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Diastase concentration in the blood and urine of normal and of diabetic rats
VOl~. 1 (I947)
BIOCHIMICA ET BIOPHYSICA ACTA
4I 5
D I A S T A S E C ON C E N T R A T I O N IN T H E BLOOD AND U R I N E OF NORMAL AND OF D I A B E T I C RATS by E. HECHT
Pharmacological Laboratory of the State University, Leiden (Netherlands)
I n t h e course of a s t u d y d e v o t e d to the r e l a t i o n existing b e t w e e n p a n c r e a s a n d b l o o d c l o t t i n g x, t h e d i a s t a s e c o n c e n t r a t i o n in the b l o o d a n d urine of n o r m a l r a t s a n d of r a t s in which d i a b e t e s h a d been p r o v o k e d b y m e a n s of alloxan, was i n v e s t i g a t e d in some detail. As t h e u n e x p e c t e d l y high c o n c e n t r a t i o n of the d i a s t a s e in r a t b l o o d l e d to a m o d i fication of t h e t e c h n i q u e u s e d for its e s t i m a t i o n , a n d also b e c a u s e in the l i t e r a t u r e w i d e l y d i v e r g i n g v a l u e s a r e given for t h e p r o p o r t i o n b e t w e e n the d i a s t a s e c o n c e n t r a t i o n in the b l o o d of d i a b e t i c a n d of n o r m a l i n d i v i d u a l s , i t s e e m e d w o r t h while to publish o u r e x p e r i e n c e in full. W e used for o u r e x p e r i m e n t s r a t s t h a t h a d r e c e i v e d on two consecutive d a y s a n oral gift of 3 m l of a 2 o % d e x t r o s e solution followed a f t e r 45 m i n u t e s b y a subc u t a n e o u s i n j e c t i o n of 0.3 m l of a solution of a l l o x a n in distilled w a t e r (75 m g a l l o x a n p e r m l ) . T h e t a b l e gives t h e d i a s t a s e c o n c e n t r a t i o n in the b l o o d of i o d i a b e t i c r a t s , m e a s u r e d b y t h e a m o u n t of " d e x t r o s e " in m g o b t a i n e d b y the h y d r o l y s i s of glycogen, the a m o u n t of urine d i s c h a r g e d in a p e r i o d of one d a y b y t h e a n i m a l s 4 - 8 , a n d of t h r e e d a y s b y t h e o t h e r ones, t h e a b s o l u t e v a l u e of the s u g a r p r e s e n t in t h e u r i n e a n d its c o n c e n t r a t i o n . T h e d i a s t a s e c o n c e n t r a t i o n in t h e b l o o d of 6 n o r m a l r a t s a n d in t h a t of one a n i m a l (n. i i ) in which t h e a l l o x a n i n j e c t i o n h a d failed to induce diabetes, serve for c o m p a r i s o n . F o r t h e e s t i m a t i o n of t h e d i a s t a s e c o n c e n t r a t i o n d a t e s were chosen t h a t fell r e s p e c t i v e l y 9, 16, 44 a n d 75 d a y s a f t e r t h e a l l o x a n injection. T h e e s t i m a t i o n of the diastase concentration in the blood was c a r r i e d o u t according to the principle of BALTZER ~ a n d t h e d i r e c t i o n s given b y DEKKER 3, b u t , because of the v e r y high c o n c e n t r a t i o n of the d i a s t a s e in r a t blood, in a s o m e w h a t modified way. Four wide test tubes received each I ml of a 0.9% NaC1 solution, I ml distilled water, o.i ml of a saturated NaF solution, and finally o.I ml blood. The latter was taken from the tail of a rat by means of a pipette. Two of the tubes served as controls, but to the two other ones 9 ml of a freshly prepared o. 3 % glycogen sol were added. All four were immediately afterwards placed in a waterbath at 380 C, in which they remained for two hours. After that the tubes were cooled in ice water. To the two control tubes now also 9 ml glycogen sol were added, and then they received all four x ml o.i n NaOH and 5 ml of a o.45 % solution of ZnSO,, and were heated for a few minutes in boiling water. In this way the proteins were precipitated, and the enzyme activity was brought to an end. In the two hours during which the tubes remained in the water bath the blood diastase had hydrolysed part of the glycogen ; the reducing substances that were formed in this way, were estimated at the conclusion of the experiment according to the method of HAGI~DORNand JENSEN4. To this end we did not use the total amount of the filtrate obtained from the I7.2 ml fluid in each tube, but only i ml, for that appeared to be sufficient. For the dextrose estimation according to HAG~-DORNand JENsE~ instead of potassium ferricyanide made alkaline by the aid of carbonate, the ferricyanide reagent recommended by FUJITA
References p. 4z8.
416
E. HECHT
VOL. 1 (1947)
and OKAMOTO5 WaS used. T h e l a t t e r consists of 1.65 g p o t a s s i u m ferricyanide, 174 g sec. potassium p h o s p h a t e and 11.2 g K O H dissolved in distilled water, a n d b r o u g h t to a volume of i liter; it is to be kept in a d a r k bottle. On t h i s reagent 5 ml is added to I ml of t h e filtrate mentioned above. T h e tubes r e m a i n for 15 m i n u t e s in boiling water, a n d are t h e n for as m a n y m i n u t e s cooled in cold water. (If t h e m i x t u r e loses its yellow colour w h e n it is boiled, t h i s m e a n s t h a t not enough oxydiser is present, a n d t h e n more p o t a s s i u m ferricyanide h a s to be added. T h i s is done in gifts of 2 ml, after which t h e m i x t u r e is once more to be boiled for 15 m i n u t e s . The t r e a t m e n t is to be repeated untill t h e yellow colour persists. In our estimations, however, in which b u t I ml filtrate was used, t h e original a m o u n t of oxydiser was always sufficient). After t h e m i x t u r e h a s been cooled, t h e r e m a i n i n g oxydiser is estimated. To t h i s end use is m a d e of a m i x t u r e of K J, ZnSO 4 a n d NaC1. T h i s is obtained b y m i x i n g equal a m o u n t s of #he following two solutions; solution I consists of 5 g K J a n d 25 g NaC1 dissolved in distilled w a t e r and brought to a volume of I liter; t h e precipitation of iodine is p r e v e n t e d by t h e addition of a drop of m e r c u r y and by keeping t h e solution in a d a r k bottle; solution II consists of io g Z n S O , . 7 H z O and 25 g NaC1 dissolved in distilled water and b r o u g h t to a volume of ioo ml. An a m o u n t of 7.5 ml of the m i x t u r e and 5 ml diluted HCI (i vol. concentrated HC1 diluted w i t h 5 vol. distilled water) are added to t h e c o n t e n t s of each tube, a n d after t h e fluids h a v e thoroughly b~en mixed, t h e m i x t u r e is t i t r a t e d w i t h o.oo 5 n t h i o s u l p h a t e . A m y l u m dissolved to a n a m o u n t of i % in a concentrated NaC1 solution serves as indicator. (If ferricyanide solution has been added to restore t h e surplus of oxydiser, /or every 2 ml t h a t h a v e been used 3 ml of t h e m i x t u r e of K J, ZnSO~ a n d NaC1 and 2 ml diluted HCI should be added). As I ml o.oo 5 n ferricyanide solution a n d t h e e q u i v a l e n t a m o u n t of t h i o s u l p h a t e solution (i.e. I ml of t h e o.oo5 n solution) correspond w i t h o.I74 m g dextrose, and as of t h e original 17.2 ml fluid in t h e tubes always b u t I ml was used for t h e estimation, t h e a m o u n t of " d e x t r o s e " in mg t h a t under t h e conditions of t h e e x p e r i m e n t would be formed from t h e glycogen by t h e a m o u n t of diastase present in ioo ml blood, m u s t be (B - - A) 17.2. i o o o . o . i 7 4 , B a n d A being t h e a m o u n t s of t h e o.oo5 n t h i o s u l p h a t e solution in ml required for t h e t i t r a t i o n of t h e m i x t u r e s w i t h o u t a n d w i t h glycogen hydrolysis (cf. DEKKERa), pp. 267 and I64). T h e values for B and A t h e m s e l v e s are t h e averages of e s t i m a t i o n s m a d e in duplo.
The estimation of the diastase concentration in the urine was carried out either with the ordinary method of WOHLGEMUTH8, in which use is made of the diastase index d45 ~5' or else with the more accurate technique described by HALLMANN~ The average amounts of "dextrose" found by substituting the values obtained for B and A in the formula (B-A) I7.Z. IOOO.o.174, which, as indicated above, serve as a measure for the diastase concentration in the blood, were for 6 normal rats 6783 me, for IO rats in which by means of alloxan diabetes had been induced 65o 9 mg, and for I rat in which the alloxan injections had failed to provoke diabetes 6753 mg. The amount of "dextrose" produced by the same volume of normal human blood, varies between I9O mg and 3IO mg (see Table I). The differences between the amounts of diastase found in the various groups of rats remain within the range of the probable error, and there is therefore, no matter how strongly the intensity of the sugar excretion varies, and no matter how short or how long the time that elapsed between the induction of the diabetic condition and the determination of the diastase concentration, no difference between the values found for the latter in the blood of normal and of diabetic rats. With regard to the diastase concentration in the urine of diabetic, alloxan-resistant and normal rats there is no difference either, provided that the dilution of the urine in the diabetic rats - - the latter are all suffering from polyuria - - is taken into account. To this end the amount of "dextrose" that serves as a measure for the diastase concentration is multiplied by the amount of urine that is discharged on the day of the estimation the products prove to be practically identical: the average values appeared to be fo normal rats (4 estimations) 386, for rats in which alloxan had failed to induce diabetes (IO estimations) 4o2, and for diabetic rats (27 estimations) 352. References p. 418.
DIASTASE IN BLOOD AND URINE
VOL. 1 (I947)
417
TABLE I Number of days Mg " d e x t r o s e " between alloxan obtained from injection and glycogen by diaAmount of ]PercenAmount of diastase stase present in urine in ml rage sugarsecreted estimation Ioo ml blood in I or 3 days of sugar i n l o r 3 d a y s Urine
Number of t e s t animals
FEHLING'S
solution + + +
3 days: 149 ,, 185 ,, 24o
3.6 4.0 4.7
3 days : 5.3 g ,, 7-4g ,, I1.3 g
44 44 44
62Ol
trace
I day: 1I ,, 54 ,, 41
7.9 9.1
i day: 4.3 g ,, 3.7g
75 75 75
6794 6463 6405 5896 6285
8.6 8.1 O
3 days: 9.0 g ! ,, 6.6 g ,, o g!
9 9 9
5777 784 ° 6763 6974 6974
73
9.3
244
10.5
3 days : 6.8 g ,, 25.6 g
16 I6
797 ° 6198 7329 7237
+ + (control) (control)
,,
6
3 days: lO 5 ,, 82 ,, 29 not determ.
13
+ + neg. (control) (control)
14 15 16 I7
+ + (control) (control)
3 days:
9 IO II I2
,,
not determ.
5662 5782
T h e a u t h o r w a n t s t o t h a n k P r o f . S. E . D E JONGH f o r t h e h o s p i t a l i t y is h i s l a b o r a t o r y .
SUMMARY x. The estimation of t h e diastase concentration in t h e blood of normal rats, rats in which diabetes had been induced by means of alloxan, and in a r a t t h a t proved to be resistant against alloxan, gave practically identical values. 2. Similar estimations of t h e diastase concentration in t h e urine also failed to reveal differences, at least when t h e dilution of the urine owing to t h e polyuria of t h e diabetic animals, is taken into account. 3. The high concentration of the diastase in t h e rat blood required some modification in t h e technique of t h e estimation, of which details are given, RI~SUM]~ 1. Les teneurs en diastase du sang de rats normaux, de rats rendus diab6tiques par l'alloxane, et d'un rat r~sistant ~ Faction de l'alloxane, sent pratiquement les mgmes. 2. La mgme observation s'applique A l'urine, ~ la condition de tenir compte de la dilution du liquide due ~ la polyurie des arfimaux diab6tiques. 3. La teneur 61ev6e en diastase du sang du rat, n6cessite une modification, d$crite ici, de la technique habituelle du dosage de cet enzyme. ZUSAMMENFASSUNG 1. Die Bestimmung des Diastasegehaltes im Blur normaler, nach Applikation yon Alloxan diabetischer R a t t e n und einer Ratte, die gegen Behandlung mit Alloxan resistent war ergab praktisch identische Werte. 2. Analoge Diastasebestimmungen im Urin zeigten ebenfalls keine Abweichungen, falls dabei die Verdfinnung des Urins durch die den diabetischen R a t t e n eigene Polyurie mitberficksichtigt wurde.
References p. 4z8.
418
E. HECHT
VOL. 1 (1947)
3. Der hohe Diastasegehalt des Rattenblutes erforderte eine Modifikation der Bestimmungsmethodik, woriiber Besonderheiten mitgeteilt werden. REFERENCES E. H•CltT, Acta meal. Stand., in press. F. BALTZXR, II. Mitt. Klin. Wschr. 14 (1935) 1395. a W . A. L. DEKKER, L e i d e n I94 o. a H . C. HAGEDORN AND B. N. JENSEN, Bioch. Zschr., 135 (1923) 46.
5 A. FUJITA AND K. OKAMOTO,Bioch. Z,chr., 225 (I93 o) 368. 8 WOHLGIgMUTI-I,see 3, P. 80. L. HALLMANN, L e i p z i g I941.
R e c e i v e d April 24th , 194 7
BIOCHIMICA ET BIOPHYSICA ACTA
4I 5
D I A S T A S E C ON C E N T R A T I O N IN T H E BLOOD AND U R I N E OF NORMAL AND OF D I A B E T I C RATS by E. HECHT
Pharmacological Laboratory of the State University, Leiden (Netherlands)
I n t h e course of a s t u d y d e v o t e d to the r e l a t i o n existing b e t w e e n p a n c r e a s a n d b l o o d c l o t t i n g x, t h e d i a s t a s e c o n c e n t r a t i o n in the b l o o d a n d urine of n o r m a l r a t s a n d of r a t s in which d i a b e t e s h a d been p r o v o k e d b y m e a n s of alloxan, was i n v e s t i g a t e d in some detail. As t h e u n e x p e c t e d l y high c o n c e n t r a t i o n of the d i a s t a s e in r a t b l o o d l e d to a m o d i fication of t h e t e c h n i q u e u s e d for its e s t i m a t i o n , a n d also b e c a u s e in the l i t e r a t u r e w i d e l y d i v e r g i n g v a l u e s a r e given for t h e p r o p o r t i o n b e t w e e n the d i a s t a s e c o n c e n t r a t i o n in the b l o o d of d i a b e t i c a n d of n o r m a l i n d i v i d u a l s , i t s e e m e d w o r t h while to publish o u r e x p e r i e n c e in full. W e used for o u r e x p e r i m e n t s r a t s t h a t h a d r e c e i v e d on two consecutive d a y s a n oral gift of 3 m l of a 2 o % d e x t r o s e solution followed a f t e r 45 m i n u t e s b y a subc u t a n e o u s i n j e c t i o n of 0.3 m l of a solution of a l l o x a n in distilled w a t e r (75 m g a l l o x a n p e r m l ) . T h e t a b l e gives t h e d i a s t a s e c o n c e n t r a t i o n in the b l o o d of i o d i a b e t i c r a t s , m e a s u r e d b y t h e a m o u n t of " d e x t r o s e " in m g o b t a i n e d b y the h y d r o l y s i s of glycogen, the a m o u n t of urine d i s c h a r g e d in a p e r i o d of one d a y b y t h e a n i m a l s 4 - 8 , a n d of t h r e e d a y s b y t h e o t h e r ones, t h e a b s o l u t e v a l u e of the s u g a r p r e s e n t in t h e u r i n e a n d its c o n c e n t r a t i o n . T h e d i a s t a s e c o n c e n t r a t i o n in t h e b l o o d of 6 n o r m a l r a t s a n d in t h a t of one a n i m a l (n. i i ) in which t h e a l l o x a n i n j e c t i o n h a d failed to induce diabetes, serve for c o m p a r i s o n . F o r t h e e s t i m a t i o n of t h e d i a s t a s e c o n c e n t r a t i o n d a t e s were chosen t h a t fell r e s p e c t i v e l y 9, 16, 44 a n d 75 d a y s a f t e r t h e a l l o x a n injection. T h e e s t i m a t i o n of the diastase concentration in the blood was c a r r i e d o u t according to the principle of BALTZER ~ a n d t h e d i r e c t i o n s given b y DEKKER 3, b u t , because of the v e r y high c o n c e n t r a t i o n of the d i a s t a s e in r a t blood, in a s o m e w h a t modified way. Four wide test tubes received each I ml of a 0.9% NaC1 solution, I ml distilled water, o.i ml of a saturated NaF solution, and finally o.I ml blood. The latter was taken from the tail of a rat by means of a pipette. Two of the tubes served as controls, but to the two other ones 9 ml of a freshly prepared o. 3 % glycogen sol were added. All four were immediately afterwards placed in a waterbath at 380 C, in which they remained for two hours. After that the tubes were cooled in ice water. To the two control tubes now also 9 ml glycogen sol were added, and then they received all four x ml o.i n NaOH and 5 ml of a o.45 % solution of ZnSO,, and were heated for a few minutes in boiling water. In this way the proteins were precipitated, and the enzyme activity was brought to an end. In the two hours during which the tubes remained in the water bath the blood diastase had hydrolysed part of the glycogen ; the reducing substances that were formed in this way, were estimated at the conclusion of the experiment according to the method of HAGI~DORNand JENSEN4. To this end we did not use the total amount of the filtrate obtained from the I7.2 ml fluid in each tube, but only i ml, for that appeared to be sufficient. For the dextrose estimation according to HAG~-DORNand JENsE~ instead of potassium ferricyanide made alkaline by the aid of carbonate, the ferricyanide reagent recommended by FUJITA
References p. 4z8.
416
E. HECHT
VOL. 1 (1947)
and OKAMOTO5 WaS used. T h e l a t t e r consists of 1.65 g p o t a s s i u m ferricyanide, 174 g sec. potassium p h o s p h a t e and 11.2 g K O H dissolved in distilled water, a n d b r o u g h t to a volume of i liter; it is to be kept in a d a r k bottle. On t h i s reagent 5 ml is added to I ml of t h e filtrate mentioned above. T h e tubes r e m a i n for 15 m i n u t e s in boiling water, a n d are t h e n for as m a n y m i n u t e s cooled in cold water. (If t h e m i x t u r e loses its yellow colour w h e n it is boiled, t h i s m e a n s t h a t not enough oxydiser is present, a n d t h e n more p o t a s s i u m ferricyanide h a s to be added. T h i s is done in gifts of 2 ml, after which t h e m i x t u r e is once more to be boiled for 15 m i n u t e s . The t r e a t m e n t is to be repeated untill t h e yellow colour persists. In our estimations, however, in which b u t I ml filtrate was used, t h e original a m o u n t of oxydiser was always sufficient). After t h e m i x t u r e h a s been cooled, t h e r e m a i n i n g oxydiser is estimated. To t h i s end use is m a d e of a m i x t u r e of K J, ZnSO 4 a n d NaC1. T h i s is obtained b y m i x i n g equal a m o u n t s of #he following two solutions; solution I consists of 5 g K J a n d 25 g NaC1 dissolved in distilled w a t e r and brought to a volume of I liter; t h e precipitation of iodine is p r e v e n t e d by t h e addition of a drop of m e r c u r y and by keeping t h e solution in a d a r k bottle; solution II consists of io g Z n S O , . 7 H z O and 25 g NaC1 dissolved in distilled water and b r o u g h t to a volume of ioo ml. An a m o u n t of 7.5 ml of the m i x t u r e and 5 ml diluted HCI (i vol. concentrated HC1 diluted w i t h 5 vol. distilled water) are added to t h e c o n t e n t s of each tube, a n d after t h e fluids h a v e thoroughly b~en mixed, t h e m i x t u r e is t i t r a t e d w i t h o.oo 5 n t h i o s u l p h a t e . A m y l u m dissolved to a n a m o u n t of i % in a concentrated NaC1 solution serves as indicator. (If ferricyanide solution has been added to restore t h e surplus of oxydiser, /or every 2 ml t h a t h a v e been used 3 ml of t h e m i x t u r e of K J, ZnSO~ a n d NaC1 and 2 ml diluted HCI should be added). As I ml o.oo 5 n ferricyanide solution a n d t h e e q u i v a l e n t a m o u n t of t h i o s u l p h a t e solution (i.e. I ml of t h e o.oo5 n solution) correspond w i t h o.I74 m g dextrose, and as of t h e original 17.2 ml fluid in t h e tubes always b u t I ml was used for t h e estimation, t h e a m o u n t of " d e x t r o s e " in mg t h a t under t h e conditions of t h e e x p e r i m e n t would be formed from t h e glycogen by t h e a m o u n t of diastase present in ioo ml blood, m u s t be (B - - A) 17.2. i o o o . o . i 7 4 , B a n d A being t h e a m o u n t s of t h e o.oo5 n t h i o s u l p h a t e solution in ml required for t h e t i t r a t i o n of t h e m i x t u r e s w i t h o u t a n d w i t h glycogen hydrolysis (cf. DEKKERa), pp. 267 and I64). T h e values for B and A t h e m s e l v e s are t h e averages of e s t i m a t i o n s m a d e in duplo.
The estimation of the diastase concentration in the urine was carried out either with the ordinary method of WOHLGEMUTH8, in which use is made of the diastase index d45 ~5' or else with the more accurate technique described by HALLMANN~ The average amounts of "dextrose" found by substituting the values obtained for B and A in the formula (B-A) I7.Z. IOOO.o.174, which, as indicated above, serve as a measure for the diastase concentration in the blood, were for 6 normal rats 6783 me, for IO rats in which by means of alloxan diabetes had been induced 65o 9 mg, and for I rat in which the alloxan injections had failed to provoke diabetes 6753 mg. The amount of "dextrose" produced by the same volume of normal human blood, varies between I9O mg and 3IO mg (see Table I). The differences between the amounts of diastase found in the various groups of rats remain within the range of the probable error, and there is therefore, no matter how strongly the intensity of the sugar excretion varies, and no matter how short or how long the time that elapsed between the induction of the diabetic condition and the determination of the diastase concentration, no difference between the values found for the latter in the blood of normal and of diabetic rats. With regard to the diastase concentration in the urine of diabetic, alloxan-resistant and normal rats there is no difference either, provided that the dilution of the urine in the diabetic rats - - the latter are all suffering from polyuria - - is taken into account. To this end the amount of "dextrose" that serves as a measure for the diastase concentration is multiplied by the amount of urine that is discharged on the day of the estimation the products prove to be practically identical: the average values appeared to be fo normal rats (4 estimations) 386, for rats in which alloxan had failed to induce diabetes (IO estimations) 4o2, and for diabetic rats (27 estimations) 352. References p. 418.
DIASTASE IN BLOOD AND URINE
VOL. 1 (I947)
417
TABLE I Number of days Mg " d e x t r o s e " between alloxan obtained from injection and glycogen by diaAmount of ]PercenAmount of diastase stase present in urine in ml rage sugarsecreted estimation Ioo ml blood in I or 3 days of sugar i n l o r 3 d a y s Urine
Number of t e s t animals
FEHLING'S
solution + + +
3 days: 149 ,, 185 ,, 24o
3.6 4.0 4.7
3 days : 5.3 g ,, 7-4g ,, I1.3 g
44 44 44
62Ol
trace
I day: 1I ,, 54 ,, 41
7.9 9.1
i day: 4.3 g ,, 3.7g
75 75 75
6794 6463 6405 5896 6285
8.6 8.1 O
3 days: 9.0 g ! ,, 6.6 g ,, o g!
9 9 9
5777 784 ° 6763 6974 6974
73
9.3
244
10.5
3 days : 6.8 g ,, 25.6 g
16 I6
797 ° 6198 7329 7237
+ + (control) (control)
,,
6
3 days: lO 5 ,, 82 ,, 29 not determ.
13
+ + neg. (control) (control)
14 15 16 I7
+ + (control) (control)
3 days:
9 IO II I2
,,
not determ.
5662 5782
T h e a u t h o r w a n t s t o t h a n k P r o f . S. E . D E JONGH f o r t h e h o s p i t a l i t y is h i s l a b o r a t o r y .
SUMMARY x. The estimation of t h e diastase concentration in t h e blood of normal rats, rats in which diabetes had been induced by means of alloxan, and in a r a t t h a t proved to be resistant against alloxan, gave practically identical values. 2. Similar estimations of t h e diastase concentration in t h e urine also failed to reveal differences, at least when t h e dilution of the urine owing to t h e polyuria of t h e diabetic animals, is taken into account. 3. The high concentration of the diastase in t h e rat blood required some modification in t h e technique of t h e estimation, of which details are given, RI~SUM]~ 1. Les teneurs en diastase du sang de rats normaux, de rats rendus diab6tiques par l'alloxane, et d'un rat r~sistant ~ Faction de l'alloxane, sent pratiquement les mgmes. 2. La mgme observation s'applique A l'urine, ~ la condition de tenir compte de la dilution du liquide due ~ la polyurie des arfimaux diab6tiques. 3. La teneur 61ev6e en diastase du sang du rat, n6cessite une modification, d$crite ici, de la technique habituelle du dosage de cet enzyme. ZUSAMMENFASSUNG 1. Die Bestimmung des Diastasegehaltes im Blur normaler, nach Applikation yon Alloxan diabetischer R a t t e n und einer Ratte, die gegen Behandlung mit Alloxan resistent war ergab praktisch identische Werte. 2. Analoge Diastasebestimmungen im Urin zeigten ebenfalls keine Abweichungen, falls dabei die Verdfinnung des Urins durch die den diabetischen R a t t e n eigene Polyurie mitberficksichtigt wurde.
References p. 4z8.
418
E. HECHT
VOL. 1 (1947)
3. Der hohe Diastasegehalt des Rattenblutes erforderte eine Modifikation der Bestimmungsmethodik, woriiber Besonderheiten mitgeteilt werden. REFERENCES E. H•CltT, Acta meal. Stand., in press. F. BALTZXR, II. Mitt. Klin. Wschr. 14 (1935) 1395. a W . A. L. DEKKER, L e i d e n I94 o. a H . C. HAGEDORN AND B. N. JENSEN, Bioch. Zschr., 135 (1923) 46.
5 A. FUJITA AND K. OKAMOTO,Bioch. Z,chr., 225 (I93 o) 368. 8 WOHLGIgMUTI-I,see 3, P. 80. L. HALLMANN, L e i p z i g I941.
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