1. Spontaneous electrical activities in the guinea pig pulmonary bulbus were demonstrated in in vitro by a microelectrode, and the histological observation of this tissue was presented.
2. These spontaneous activities occurred independently of the right ventricular activity, and strictly localized within the bulbus.
3. The action potentials obtained from the middle portion of the bulbus were mostly of a pacemaker type with a plateau; while the majority of fibers in the distal and extremely proximal portions showed bizzare action potentials with low amplitude, low rate of depolarization, and a step or hump formation on the rising phase or the crest, as if they were recorded from the mammalian visceral smooth muscle or the atrio-ventricular node.
4. The origin of these electrical activities were ascribed to the cardiac fibers present in the adventitial side of the pulmonary bulbus (intra-bulbar myocardium) which were located dispersedly among the arterial smooth muscle and connective tissues.
5. It was speculated that the cardiac fibers located in these tissues changed their physiological property close to that of the smooth muscle. The functional roles of these activities were also discussed, but are not obvious at present.

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1. The reduction in the plasma K of K-deficient rats was in proportion to days of feeding of K-free diet, while no significant change was recognized in the plasma Na level.
2. A decrease in muscle K was not compensated by an equivalent increase in muscle Na during the first 5 weeks of K-deficiency, but the ratio of the number of Na ions entering the muscle to that of K ions coming out during further K-deficiency became approximately 1: 1. The net movement of ionic composition in SOLs was greater than that in EDLs.
3.[Na] i and [K] i in chronically and acutely denervated SOLs of K-deficient rats were modified close to a normal value as compared with innervated companions, but recovery of the ionic concentration by denervation was not found in denervated EDLs. Simultaneously, facilitation of the active movement of Na and K ions in denervated SOLs was observed in K-deficient rats which received 1.5mM/Kg. of K-salts for a week as well as 6mM/Kg. of Na-salt for 3 days after denervation.
4. The treatment of K-deficient rats with normal diet for a week as well as 6mM/Kg. of K-salts for 3 days resulted in marked restoration of the ionic composition in plasma and muscles, the active movement of Na and K ions in innervated muscles being greater than that in denervated ones. Furthermore, inhibition of the active transport was greater in denervated EDLs than in denervated SOLs.
5. Active K uptake was quantitatively greater than Na excretion in both kinds of SOLs and innervated EDLs when K-deficient rats received 1.5mM/ Kg. of K-salts for a week. On the other hand, the rate of recovery of K uptake to Na excretion of K-deficient rats which were fed a normal diet for a week or received 6mM/Kg. of K-salts for 3 days was 1: 1.
6. The wet weight of denervated muscles was smaller than that of innervated ones when both SOL and EDL muscles were weighed at the end of the experiments.

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1. Effect of chlorpromazine (CPZ) and imipramine (IMP) on the overt behavior was studied in fish, frogs, pigeons, mice, rats, and rabbits and also on the EEG and conditioned reflex activity in pigeons and rabbits.
2. In general, it can be said that IMP acts more strongly upon the nonneocorticate animals in their behavioral changes than the neocorticate ones, while for CPZ the reverse manner is true.
3. In pigeons the administration of CPZ alters, to some degree, the EEG pattern of slow, high-voltage wave, while that of IMP provokes EEG-desynchronization. In rabbits the administration of CPZ as well as IMP modifies the EEG pattern into slow, high-voltage wave. Observations on the duration of the effect on EEG changes show that CPZ is much stronger than IMP in mammals.
4. In pigeons the administration of CPZ does not disturb simple defensive conditioned reflex, but food motor conditioned reflex is impaired. Administration of IMP impairs more profoundly simple defensive conditioned reflex and food motor conditioned reflex than that of CPZ in pigeons. In rabbits food motor conditioned reflex is very slightly disturbed by low doses of IMP, only being disappeared by high doses of the drug, while low doses of CPZ are enough to cause the disappearance of food motor conditioned reflex.
5. Discussion is made by comparing the action of both drugs, from the point of view of phylogeny on the central nervous system, and suggests that although the action of IMP is complex, it acts primarily upon the function of correlation between the somatic and visceral components in the brain stem reticular formations and then the diffuse activating system; the effect of CPZ, on the other hand, is primarily on the activating system, the descending i nhibitory function and the neocortex, while affecting the function of correla-tion between the somatic and visceral components of the reticular formations.

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1. When a rhodopsin solution was exposed to a continuous illumination of dim green light, the element R was observed. On the other hand, when a rhodopsin solution was exposed to a flash of bright light, the immediate rise of pH was observed.
2. Both the element R and the immediate rise of pH were secondary reactions having scanty of physiological meaning.
3. It is likely that the primary reaction, induced on exposure of rhodopsin solution to light, is the photo-release of oxygen from rhodopsin molecules.
4. The volume of released oxygen on illumination may be calculated from the values of Δ[H⁺], as follows:
Ω_R=Δ[H⁺] _R/5·10⁶ [H⁺] +9·10¹⁵ [H⁺] ²,
and
Ω_I=Δ[H⁺] _I/5·10⁶ [H⁺] +9·10¹⁵ [H⁺] ².
where Ω_R is mole density of the oxygen molecules released from 10^-8 mol/ml rhodopsin on a 10-minute illumination of dim green light, and Ω_I is mole density of released oxygen molecules from 10^-8 mol/ml rhodopsin in 10 seconds on exposure to a flash of bright light.
5. Both the maximums of Ω_R and Ω_I were found at pH 6.60.
6. Process I, which was reported by R. HARA, may be the uptake of H ions by the oxygen atoms released from rhodopsin molecules on illumination.

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The activity of Na⁺, K⁺-activatied ATPase or transport ATPase (tATPase) was measured on a cell membrane fraction of the anterior pituitary of male rats. The enzyme activity increased either 2 weeks after thyroidectomy or one week after adrenalectomy. The increased activity was depressed 4 hours after injection of a small amount of T₄ (20μg per 100g body weight) or corticosterone (1 mg per 100g body weight), respectively. Similar depres depressive effects were observed with the enzyme preparation from intact animals. Physiologically occurring thyroid hormones, T₄, T₃ and TA₄, depressed the enzyme in vitro. Glucocorticoids, corticosterone, cortisol, cortisone and dexamethasone, were similarly effective in vitro. The effective concentrations of these hormones were as low as 10^-8M. In contrast, D-T₄, iodide, iodotyrosines, testosterone propionate, estradiol-17β and cholesterol were entirely ineffective. These results indicate that rat anterior pituitary tATPase is one of the target enzymes of the thyroid and adrenocortical hormones. The enzyme is directly and specifically depressed by these hormones.
These findings were discussed in relation to the mechanisms of the feedback regulation of anterior pituitary functions by the thyroid or adrenal cortex.

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Interactions between the slow negativity component of the photically evoked potential and the regular 5-7/sec wave of the spontaneous EEG were systematically investigated in rabbit's cortex with chronically and acutely implanted electrodes. The following interaction was seen:
1. As the evoked slow negativity developed, the relative amplitudes of the simultaneously elicited spontaneous regular waves, as related to the control, gradually decreased. When the apex of the regular wave was coincident with the peak of the slow negativity, the relative amplitudes of the spontaneous regular wave to the control was minimum, with maximum occlusion. At the end of the falling phase of the slow negativity, the regular wave was briefly facilitated.
2. As the regular wave ascended to the surface-negative phase, the relative amplitude of the slow negativity to the control decreased. At the apex of the regular wave, the occlusion became maximum, and then as the regular wave descended the occlusion weakened. The slow negativity elicited at the end of falling phase of the regular wave was briefly facilitated. This curve of excitability change was very similar with that of the regular wave in reference to the slow negativity.
3. The interaction between two slow negativities showed the same pattern of facilitation and occlusion in the excitability curve as that between the slow negativity and the spontaneous regular wave.
From the present findings it was concluded that the neural elements which contribute to the generation of the spontaneous regular EEG include those concerning the generation of the slow negativity of the evoked potential.

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1. The effects of abolition of the action potential on the tension development were investigated in the isolated frog ventricular muscle. A series of anodal pulses was applied at various time after the driving stimulus by using the separation chamber method.
2. Anodal pulses applied during an action potential markedly affected the tension development. Abolitions in the early phase of action potential produced strong inhibitory effects both on the rate of rise and time to peak of tension, while abolitions in the later phase caused less effects. According to the time point of abolition the coupling process between action potential and contraction followed at least four sequential phases.
3. The curve of maximum rate of tension development corresponding to each action potentials with different durations rose gradually and attained to its maximum 200 to 300 msec earlier than the peak of isometric tension. This curve, tentatively termed as the “activator-releasing” curve, was supposed to reflect the instantaneous amount of displaced activator calcium and determined to precede the development of active state.
4. The high calcium solution (5.6mM/l) augmented the degree of coupling in all sequential phases, while the low calcium solution (1.4mM/l) diminished it. 5. A distinct inflection was found between the phase 1 and phase 2 in the “activator-releasing” curve. This finding strongly suggests that there are at least two different sources for activator calcium in the frog ventricle.

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In rats it has been shown that after adrenalectomy the toxic hypothermic response to endotoxin became intensified and blood pressure tended to decline, without reduction in pulse pressures. Terminally dyspnea appeared and arterial pressure rose, but pulse pressures became much reduced. The course was terminated by respiratory arrest. This terminal phase was characterized by an enormous rise in the right ventricular systolic pressure. The autopsy finding showed characteristic blood stagnations indicating acute right heart failure, the lung not being affected. In contrast with the case of intact rats no hemorrhagic lesions of the gastro-intestinal tract were observed. The increased susceptibility to endotoxin after adrenalectomy was completely inhibited by pretreatment with glucocorticoids or endotoxin-conditioning. The course of shock could also be checked by intravenous glucocorticoid administration during the initial hypothermic and hypotensive phase, that is perhaps of central origin. The anti-endotoxic potency of glucocorticoid was found to be almost parallel with their anti-inflammatory potency. The terminal events appeared only in the presence of intact vagi and the possibility that this terminal event may be the result of the progressive central effect has been discussed. Discussions were also made on the mechanism of endotoxin tolerance, which might differ from species to species.

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The influence of electrical stimulation of the medulla oblongata and associated structure on gastric motility of anesthetized and non-anesthetized dogs was studied.
Increase in gastric motility was observed on stimulation of the dorsal nucleus of the vagus, the solitary tract and its nucleus and the dorsal region of the reticular formation.
Inhibition of gastric motility was obtained on stimulation of the solitary tract and its nucleus, the dorsal region of the reticular formation and the dorsal nucleus of the vagus.
The efferent pathways for excitatory effects from the medulla oblongata were not only the vagus nerves but also the splanchnic nerves. The efferent pathways for inhibitory effect were also the splanchnic nerves and the vagus. Diagram presented in FIG.7 illustrates the regulation center upon the excitatory and inhibitory centers for stomach motility and the efferent pathways from them to the stomach.

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The oxygenation velocity of the red blood cell was studied by means of a rapid flow method by varying the flow velocity through an observation tube with blood samples from five normal human subjects. The flow velocity was fixed at three different levels of 294, 147 and 74cm·sec^-1. The oxygenation velocity was measured over an SO₂ range from 0 to about 70% and the velocity was expressed by the velocity factor described by MOCHIZUKI.
The F_c value increased with the flow velocity linearly at a low velocity range, but at a higher velocity range the rate of its increment decreased gradually. From the experimental facts the following conclusion was derived: The O₂ diffusion into the red blood cell is resisted dominantly by a boundary layer having a transfer coefficient which is strongly affected by convection around the cell surface.

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