294 AMYLASE IN NEWBORN
0 Spinco Division of Becknian Instrunients, Palo Alto, California.
activity for newborn infants is higher than for adults. Lower values by the UDPG consump-tion method can be explained by the substan-tial epimerase activity in newborn hemolysates
in the absence of exogenous NAD. As a
prac-tical matter, it is important that caution be
exercised in interpreting UDPG consumption
transferase values of newborns that fall within the range of galactosemia heterozygotes.
WON G. Nc, PH.D.
WILLIAM R. BERGHEN, PH.D.
GEORGE N. DONNELL, M.D.
J
OAN E. HODGMAN, M.D.Departments of Biochemistry and Pediatrics
School of Medicine
University of Southern California
and
Childrens Hospital of Los Angeles and
Los Angeles County General Hospital Address for Reprints:
(G.N.D.) Childrens Hospital of Los Angeles 4614 Sunset Boulevard
Los Angeles, California 90027
Appreciation is expressed to Sonja Wyss and Catalina Trevejo for technical assistance and to Malcolm Williamson for statistical analysis. Corn-puting assistance was obtained from the Health Sciences Computing Facility, U.C.L.A., sponsored by N.I.H. Grant FR-3.
This work was supported in part by grants from the United States Public Health Service AM-04135 and HD-00800.
REFERENCES
1. Kabacy, C., Hodgman,
J.,
Donnell, C. N., and Spears, R. L. : Galactose-l-phosphate uridyl transferase levels in the newborn. PEDIATRICS, 38:125, 1966.2. Bretthauer, R. K., Hansen, R. C., Donnell, C.
N., and Bergren, W. R. : A procedure for detecting carriers of galactosemia. Proc. Nat. Acad. Sci. U.S.A., 45:328, 1959.
3. Ng, W. C., Donnell, C. N., Hodgman,
J.
E., and Bergren, W. R. : Differences noted in uridine diphosphate galactose-4-epimerasebetween hemolysates of newborns and of
adults. Nature, in press.
4. Ng, W. C., Bergren, W. R., and Donnell, C. N.: Galactose-1-phosphate uridyltransferase as-say by use of radioactive galactose-1-phos-phate. Clin. Chim. Acta, 10:337, 1964.
5. Verachtert, H., Bass, S. T., Wilder,
J.,
andHansen, R. C. : Ion-exchange paper chroma-tography of nucleoside diphosphate sugars and related nucleotides. Anal. Biochem., 11: 497, 1965.
Serum
Amylase
Activity
in
the
Newborn
It is the prevailing opinion that amylase is
not detectable in the serum of normal newborn
infants.’ This often repeated view2’3 appears to
stem from evidence presented by Korowin4 in
1894 indicating that the pancreas of the
new-1)0111 was devoid of amylase. The techniques used for amylase determination in the past, how-ever, were relatively insensitive. In addition, the sizable volumes of serum required for quantita-tion did not lend these methods very well to the analysis of specimens obtainable from newborn infants. The recent availability of a highly sensi-tive saccharogenic technique for measuring
minute quantities of amylase’ prompted us,
therefore, to re-examine the matter of amylase
activity in the serum of neonates. Using an adaptation of this method6 that requires a total of only 20 .d of sample, we have been able to demonstrate amylase activity in serum samples obtained from infants soon after delivery.
MATERIALS AND METHODS
Capillary blood was obtained from the heels
of 68 normal infants at periods ranging from 1 to 72 hours following delivery. In eight
in-fants, similar specimens were secured on the first postnatal day and one or more times dur-ing the subsequent 48 hours. Blood was also
secured from mothers and the umbilical cords at nine normal deliveries.
Ten microliters of serum were incubated with 0.5 ml of buffered Lintner soluble starch for 1 hour at 37#{176}C.The serum-starch mixture was then treated with 1.0 ml of 3,5-dinitro-salicylic acid (DSNA) reagent. A blank was
prepared by mixing 0.5 ml of incubated starch
with another 10 nl of serum immediately
be-fore adding the DNSA reagent. The test and
blank mixtures were then placed in boiling
water for exactly 5 minutes and cooled in tap water for a 5-minute period. The optical density
of each solution was measured at 540 ms in
a Spinco Spectro-Colorimeter (model 151)#{176} against distilled water. After substracting the absorbance of the blank from the test solution, the net optical density was converted into
Somogyi units by means of a standard curve
prepared from dilutions of serum of assayed
* Expressed in ternis of 100 ml of serunl.
EXPERIENCE AND REASON-BRIEFLY RECORDED 295
RESULTS
Arnylase activity was noted in all of the 68 normal infants whose capillary blood was ex-anTlined within the first 72 hours after delivery. The values varied from as low as 6 to as high
as 63 Somogyi units over the time intervals studied (Table I). Application of the micro
method to samples collected from 69 appar-ently healthy adults yielded values ranging from 34 to 156 (average 83 ± 29) Somogyi
tIIlitS.#{176}
\Vhen categorized according to 24-hour
periods, the mean amylase activity noted on
the third day in the infants was slightly higher than that observed during the first day. The data, however, failed to demonstrate a clearly
changing pattern . Moreover, amylase activity
in the serum samples collected at repeated inter-vals from eight newborn infants during the
first 72 hours after delivery showed an increase
in three and a decrease in three, and it was
virtually unchanged in the remaining two
illfants.
The serum amylase level determined within the first 24 hours after birth in 18 of the
neonates whose mothers had been given
Demerol during labor averaged 26 ± 10
Somogyi units. By contrast, the mean level in the remaining 15 neonates whose mothers had
not received an opiate was 16 ± 7 Somogyi
ilIlits. The difference between these averages is
statistically significant (p < 0.01).
Maternal and umbilical cord blood samples collected at nine normal deliveries were an-alyzed for serum amylase activity (Table II).
Values obtained in the specimens from two
of the mothers exceeded the upper limit of
normal established with the method. Amylase activity in cord blood serum was low and bore no discernible relationship to that observed in
the mother’s serum. For example, cord
speci-TABLE I
AMYLASEMIA IN TIlE EARLY NEONATAL PEulon
Sern in A mylase Activity
TABLE II
(oII’AIIIsoN OF AMYLASE ACTIVITY IN MATERNAL
AND Coim BLOOD SERUM
(‘axe
.Vu mber
Serum 4 mylase Activity
(Somogyi Units*)
.l!aternal Cord Blood
1 2 3 4 5 6 7 8 9 172 91 70 135 62 72 103 49 225 23 3 5 24 23 28 16 2 5
mens three and nine both contained 5 Somogyi
units of amylase activity despite a three-fold
difference in serum amylase values of the
respective mothers.
COMMENT
The data herein presented indicate that,
contrary to existing opinion, relatively low levels of amylase activity may be demonstrated
in the serum of newborn infants or from cord
blood samples when determined by a sensitive
method adapted for use with small quantities
of serum.
The origins and characteristics of the starch-hydrolyzing activity demonstrable in the serum of the newborn infants remain to be elucidated and are beyond the scope of this report. It
may be of interest to note, however, that, in
one newborn baby whose pancreas we ex-amined, the amylase content was approximately
14 Somogyi units/gram. This degree of
activ-ity is almost 10,000 times smaller than the aver-age number of Somogyi units/gram we observed
in pancreatic tissue from six adults. It would seem unlikely, then, that the pancreas of the infant is a significant contributory source of
296 AMYLASE IN NEWBORN
than it was in 15 other neonates whose mothers had not received an opiate. Since the maternal
pancreas has vastly greater amylase activity
than does the newborn, the elevation of
amy-lase after opiate administration1 would seem
probably to have originated principally in the
mothers and been passed to the infants through the placenta.
SUMMARY
The presence of measurable quantities of
amylase in the serum of newborn infants or in
serum derived from cord blood may be demon-strated through the use of a sensitive
saccharo-genie procedure that permits analysis of small
quantities of serum. Serum amylase levels are
highly variable during the early part of the
neonatal period, but they usually tend to be
close to or below the lower limits of normal
established for adults. The origins of the serum amylase in the newborn infant remain to be elucidated.
RONALD L. SEARCY, PH.D.
Present Address: Research Division
Hoffmann-LaRoche, Inc.
Nutley, New Jersey 07110
J.
EDWARD BERK, M.D.Department of Medicine
SmNIcmRo HAYASHI, M.D. Department of Medicine BRUCE D. ACKERMAN, M.D. Department of Pediatrics
University of California
California College of Medicine and
Los Angeles County General Hospital
Unit 2
Los Angeles, California
This investigation was supported by a grant from the U.S. Public Health Service, Project GM
11897-03.
REFERENCES
1. Howell, R. R.: The diagnostic value of serum enzyme measurements.
J.
Pediat., 68:121, 1966.2. Somogyi, M. : Diastatic activity of human blood. Arch. Intern. Med., 67:665, 1941.
3. Janowitz, H. D., and Dreiling, D. A.: The plasma amylase: source, regulation and diag-nostic significance. Amer.
J.
Med., 27:924,1959.
4. Korowin: Ueber die fermentative Wirkung des pankreatischen Saftes und der Clandula parotis von Neugeborenen und Brustkindern auf St#{228}rke.Jahresb. Fortschr. Thier-Chem.,
3:159, 1894.
5. Ujihira, I., Searcy, R. L., Berk, J. E., and Hayashi, S. : A saccharogenic method for
estimating electrophoretic and chromato-graphic distribution of human serum amylase. Clin. Chem., 11:97, 1965.
6. Searcy, R. L., Hayashi, S., and Berk,
J.
E.: A new micro saccharogenic method for serum amylase determination. Amer.J.
Cliii. Path., 46:582, 1966.7. Berk,
