induced by estrogen-progesterone priming of ovariectomized animals, the evoked potentials in the periventricular arcuate nucleus (ARC) and the RF to which single shock stimuli were delivered from the sciatic nerve were facilitated as compared with those during anestrus, while those in the same regions by stimulation of the dorsal root of the sacral segment were inhibited. In the non-estrogen primed, ovariectomized animals, a subcutaneous in jection of progesterone (5mg) evoked the opposite response in the ARC and the RF from that during estrus. Sacral stimulation increased the potential while stimulation of the sciatic nerve inhibited the potential.
The hippocampally evoked potential in the ARC was inhibited in estrus, while facilitated after subcutaneous injection of progesterone (5mg). On the contrary, the amygdalarly evoked potential was facilitated during estrus, and inhibited after a subcutaneous injection of progesterone (5mg). On the basis of observations of the evoked potential and EEG pattern it was suggested that LH (0.3U.) had a facilitatory effect on the activity of the hippocampushypothalamus system and an inhibitory effect on that of the amygdala-hypothalamus system. The effect of FSH (100 I.U.) on these two systems was the complete reverse of the LH effect. Furthermore, it was noted that the RF responded to FSH independent of the hypothalamic response.
2. The sacrally evoked potential in the ARC was facilitated after an intravenous in jection of oxytocin (0.3-0.4 I.U.) during estrus, and this was inhibited during the period of highly concentrated progesterone in the blood; the sciatically evoked potential in this region was inhibited after oxytocin administration at estrus, and facilitated after subcutaneous injection of progesterone (5mg).
Many more facilitatory and inhibitory effects upon the evoked potential were observed in the RF than in the ML at the midbrain level by the peripheral afferent volley after intravenous injection of oxytocin, as well as during the period of anestrus and estrus.
The facilitatory or inhibitory effect of the evoked potential in the ARC elicited by the afferent volley was noticeably depressed after lesion of the RF, while a lesion of the ML exerted only a slightly depressing effect upon the evoked potential recorded in the same area of the ARC.
In short, it was observed that during estrogen dominance over progesterone, for example at estrus, the function of the RF was to facilitate transmission of somato-sensory afferent impulses to the higher center, and the inhibit viscerosensory afferent impulses. Conversely, if the influence of progesterone exceeded that of estrogen, for example during pregnancy, the activity of the RF was reversed; transmission of the peripheral somato-sensory afferent impulses to the higher center was inhibited while transmission of viscero-sensory afferent impulses was facilitated. When oxytocin increased in systemic circulation the evoked potentials are inverted in both circumstances.

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1. The glossopharyngeal nerve responses in rabbits and cats to taste and thermal stimulation of the posterior third of the tongue were recorded.
2. The nerve shows responses to water, 0.5 M NaCl, 0.5 M KCl, 0.02 M quinine hydrochloride, 0.005 N HCl and 0.5 M sucrose in rabbits, and in cats to 1 M NaCl, 1 M KCl, 0.02 M quinine and 0.01 N HCl but not to water and 0.5 M sucrose.
3. The response to taste stimulation of the circumvallate papilla in rabbits has a latency of several sec and shows a characteristic gradual time-course, but the response to taste stimulation of the foliate papillae in rabbits and that of the circumvallate papillae in cats attain a maximum rapidly.
4. In rabbits relative magnitudes of response to 0.02 M quinine, 0.005 N HCl, 0.5 M sucrose and 0.5 M KCl are greater than those in the chorda tympani, and in cats those for 0.02 M quinine and 0.01 N HCl are also greater than those in the chorda tympani.
5. The response to NaCl increases with an increase in NaCl concentration up to 4 M in both rabbits and cats.
6. The response in rabbits is mainly originated from the foliate papillae, and threshold for stimulation of the circumvallate papilla in this species is very high. The response in cats is mainly attributed to the circumvallate papillae because the foliate papillae in cats show little response.
7. The nerve responds well to both cooling and warming of the tongue in both animal species.

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Microsomal fractions (between 12, 400×g and 67, 500×g) were obtained from rabbit red (soleus, semitendinosus) and white (psoas) muscle. The relaxing activity, the ATPase activity and the calcium uptake of the microsomal fractions of these muscles were studied under various experimental conditions.
The following results were obtained.
1. The microsomal fraction of red muscle inhibited the mixed myofibrillar ATPase activity, i. e. relaxing activity was about 60% at the Q value 10, and it relaxed also the single glycerol-extracted muscle fiber prepared from rabbit psoas. The relaxation was reversed by addition of 20μM calcium and was spontaneously recovered by the further incubation.
2. The ATPase activity of red microsomal fraction was remarkably high and was inhibited about 50% on aging for one week at 0°C or by 5 to 20 mM azide, and it was not affected by 0.5 mM EGTA. This ATPase activity was not activated by addition of 20 to 200μM calcium. The effect of calcium on the ATPase was not shown, even when the ATPase of mitochondria presumably contaminating the red microsomal fraction was inhibited on aging or by azide.
3. The red microsomal fraction was able to accumulate calcium; the amount of calcium uptake was shown to be about 0.7μmoles/mg of protein/20 min at 200μM added calcium concentration. At 20μM added calcium concentration, more than 90% of the added calcium was removed from the reaction medium by the red microsomal fraction within 10 minutes.

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