The circulatory effect of cigarette smoking on cerebral hemodynamics, blood pressure and pulse rate were investigated in four normal young men and eight elderly patients with mild diseases, all habitual tobacco smokers (10-20 cigarettes daily). (1) Decrease in cerebral vascular resistance (dilatation of cerebral blood vessel) and increase in cerebral blood flow were observed in all subjects with the ordinary smoking. On the other hand, blood pressure and pulse rate did not change or slightly increased. (2) A conspicuous increase in cerebral hemodynamic, blood pressure and pulse rate were observed in the elderly subjects with rapid smoking. (3) It is suggested that the cerebral circulatory effect of tobacco smoking is mainly due to the direct effect of nicotine, since a significant correlation is not observed between cerebral hemodynamic and blood pressure with ordinary smoking.

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On a variety of 30 hypertensive patients and 3 controls, relationship between serum renin concentration, renal renin content, and juxtaglomerular apparatus (JGA) was studied. A highly significant correlation was found between serum renin concentration and renal renin content. The correlations between serum renin concentration and juxtaglomerular granulation index (JGI), and between renal renin content and JGI were also significant. The correlation coefficients, however, were significantly lower than that between serum renin and renal renin. Several factors including staining techniques may be related to this difference. From these results, it is concluded that renin levels are related to the changes in the JGA on a variety of hypertensive patients, although these relations are still problematic in a few cases.

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Parameters obtained with several procedures assessing cardiac function which are handy enough to be carried out almost routinely were studied on their correlativity to obvious changes in the clinical course and on the difference between following three groups healthy subjects, ischemic heart disease without signs of heart failure and overt ischemic heart failure. It was clearly shown that most of the non-failing ischemic subjects were in the status of the latent heart failure, the range of distribution of the parameters in the ischemic heart disease being between those in the healthy and ischemic heart failure. Among the procedures studied, the ear-piece dye-dilution method was the most useful in the sense that it reflected cardiac function as it was at the time of the examination, while some other indices such as P wave duration in ECG and Q-I interval were rather poor in variability in relation to the clinical course. Actually P wave duration remained unchanged often long after the complete disappearance of signs of heart failure.

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Spatial magnitude electrocardiogram is a record of spatial magnitudes of cardiac vectors which vary spatially as a function of time on a linear time scale. Spatial magnitude electrocardiograms were recorded in seventy normal men. QRS waves of normal spatial magnitude electrocardiograms were classified in five definite patterns. The configurations of spatial magnitude electrocardiograms were determined by the spatial configurations of QRS loops. The characteristics of normal spatial magnitude electrocardiograms were investigated quantitatively as well as qualitatively by introducing various parameters for measurements. Clinical usefulness of this new electrocardiographic approach was discussed.

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It has been well known that the kidney is a rich source of angiotensinases. On the other hand, an increased plasma angiotensinase activity in the patients with uremia has been reported. However, the mechanism responsible for this increased plasma angiotensinase activity is obscure. Therefore, the present study was attempted (1) to examine the several properties of renal angiotensinases in normal rats, and (2) to investigate whether the experimental injuries of rat kidney can induce a release of angiotensinase into renal venous blood. Materials and Methods: Male white Wistar rats weighing between 200 and 250 g were used in all the experiments. Experimental groups were as follows: 1) Normal control group 2) Mercuric chloride intoxication group 3) Unilateral ureteral ligation group 4) Bilateral ureteral ligation group 5) Acute unilateral renal arterial constriction group 6) Aminonucleoside-nephrosis group The determination of angiotensinase activity was carried out using biological methods, based on the principle of incubating a known concentration of asparagine¹-angiotensin (Hypertensin, Ciba) with the material under standardized conditions and then assaying for residual pressor activity. Angiotensinase activity of plasma was expressed as nanograms (ng)/ml of plasma/10 min and that of kidney as ng/mg of wet weight tissue/20 min, respectively. Results. 1. Kidney showed higher angiotensin-ase activity than small intestine, liver, lung, adrenals, plasma, brain and skeletal muscle. Red blood cell hemolysate showed the highest activity. 2. The angiotensinase activity of renal cortex Was greater than that of medulla. 3. The optimal pH of renal angiotensinase activity was observed at 7.4 before freezing and thawing. 4. The treatment of freezing and thawing resulted in a marked increase of the renal angiotensinase activity at pH 4.6 and, finally, it reached the level similar to that at pH 7.4.

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There have been many reports of studies done on the localization of the site of origin of ventricular extrasystoles by means of electrocardiograms or vectorcardiograms. However, in the previous reports which were based on clinical cases, the site of origin were merely assumed, and the results obtained by animal experiments were difficult to apply to humans because of the difference in the leads used, and the discrepancy of heart-torso relationship between humans and animals. Moreover, there have been no papers which investigated the possible sites of origin in more detail, such as a focus in the subepicardium or in the subendocardium within the same myocardial region. Methods: Langendorf perfusion was done. The perfused canine heart was situated and held in a desired position with a holder within a hollow elliptic cylinder made of acryl resin filled with a Tyrode solution. The ratio between the major and minor axes of the cylinder was almost the same as that in an average human thorax. The position of the perfused heart was kept carefully in relation of that of the human heart and thorax. From the silver wire electrodes through the wall of the cylinder, a set of 12 leads ECG, and a Frank lead VCG were recorded. The heart was driven at a rate of 60-70 per minute through a bipolar electrode placed in the area near the sinus node. Also the electrodes, to elicit a ventricular extrasystole, were fixed firmly in place at each locus of the myocardium. Within a 500-600 msec delay after the pacing, a stimulus with a strength of less than 2-4 times the resting threshold was given to each site of the ventricles to elicit a ventricular extrasystole. Ventricular extrasystoles were elicited at the following ten sites: subepicardium and subendocardium at the conus area of the right ventricle; subepicardium and subendocardium at the anterolateral aspect of the free wall of the right ventricle; subepicardium and subendocardium at the basilar area of the left ventricle ; and the right side and left side of the interventricular septum. Twenty-eight dogs were used for these experiments. Results: In the case of the stimulation of the basilar portion of the left ventricle, the direction of the major QRS deflection was upward in leads III, V_R, V₁, V₂, and V₃, and downward in leads I, V_L, V₅, and V₆. On the stimulation of the subepicardial focus, the QRS pattern showed a slow upward incline, and a delta wave pattern was recognized. On the other hand, on stimulation of the subendocardial focus, the initial portion of the QRS showed a sudden upward rise. In VCG the spatial maximal QRS vector pointed to the right, anterior, inferior.

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A new method of serial determination of cardiac output has been employed to evaluate the cardiac function. It is based on the indocyanine green dye-dilution method with sampling from the systemic artery after injection of the dye into the right atrium. The purpose of the present study is to verify the reliability and reproducibility of this method, and to investigate the influence of cardiac glycoside and adrenergic β-receptor blockade upon the cardiac and renal functions, and also to determine the hemodynamic effect of electrical conversion of atrial fibrillation to sinus rhythm in patients with operated mitral stenosis. Part I. The Basic Studies for the Determination of Cardiac Output by Indocyanine Green-Dilution Method Materials and Methods. Indocyanine green in doses of I to 1.5 mg was injected into the right atrium through a 7F Lehman catheter inserted into the antecubital vein. Blood was sampled from the brachial or femoral artery through an indwelling arterial needle employing a Gilford constant withdrawal pump (Model 105S) and a cuvette densitometer (Model 1031R). The dye dilution curve was recorded on an 8-channel photographic recorder (Sanborn 4568A) with an electrocardiogram. The dye concentrations were replotted on a semilogarithmic paper. The curve was calibrated by whole blood and integrated sampling methods. The cardiac output was calculated according to Hamilton's formula. Two successive determinations of cardial indicies within 3 to 5 minutes were made in a total of 31 cases with or without heart disease. Results and Discussion: Fick and dye determination of cardiac output were carried out in 16 subjects. The average dye cardiac index was 2.74 ± 0.20 L/min/m² and the Fick was 2.94 ± 0.23 L/min/m². The correlation coefficient for Fick to dye was 0.88 (P <0.001). There was no significant difference between the mean values of these two groups. These results showed reliability of the dye method. The average cardiac index in the first determination of the two successive measurements within 3 to 5 minutes in 31 subjects was 2.86 ± 0.15 L/min/m². The average in the second determination was 2.88 ± 0.16 L/min/m². The percent difference between two successive determinations ranged from -13.3 to ± 10.5%. About 94% of all determinations were within ± 10% of the line of identity. The correlation coefficient was 0.99 (P <0.001). These results revealed good reproducibility of the dye-dilution method. The differences may be mainly due to the physiological changes rather than technical errors.

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