A new enzymatic method is proposed for the determinatin of triglyceride in serum.
The principle of this method is as follows: Triglyceride is hydrolyzed into glycerol and free fatty acid by lipopr teinlipase (Psedomonas fluorescens) ycerol is transformed to pyruvate in the presence of glycerokinase, pyruvatekinase, ATP and.phosphoenol pyruvate.Being rea: ted with hydrazine, pyruvate forms hydrazone which shows the maximum absorbance at 450nm under the basic condition.
The amount of triglyceride is calculated following a certain formula from the value of optical density obtained at 450nm.
The values of serum triglyceride determined by the proposed method were well correlated with those by the chemical method and enzymatic (Boehringer UV) method after chemical saponification.The precision of the method was also satisfactory.
Since the enzymatic method is simple and specific for the measurment of triglyceride in comparison with the chemical method, the former is suitable for estimating triglyceride in a clinical laboratoy.

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The lectrophtoercehtniiwcqi uteah s implteh ilna yepro lyacrylgaemlpir doevided a good resolution of serum amylase isozymes, with up to 9 being observed.From ther esulotfst hee lectrophomreobticl isttyu dieofss erum, pancreataincd salivaarmyy lase isozymes, we considered that the amylase isozymes in human serum were amixture of pancreatic and salivary amylase. In patients with acute pancreatitis, the activities of the amylase isozymes of pancreatic origin were increased.On the contrary, in patients with pancreatectomy, these isozymes disappeared. In patients with mumpus, the activities of amylase isozymes of salivary origin were increased.Only these amylase isozymes of salivary origin were observed in patients with pancreatectomy. From these observations, it is clear that amylase isozymes in human serum were of pancreatic and salivary origin.In normal sublects, 2 major bands of amylase isozymes and 2 to 4 minor bands were observed. All these amylase isozymes showed the same electrophoretic mobility as pancreatic or salivary amylase isozymes.

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Some problems of enzymatic assay of insulin degrading enzyme extracted from pig skeletal muscle were described.
Enzymatic assay of various kinds of insulin degrading enzyme has been generally carried out by determinig the131I-labeled degradation product of ¹³¹I-insuliinn trichloroacetic acid soluble supernatant (TCA method).As determined by this method, degradation appeared to level off when approximately 60% of the ¹³¹I-insulihna d been degraded, and so the enzyme activity appeared to be considerably lower than it was. This seemed to be due to the fact that a portion of the TCA soluble degradation products was carried down with the protein which was precipitated in the incubation mixtures by TCA.However, the relative rate and extent of degradation under various conditions was reliably determined with good reproducibility and simplicity by this method.
On the other hand, non-degraded insulin was assayed by double antibody radioimmunoassay after terminating the enzyme reaction by N-ethylmaleimide (RIA method). As determined by this RIA method, the degradation of insulin appeared to proceed more rapidly to completion, and so the enzyme activity proved to have been able to be determined more correctly than TCA method.
In conclusion, it seems that there is no perfect method of enzymatic assay of insulin degrading enzyme, though both TCA method and also RIA method have their advantages and disadvantages.Therefore, either, TCA method or RIA method should be selected as the experimental design.

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Rat kidney homogenate incubated with trypsin reduced the activity of β-glucuronidase. Since the incubated trypsin-solution without the homogenate showed no influence on the activity of β-glucuronidase, it was concuded that a certain inhibitor of the enzyme was turned out in rat kid ey tissue by trypsin treatment. A cortex fraction proved to be more effective than a medulla fraction, and among celluler components, a soluble fractioh was most potent.Furthermore, an addition of sodium sulfate not only abolished the inhibitory effect caused by the trypsin treatment but also activated β-glucuronidase to a certain level.This fact suggests that sodium sulfate is not a mere activator, but an agent having an ability to release the inhibitors from β-glucuronidase.

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