Pulmonary hemodynamics and respiratory functions have been investigated in various body positions. In these studies, however. especially of pulmonary hemodynamics some difficulties were encountered which came from the problem of the setting of reference zero point to measure the pressure common to variable body positions. The changes of pulmonary artery pressures refered to a settled zeropoint which were measured for ten minutes after tilting of the body head up at an angle of 45 degrees from the horizontal, were found to be not in-variable in different diseases and clearly showed different response patterns between stenosis or stenosis predominant and insufficiency or insufficiency predominant mitral valvular diseases. The pulmonary artery pressure response to 45 degree tilting is presented as a new, useful, differential diagnostic method for mitral valvular diseases, and for the determination of indication for cardiac surgery.

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The coronary inflow was measured with the cannulation method and the blood pressure was recorded by means of an Hg-manometer in anesthetized dogs placed on artificial respiration. The effects of the intracoronary and intravenous injections of veratrum alkaloids, nucleic acid derivatives, cardiac glycosides, autonomic drugs, histamine, posterior pituitary extract, inorganic salts, and metabolic inhibitors on the coronary blood flow, the heart rate, the blood pressure and the cardiac movment were observed in intact and vagosympathectomized dogs, and in dogs pretreated with autonomic blocking agents, as well as in the heart-lung preparation. From these results, the relation of the cardiac reflex eliciting action of drugs to the chemical structures, the cardiac actions, the effects on the coronary vessel, and the cardiac metabolism were discussed.

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1) In generalized phlebohypertension "true lymph flow" in the unopened, intact thoracic duct is much less, than that obtained from the transsected and cannulated duct. 2) Congestive heart failure is among other, well known causes precipitated by the "haemodynamic insufficiency" of the lymph system. 3) Chronic increase of superior vena pressure may lead to clot formation in the thoracic duct and other large lymph trunks, thus totally blocking lymph flow. By calling attention to this fact an until now unrecognised cause of resistance to therapy in cases of congestive heart failuse has been described. 4) Elevation of inferior vena cava pressure was in spite of previous bilateral nephrectomy accompanied in contrast to the finding of Katz and Cockett by an increased thoracic duct lymph flow. 5) The theory of Katz and Cockett, according to which Sodium retention in congestive heart failure can be explained by lymphatic back transport of Sodium into the blood stream instead of beeing excreted into the urine has been invalidated. 6) The mechanism outlined by Katz and Cockett may play an important role in various pathologic conditions characterised by isolated renal venous and/or inferior vena cava phlebohypertension.

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Automaticity of atrial muscle of the toad in modified Ringer's solution containing BaCl₂ and fibrillation of ventricular muscle of the frog in hypertonic Ringer's solution are studied by microscopical observations and records of intracellular action potential. The atrial muscle which has no automaticity in normal solution begins to contract rhythmically when BaCl₂ is added to it. In the region where excitation starts, pace-maker potential with slowly increasing depolarisation is observed. The pace-maker region is almost localized and occurrence of the excitation is rhythmical. Formation of pace-maker cell under such condition suggests a possibility of ectopic automaticity and myogenecity of excitation. In the hypertonic solution with two times excess NaCl, the ventricular muscle also con-tracts rhythmically. But microscopically there appears some quiecent fibers immediately adjoining to contracting fibers, the formers of which are also electrically silent. Namely, separation of unit in. movement is observed. Transition in shape of the intracellular action potential after replacing with the hypertonic solution may be divided into following three periods, that is, the first period when the spike-component disappears and duration of the action potential shortens, the second period when the plateau phase diminishes and a triangular wave remains, and the third period when this triangular wave reduces and finally disappears. From these observations, composition of the action potential may be divided into spikecomponent, plateau-component and slow potential component. This slow potential may be considered to correspond to inter-cellular myo-mvo-junction potential of visceral smooth muscle in normal solution and to peculiar slow potential of striated muscle in Ca⁺⁺-deficient solution. Basing on these facts mentioned, fibrillation of cardiac muscle is thought to start from ectopic focus of cxcitation and through variable multiple pathway of disturbed inter-cellular connections.

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There is a considerable discrepancy of opinions among different investigators as to the action of the autonomic nervous system on pulmonary blood vessels. In attempt to shed some light on this field and contribute to a fuller clinical understanding of the nature of this vascular bed, the author studied the effect of various drugs and of the electrical stimulation of the autonomic nerves on the pulmonary hemodynamics in cats with such experimental arrangements where as much as possible of the extrapulmonary factors likely to affect the pulmonary blood vessels was eliminated; the author discusses the autonomic nervous control of pulmonary blood vessels. Method s The chest of the cat was opened on the right side under a positive pressure respiration; according to the method of Burton various drugs, e. g., adrenaline, imidaline, acetylcholine and atropine, was injected directly into the pulmonary blood vessel individually or in combination ; the author severed the right cervical vagus nerve and right sympathetic trunk just beneath and above the inferior cervical ganglion and applied the electrical stimulation to the peripheral cut ends using 5-8 volts and 20 c.p.s.; changes produced by such procedures in the pulmonary blood flow were calculated. Results With adrenaline solution of 1 : 500, 000 dilution, imidalin or acetylcholine injected into the blood vessel of the lungs, or with the electrical stimulation of the vagus nerve, the pulmonary blood flow was increased. With adrenaline solution of 1 : 10, 000 dilution injected by the same way or immediately after the section of the vagus nerve, the pulmonary blood flow was decreased. With adrenaline solution of 1 : 100, 000 dilution or atropine solution injected, or with the unilateral electrical stimulation of the inferior cervical sympathetic trunk, no marked change resulted. During the phase of decreased flow produced by the injection of adrenaline solution of 1 : 10, 000 dilution, injection of acetylcholine caused the flow to be increased somewhat but still up to a level lower than in the control phase. With adrenaline solution of 1 : 10, 000 dilution injected after atropin, there occurred no decrease in flow. With adrenaline injected in 1 : 10, 000 dilution following an injection of imidaline, there occurred a slight decrease in flow.

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Malvin and others developed a new method to visualize the localization of tubular reabsorption of various substances by relatively simple stop flow technique. In this paper the author presents studies on the effects of various corticosteroids on tubular transport of electrolytes and its localization by this technique. Materials and method Dogs weighing 15-10kg were divided in 6 groups. 1) Control group received intravenous drip of glucose saline for the osmotic diuresis as indicated in Malvin's technique. Drugs to be tested were dissolved in the glucose saline above cited and injected intravenously. Their doses were as following. 2) Desoxycorticosterone glucoside 1 mg/kg. 3) Hydrocortisone hemisuccinate 10mg/kg, 4) Dexamethasone phosphate 0.8mg/kg and 0.4mg/kg. 5) Single intravenous injection of 20 IU ACTH and successive injection of ACTH for 4 days (20 IU i. m., 10 IU i. m., 10 IU i. m., 20 IU i. v.) 6) Hydrochlorothiazide 10mg/kg. Na and K were determined by flame photometer, Cl by Schales & Schales, PAH by Tsuda's method, Cratinine by Jaffe's method. From each samle of all urine collections, U/P/(U/Pcr) was calculated, where U/P is the concentration ratio of urine and plasma with the tested substance and U/Pcr is that with creatinine. To illustrate the localization of the tubular reabsorption U/P/(U/Pcr) was plotted to percent volume within kidney from left (distal) to right (proximal). Results a) The patterns of control group were very similar as Pitts and others published previously. (Table I, Fig. 1) b) Hydrochlorothiazide inhibited markedly the reabsorption of Na and Cl in distal tubuli. Increased secretion of K was observed also in distal tubuli. (Table I, Fig. 2) c) D O C increased Na and Cl reabsorption in distal and proximal tubuli. Peak of K in distal tubuli was not significant. (Table I, Fig. 3)

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Various investigations have been per- formed about the pathogenesis of atherosclerosis, and the view has recently become dominant that the disease is caused by disturbance of lipid metabolism. The author studied the serum lipid values of normal subjects of various ages and then of subjects with coronary diseases, diabetes, cerebrovascular diseases and hypertension. Each of the individuals was tested, as far as possible for all the items, cholesterol, lipoprotein index, free fatty acid, total fatty acid, neutral fat and phospholipid, and an attempt was made to determine which of them might serve as the best pointers of atherosclerosis. Experimental Methods The subjects consisted of 106 normotensive persons those whose blood pressure was consistently below 140/90 mmHg by repeated measurement--32 cases of diabetes mellitus. 22 of angina pectoris, 30 of myocardial infarction, 30 of cerebrovascular lesions and 101 of hypertension. The measurement of serum lipid fractions was carried out by the methods show below. 1) Cholesterol : Costello's method. 2) Lipoprotein index : paper electrophoresis. 3) Total fatty acid : extraction by Bloor and Katsura-Hatakeyama's method and measurement by alkali titration. S) Neutral fat : extraction by the same method and measurement by Bragdon's method. 6) Phospholipid : modified Zilversmit's method. Results 1) Serum lipid levels of normotensive subjects. In normotensive subjects under 50 years, the serum total cholesterol level was 167±35 mg/dl, free cholesterol level 52±15 mg/dl, average lipoprotein index 2.9±1.2, nonesterified fatty acid 0.25±0.12 mEq/l, serum total fatty acid level 268± mEq/l, serum neutral fat level 187±50 mg/dl, serum phospholipid level 155±36 mg/dl, and serum CIP ratio 0.97±0.26 ; and those levels above 50 years 185±40 mg/dl (total cholesterol), 59±15 mg/dl (free cholesterol), 3.5±1.9 (lipoprotein index), 0.32±0.10 mEq/l (nonesterified fatty acid), 376±85 mg/dl (total fatty acid). 224±80 mg/dl (neutral fat), 186±81 mg/dl (phospholipid), 1.13±0.35 (C/P ratio). Between the two age groups of normotensive subjects there is statistically significant difference in the total cholesterol, free cholesterol and phospholipid. The lipoprotein index, phospholipid, neutral fat, free fatty acid and total fatty acid have a tendency to increase with age. But there were two or three of the serum lipid fractions which showed a tendency of decreasing after 70 years of age.

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