Assaying conditions of serum γ-glutamyl transpeptidase (γ-GTP, EC. 2. 3. 2. 2.) were studied using L-γ-glutamyl-4-nitroanilide as the substrate on the basis of the conditions recommended by the Scandinavian Society of Clincal Chemistry (S. S. C. C.). The optimum conditions obtained were different from that of the S. S. C. C. as follows; pH (7.6 to 8.1), MgCl₂ (10mM→none), and NaCl (none→100mM). The optimum pH was found to be between 7.9 and 8.3 (mean 8.1, at 37°) ; not only with Tris buffer but also with many other buffers. The concentrations of buffers used were all optimal at 100mM.
The apparent activation of γ-GTP activity by various inorgnic salts was also studied. The rate of activation with MgCl₂ was found to be only slight (about 102%), and those with NaCl and KCI were from 110 to 120%. Thi sactivating effect by manys alts could not be found by utilizing a soluble substrate, L-γ-glutamyl-3-carboxy-4-nitroallilide. This suggests that the activating phenomenon is caused by the alteration of substrate solubility by the salts.
A solution of γ-glutamyl-4-nitroanilide solubilized with HCI was unstable at room temperature, and the degradated products inhibited γ-GTP activity. The inhibition rate was 4 percent per hour at room temperature.

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A simple enzymatic method is described for determination of lipid compositions of human serum lipoprotein fractions separated by agarose gel eiectrophoresis. Human serum lipoproteins were separated by electrophoresis using a agarose gel with four sample troghs or four gelplates.
Thereafter, one of the plates was stained with Sudan Black B for WHO Typing of hyperlipoprotehemia, and the others were stained separately with commercially available enzymatic reagents for determination of serum triglyceride, total cholesterol and phospholipids, during a short time to recognize the position of lipoprotein fractions in the gels. And then, each lipoprotein fraction area was cut out of the gels and stainLd further in tubes which contained the enzymatic reagents. After staining, the distribution ratios of these three lipids to each lipoprotein fraction were separately calculated from the ratios of each fraction to the total fractions in the optical density with regards to each lipid. Then, the lipid compositions of each fraction were determined by multiplying of these distribution ratios with each lipid concentration in serum. This method is simple to perform without any special instrument, and requires only small amount of sample. it also has sufficient reproducibility, specificity and sensitivit.

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To determine the intracellular ion activities of potassium and chloride, the present study was aimed to make single-barreled potassium sensitive and chloride sensitive liquid ion exchanger microelectrodes (K⁺-microelectrode and Cl^--microelectrode, respectively), and to measure the intracellular K⁺ and Cl^- activities in the toad urinary bladder epithelial cells.
The single-barreled K⁺- and Cl^--microelectrodes were made by the modification of Walker's technique. A Pyrex capillary tube was pulled with a pipette puller so that the outer diameter of the tip was less than 1μm. The tip of the inner surface which was siliconized, was filled with a K⁺-sensitive or Cl^--sensitive liquid ion exchanger and the stem was filled with 0.5 M KCl.
The characteristics of K⁺- and Cl^--microelectrodes were examined. The sensitivity slope (sRT/zF 1n 10) and the standard potential of the K⁺-microelectrode was 59.04±0.03mV/10 fold of ionic activity and 22.20±0.69mV, respectively. The slope and the standard potential of the Cl^--microelectrode was -54.38±0.19 and -42.23±0.90, respectively. The selectivity constant of K⁺-microelectrode was 53.96±4.00 for K⁺/Na⁺ and 3.48±0.15 for K⁺/NH₄⁺. In addition, that of Cl^--mlcroelectrode was 8.00±0.15 for Cl^-/HCO₃^- and 63.59 ±1.20 for Cl^-/H₂PO₄^-.
The present authors attempted to determine the intracellular K⁺ and Cl^- activities in the toad urinary bladder epithelial cells.
Under basal conditions, the intracellular K⁺ and Cl^- activity was 41.2±0.5 and 49.9± 1.2mM, respectively.
It was suggested that K⁺ and Cl^--microelectrodes could be available for determination of the intracellular K⁺ and Cl^- activities in a clinical field.

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The normal range was calculated using multivariate laboratory data. Multivariate data of each sample were replaced in a single variable as Mahalanobis' distance (D), and truncation and iteration methods were adopted to D variable. Normal ranges were calculated using means and standard deviations obtained from the final truncation. The standard deviations calculated in each iteration must be corrected. This method is applicable to calculate the normal ranges or clinical reference values from patient data.

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Serum alkaline phosphatase levels in normal adolescents were studied in 247 males and 237 females subdivided by sex, age and blood type. lsoenzyme characteristics in some cases were also studied.
Alkaline phosphatase activity was measured by the kinetic method for sera from 10, 13, 16 and 19 years old men and women. No statisticallsyi gnificant influence of blood type on enzyme activity was observed in all cases. Alkaline phosphatase level at age 19 is essentially equal to that of adults and shows no significant difference between males and females. The activities in both sexes at age 10, 13 and 16 are in apparent higher level, and the difference in the activitiesb etween males and females are observed at these ages. From the study of isoenzyme characteristics, it is considered that the high level of alkaline phosphatase in the serum from adolescent males and females is due to the high bone phosphatase seen during growth.
The variations in those normal levels and isoenzyme characteristics are of clear importance in assessing data from individual adolescent patients, for example, in comparison to adolescent with obesty.

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The specific activity of hepatic UDP-N-acetyl-glucosamine 2'-epimerase (UDPGlcNAc 2'-epimerase) and the hepatic concentration of free N-acetylneuraminic acid (free NANA=CMP-NANA including NANA) were measured in rats subjected to streptozotocin induced mild diabetes and to adrenalectomy. In additionto observing the influence of these treatments on the basal enzyme specific activity and free-NANA pool size, the effects on their ability to respond to injury were also examined.
1. Streptozotocin induced mild diabetes caused no changes in the basal enzyme specific activity (activity per mg Protein per hour) nor in free-NANA concentration, but the ability of the enzyme to increase in response to inlury was somewhat inhibited compared to that of normal controls. 2. Adrenalectomy caused 31% increase in the basal enzyme specific activlty, but the response to injury was completely inhibited. Adrenalectomy had noeffect on the basal free-NANA concentration, but the increase observed in control animals after inlury was not seen. 3. The serum insulin level of normal rats averaged 25.7±5.4μU per ml serum. Adrenalectomized rats had an average level of 23.3±4.2μU per ml serum, equivalent to normal controls. Two hours after inlury serum insulin levels increased from their respective basal levels 2-2.5 times in all cases.

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This paper confirms the usefulness of electrochemical detector (ED) for liquid chromatography in determining picogram amounts of catecholamines in mouse and rat brain. The extraction procedure was based on modifications of Kissinger's method and of Anton and Sayre, in which catecholamines were adsorbed on aluminum oxide and eluted with perchloric acid. Thedetector operates down to the 0.2-0.4ng range. Norepinephrine (NE) Ievels were 431±18ng/g in mouse brain and 426±19ng/g in the rat. Dopamine (DM) levels were 1,088±66ng/g in mouse brain and 787±33ng/g in the rat. The authors have-fouad significant changes in DM levels in rat whole brain depending on the method of sacrifice. Levels of NE in the forebrain after electrolytic destruction of the locus coeruleus were significantly decreased (24.2%) from that of control.

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