Nonprostatlc Formalin-Reslstant
Acid Phosphatase in the
Tasmanian Devil
analysis
To the Editor:
Tasmanian devils (&zrcoa marsupial,
was subjected
to routine
clinical
biochemical
tests. It was found that the activityof
serum
acid phosphatase
was extraordinarily
high, containing up to 465
King-Armstrong
units (1 K.A. unit = 1
mg phenol/30
min/100
ml of serum). A
formalin-resistantphosphatase and a
nonformalin-resistantphosphatase were
Blood
from
philu.s harri8ii),
recognized. The formalin-resistant phosphatase is characteristic of male mammals and is considered to be prostatic in
origin, but as this fraction was also
present in female Sarcophilus it is incorrect to refer to a prostatic acid phosphatase in the Tasmanian
devil.
We found the greatest
acid phosphatase activity in the bone marrow
(20,000K.A. units/gof tissue) while the
reticuloendothelial
system usually
had
activitygreaterthan 1000 K.A. units per
g. Certain organs were found to have
unusually
great acid phosphatase
activity; for example, the trachea had 1,200
K.A. units/g.
The source and function of
the acidphosphatase isnot known. It has
the same mobility as do $1-proteinson
electrophoresis.Examination of the
serum
of representatives
of other mar-
supial families showed that their acid
phosphatase
activities
were
within
normal mammalian
limits, except for the
tiger cat, Dasyurops maculatus, a close
relative of Sarcophilu8, which had even
greater acifl phosphatase activities than
Sarcophilus.
Examinations of other biochemical
features of Australian marsupials showed
some differences from other mammals,
none as startling as that reported above.
References
1.
Parsons, R.S.,
Heddle,
R.W.L.,
Flux,
W.G., and Guiler,E.R., Studies on the
blood of the Tasmanian devil. Comp.
Biochem. Physiol. 32, 345 (1970).
2. Parsons, R.S., Atwood, J.,Guiler,E.R.,
and Heddle,
R.W.L.,
Comparative
and
enzymes.
Camp. Biochem.
209 (1971).
4. Parsons,
R.S.; Heddle,
R.W.L.,
and
Guiler,E.R.,The distribution
ofacidphosphatase in the Tasmanian devil,Sarcophilus harrisii (Marsupialia
Dasyuridae).
Camp. Biochem. Physiol. 39B, 219 (1971).
Physiol.
studies
39B,
R. S. PARSONS
173 MacQuarie St.
Hobart, Tasmania
Australia,
7000
E. R.
Department
University
P.O. Box
GUILER
of Zoology
of Tasmania
Hobart
Tasmania
Australia 7001
Practical Aspects of Automating an
Ammonia-Specific Electrode
To the Editor:
Specific species electrodes
offer certain
advantages
over many corresponding
colorimetric
procedures:
sensitivity,
specificity, working range, cost per analysis,
and freedom from interferences
caused
by sample color and turbidity.
The full
usefulness of these sensorshas not been
realized in the clinicallaboratory,
a
major reason being that automated
sampling and reagent-mixing systems
have not been modified for use with
specific species electrodes.
At leastone electrode,the ammoniaspecific electrode
(Orion Research
Inc.,
11 Blackstone St., Cambridge, Mass.
02139) can be combined quite satisfactorily with standard
automatic
sampling and reagent addition systems.
In addition to the ammonia electrode
with a flow-through cap, our system
consistsofa Model 701 digitalpH meter
(Orion Research),and an AutoAnalyzer
sampler,pump, and recorder(Technicon
Instruments Corp., Tarrytown,
N. Y.
10591).
Problems encountered in the early
stagesofthiswork includeddegradation
of the hydrophobic electrodemembrane,
slow baseline recovery, and a noisy base-
line. Deterioration of the membrane was
traced
to an excessive
amount
of wetting
on the blood of monotremes and marsupials-I.Haematology. Camp. Biochem.
agent added to the sample-diluting solution to promote good bubble patterns.
Physiol. 39B, 203 (1971).
This
3. Parsons, R.S., Guiler, E.R., and Heddle,
R.W.L., Comparative studieson the blood
of monotremes and marsupials-H.
Electrolyte,
organic
constituents,
proteins,
gas
problem was solved simply by
decreasingthe amount of wetting agent
to the minimum requiredfor even flowof
solutionsin the train.
Slow recovery of the baselineat am-
monia concentrations of less than 10
,mol/literwas alleviated
by using 10
Lmol/literof ammonium chlorideas the
sample
diluent.
Samples
appear
as
peaks on a flatbaseline, and rinse-out
time ismuch shorter by this technique.
Noise in the baseline was traced to
electrical
noisepick-up by the electrode.
A very fiat and stable baseline was
obtained by grounding the metal pins of
the flow-through electrode
cap to the
ground of the digitalreadout device.
The system is currently
being evaluated as a new approach
for the determination
of ammonia
in a variety
of
aqueous media, including
whole blood
and plasma.
Normal values for the plasma procedure range from about 35 to 70 ig of
NH3 per 100 ml, with sample results
from four patientswith expected elevationsranging from about 100 to 150 ,g of
NH3 per 100 ml. Average error for the
method islessthan 1%. More detailed
descriptionsof the procedures will be
presentedat a laterdate.
ROBERT
L.
COLEMAN
Thorndike Memorial Laboratory
nd and 4th Harvard Medical Services
Boston City Hospital
Boston,
Mass.
0118
The Problem of Chlorine
in Distilled Water
To the Editor:
In 1953 Collierand Stuart (1) reported
the presence of chlorine or chloramine
(positive test with o-tolidine) in distilled
water from laboratory
reflux stills. The
chlorinecould be completely removed by
passingthe distillate
through a “Crystalab Deeminizer” ion-exchanger.
After moving into the present building, we began
passing
the “house”distilled water through the Deeminizer,
but thisquickly became clogged by the
growth of microorganisms.
To prepare
high-qualitywater for enzyme studies,
we then setup a Corning Model AG-lB
still,supplied with tap water. The
distillate
had a low conductivity
of
about 2 mho/cm,
but it was high in
availablechlorine,as determined by a
photometric o-tolidinemethod (standardized
against
commercial
NaOC1
solution
that had been titrated
iodometrically). In one set of determinations
the availablechlorine(not chloride) was
0.70, 0.14, and 2.9 mg/liter (ppm) for
CLINICAL CHEMISTRY, Vol. 18, No. 8, 1972 867