A marked elevation in plasma triglycerides is observed when experimental animals are anesthetized with a pentobarbital sodium injection (Nembutal^[○!R]), a most widely used anesthetic in animal experiments. This is proven, however, to be a false rise due to the interference of propylene glycol present in the solvent of the injection with the plasma triglyceride determinations. One mole of propylene glycol produces one mole of formaldehyde by oxidation. The formaldehyde thus generated from propylene glycol mixes with those from glycerol moiety of plasma triglycerides, and gives an enhanced color reaction to all chromogenic reactions with formaldehyde. Since most of the chemical methods for plasma triglyceride determination is based on either one of these color reactions, we have to pay attention to a hypertriglyceridemia due to such influence as exerted by a solvent additive of propylene glycol upon the triglyceride measurements.

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The changes in myocardial copper were studied over a period of five days after producing myocardial necrosis in albino rats by subcutaneous injection of isoproterenol. Two different doses of isoproterenol (85 mg/kg & 42.5 mg/kg) were used to study the effect of variation in the extent of myocardial damage on the behaviour of myocardial copper. It was interesting to note that there was mainly an increase in myocardial copper with the lower dose of isoproterenol whereas there was mainly a fall in myocardial copper with the higher dose of isoproterenol. It has been hypothesized that this difference in behaviour of myocardial copper with respect to the different doses of isoproterenol is related to the extent of the myocardial tissue which escapes injury. Confirmation of myocardial necrosis was done by ECG, enzymes (SGOT, SGPT & LDH) and histology. Estimation of myocardial copper was done by atomic absorption spectrophotometry (Perkin Elmer 303).

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This study was undertaken to investigate the effects of graded coronary constriction on regional gas tensions of the myocardium. In 12 open chest dogs, tissue carbon dioxide (PtCO₂) and oxygen (PtO₂) tensions were measured simultaneously in outer and inner layers of the myocardium using a mass spectrometer. In normal condition, higher PtO₂ and lower PtCO₂ were observed in outer layer than in inner layer. With application of coronary constriction, increase in PtCO₂ and decrease in PtO₂ were observed in both layers of the myocardium, but the response to the ischemic stimuli by applying coronary constriction in inner layer was different from that in outer layer. Severe coronary constriction, more than 90% in its diameter, was necessary to produce significant changes in both gas tensions in both layers of the myocardium. Decrease in PtO₂ was found in the condition of less severe coronary constriction and to be greater in inner layer than in outer layer of the myocardium. In terms of the changes in PtCO₂, inner layer was also more susceptible to the ischemic stimuli than outer layer. The greater and earlier elevation of PtCO₂ in inner layer than in outer layer is regarded as one of the possible mechanisms of the reduction of myocardial contraction in the early stage of myocardial ischemia.

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The QRS wave of the spatial magnitude electrocardiogram (ECG) was investigated in 86 cases of the ventricular septal defect (VSD). The relation-ship between the amplitude and the time interval of QRS wave of the spatial magnitude ECG and the various hemodynamic parameters obtained by the right heart catheterization and the defect area ascertained during the operations were evaluated. Methods and Subjects: 1. Subjects. Mean age of the subjects was 11.2 ± 8.2, ranging from 3 months to 34 years old. Cardiac catheterization was performed in 65 cases (75.6%), and the diagnosis was ascertained in 56 cases (65.1%) by cardiac surgery. They were classified into the following 5 types by the location of the defect, namely supracristal (8 cases), infracristal (32 cases), subvalvular (7 cases), muscular (none) and multiple VSD (10 cases). At investigation of the measured values, they were classified into the following three groups by their age, namely group I (less than 2 years old, 7 cases), group II (from 2 to 13 years old, 48 cases) and group III (more than 14 years old, 31 cases). 2. Recording of the spatial magnitude ECG: Spatial magnitude ECG was recorded by means of the spatial magnitude electrocardiograph constructed by Mori et al., leading each scalar ECG of Frank system to squaring, adding and square root circuits in order. Following formula was computed automatically by this apparatus. spatial magnitude ECG = √(X²+Y²+z²) Recording was made by means of 4 channel heat writing oscillograph simultaneously with 3 scalar ECG of Frank lead. The recording speed was 100 mm/sec. Results and Summary: 1. Patterns of the QRS wave of the spatial magnitude ECG were classified into 4 types. Type A showed trianglar configuration. There was a notch or a slur in front of the main QRS wave in type B, and at the behind of the main QRS wave in type C. In type D, a notch or a slur was located in front and at the behind of the main QRS wave. Type C was further subdevided into type C₁ and C₂ The amplitude of the terminal notch (h₃) was higher than a half of that of the main wave (h₂) in the former and was lower in the latter. Type D was also classified into type D₁ and D₂ in similar way as in type C. Type A was observed in 7%, type B in 11.6%, type C₁ in 17.4%, type C₂ in 15.0% (totally 32.4% in type

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