BIOLOGICAL ITS
BEHAVIOR
OF
ACCUMULATION
K5MnO4: IN
NORMAL
AND
TISSUES
PATHOLOGICAL
BRAIN
J. E. Roda,A. H. Soloway,P. Bendaand W. H. Sweet Neurosurgical Research Laboratories, Massachusetts General Hospital, Boston, Massachusetts
The binding of 56Mn-permanganateto subcutane ously transplanted
ependymoblastoma
in C3H mice,
60 mg Diabutol and 2.5 mg Thorazine, the 14 ani
mals of Subgroups A, B and C were subjected to a
associated with low levels in normal brain, muscle laparotomy with ligation of the common biiary duct. and blood, has been the subject of recent reports A catheter was also placed in the urinary bladder. (1,2) . During one of these studies (2 ), it was ob served that this anion or its metabolic product was
The isotope was then administered, and a total col lection of both urine and bile was made for assay. The second group of ten rabbits was divided into
trapped largely in the pulmonary endothelium after intravenous administration. This prompted the con sideration that this selective accumulation was the
two equal parts. One part received the isotope in jection in the ear vein; the other was injected via
result not of an active uptake by the lung but in
the right
stead of a simple filter action by the capillaries
of
period with a solution of the isotope in 20 cc of
this
physiological saline. In the ten animals of this sec ond group, a freezing lesion was produced over the
hypothesis by determining the biological behavior
right parietal convexity either 5 or 24 hr before
the organ (3). The present
study was designed
to evaluate
of 56MnO4 after its injection by different parenteral routes. The accumulation of this anion has also been studied in rabbits with cerebral necrotic lesions and edematous areas peripheral to this zone. METHODS
As in the previous studies (1,2), the isotope we used was 56Mn (half-life, 2.59 hr) produced by ther mal-neutron activation of stable potassium perman ganate. Twenty-six albino rabbits weighing 1.5—2kg were used to assay the 56Mn distribution in tissues. The
animals were divided into two groups : one group of 16 was used to study isotope accumulation in normal tissues, and a second group of ten animals was used to investigate concentrations of this nu clide in cerebral lesions produced by freezing. The first group of 16 animals was divided into subgroups.
isotope
common
carotid
administration.
artery
over
The purpose
a 10-mm
of this lesion
was an attempt to simulate conditions existing in a neoplastic
brain.
The
lesion
was produced
by
extradural application for 1 mm of a cooled 250 gin lead probe tapering
to an end 5 mm in diameter.
The probe was cooled to —75°Cby a mixture of acetone and dry ice. The aqueous solution for administration
approximately
500
contained
@Ci56Mn/ml with a chemical
concentration of 0.92 mg KMnO4/ml. All animals were injected with 0.3 ,@Ci/gm. The two groups of animals were sacrificed by barbiturate overdose 1 hr,
2 hr and 4 hr after isotope administration.
Blood
samples were taken immediately before the animal's death; after autopsy, bile and tissue samples were removed,
weighed
and counted.
From
this data the
percent total dose per gram was calculated for all the key tissues, and tissue ratios were determined.
In Subgroup A, consisting of four animals, the ear
RESULTS AND DISCUSSION
vein was injected. In Subgroup B with six animals the isotope was administered via the portal vein. In
Table
1 summarizes
the tissue-concentration
data
Subgroup C the four animals were injected through a catheter placed in the abdominal aorta at the level of both renal arteries. Finally, in Subgroup D two
Of
animals was injected through a catheter in the right common carotid artery. Under light anesthesia with
For reprints contact: A. H. Soloway, Dept. of Medicinal Chemistry, College of Pharmacy, Northeastern University, Boston, Mass. 02115.
Volume 10, Number 5
56Mn
when
K56MnO4
was
injected
into
rabbits.
Received Aug. 15, 1968; original accepted Nov. 21, 1968.
205
RODA, SOLOWAY, BENDA AND SWEET
Stable, low-isotope tamed 2 hr after
concentrations administration
in blood were at regardless of the
differences
between
isotopic
concentrations
in lung,
liver and kidney depending on the particular route of administration. As Table 1 shows, the lung has the highest amount of radioactivity when the isotope is injected in the ear vein. The liver shows appre ciably greater levels than lung when the isotope is
route of injection. Another important observation was that large quantities of isotope are eliminated
rapidly through the biliary duct, and this excretion pathway is independent of the administration route. This fact undoubtedly accounts for the fast clearance of 56Mn from the bloodstream. These findings cor
administered
by the portal
vein,
and the kidney
is
higher than the two other organs when the animal
roborate those of Greenberg et al (4), who observed
is injected
that the amounts excreted through the bile 24 hr after
greater levels of activity in the lung of animals in
injection were between 75 and 90% of the total
jected through the carotid artery are very similar
administered
to those in animals injected directly in the ear vein and are easily understood anatomically. The low activity in the brain can be explained by the blood
dose. Even at 4 hr after injection
much as 42%
of the total dose appeared
as
in the bile.
The amount of isotope excreted in the urine was always negligible even after the administration of this nuclide in the renal artery.
Supporting the filter hypothesis are the striking
at the level of the renal
arteries.
The
brain barrier which inhibits the passage (into the
CNS) of this anion or products derived from it. As Table 2 also shows, the ratios between
the tissues
TORoute TABLE 1. AVERAGEPERCENT TOTAL DOSE/GRAM IN ANIMAL TISSUESIN ADMINISTRATION ROUTE OF 56MnO4—RELATION of fime after adminis. injection trationSocrflce BoneBrainBloodBileUrineEarvein22.6 (hr)LungLiver
Spleen
±
0.003Earvein42.8
0.3033 ±
±
0.02
±
0.0002Portolvein40.09
±
0.06.62 0.006 ±
0Renalartery20.15
±
0.0022.0 0.06 ± ± 0.0020.85 0.003 .06 ± ±
0Renalartery40.21 0.006Carotidartery44.3
0.0061
0.02
±
.5 ±
0.51
0.36 ±
0.006
0.0080.0070.002
0.09
0.37
±
0.60.65 0.008
0Portalvein20.22
KidneyMuscle
01 2 ±
±
±
±
±
0.02 ±
±0.0@
0.0080.004 0.05 ±
±
±
±
016.5
5.60.02
±
± 7.80.08
±
±
±
0.0090.007 0.00226.3 0.0060.008
0.003
[email protected]
0.03 ±
0.26 ±
0.0003
0.0100.0@ 0.0001
0.00080.006 0.00010.01 0.00017.34.40.008
0.27 ±
0.37 ±
0.01 ±
0.03 0.13 ± 0.008 0.08 ±
0.060.01 0.008 6.7 ± ± 0.0020.0060.001 3.0 ± ±
0
00.006 —
0.6
0.53 ±
00.003
±
±
0.02 ±
±
±
±
±
±
±
±
0.0060.0010.00010.01 0.00317.6 11.90.007 0.06
± ± ± 0.00020.004 0.00010.01031.2 0.02 ± ± ±
0.001
0.0070.007 0.00010.01 042.3
± 0.002
0.02 ± ± 0.00010.001 00.008
±
±
0.50.006 ±
±
4.80.01
±
0.0002——
TABLE 2. TISSUESRATIOS RELATEDTO ROUTE OF INJECTION SacrificeRoute of adminis
after injection
trationtime (hr)Lung-liverLung-kidneyLiver-lungLiver-kidneyKidney-lungKidney-liverEar vein23J37.220.282.020.130.46Ear vein44.307.560.231 350.130.56Portalvein20.150.846.455.461.180.18Portal vein40.0650.2422.25.404.1 10.18Renal artery20.170.0225.660.1244.607.88Renal artery40.200.0704.990.3414.282.87Carotid artery42.868.1
206
10.342.830.1
20.35
JOURNAL OF NUCLEAR MEDICINE
BIOLOGICALBEHAVIOROF K56MnO4
TABLE 3. PERCENT TOTAL
DOSE/GRAM
IN RABBIT BRAIN
AFTER COLD LESION
IN RIGHT PARIETAL CORTEX Time ofsacri TimeficeafterRoute of cold cortexParietalOccipitaltrationtion adminis.after injec lesionFrontal (hr)(hr)Right
lob.Parietal LeftRight
LeftRight
0.001
0.10 0.10 0.05 0.027
0.024
0.17
0.001 0.008
0.18 0.002 0.008 0.23 0.17
0.006
0.45
0.006
0.003
0.12
0.0006
0.020
0.002 0.001
0.002
—
0.001 0.0005 0.001
0.55 0.61
—
0.001
0.001
i.v. i.v. i.v. i.v. i.v.
1 1 1 4 4
5 5 5 24 24
0.076 0.045 0.004 0.002 0.74
r.c. r.c. r.c. r.c. r.c.
1 1 1 4 4
5 5 5 24 24
r.c.
4
r.c.
4
0.009
0.009 0.0006
LeftRight
0.009
0.042
0.008
0.007 0.001
0.011
0.009
0.012
0.029 0.092 0.051
0.001 0.002 0.008 0.007
0.001
0.054
0.021 0.21
0.002 0.51 0.0008 0.0007 0.002 0.002 0.001 0.003
Left
Muscle
Skull
Blood
0.05 0.02
0.07 0.03 0.02
0.063 0.005 0.001
0.006 0.006
0.014
0.002
0.024
0.0006
0.007 0.002
0.011 0.007
0.024
0.001
0.020
0.007 0.003 0.001 0.001
0.019 0.014 0.018 0.004 0.005 0.001 0.002 0.002 0.0005 0.15 0.014 0.0009 0.067 0.001 0.0005 0.0008 0.002 0.0009 0.001 0.001 0.004 0.003
0.01 0.008 0.01 0.01
0.006 0.006
0.07
0.06
0.02
0.01
0.01
0.004
0.007 0.002
0.01 0.02
0.006
0.02
0.01
i.v. = intravenous. r.c. =
right carotid artery.
vary according to the route of injection of 56Mn. Only those animals injected in the carotid artery had ratios
between
tissues
which
were
similar
to those
Because normal brain levels were invariably low regardless of the route of administration, it seemed pertinent to determine whether 56Mn would concen
injected in the ear vein. These results support the suggestion that the K56MnO4 becomes particulate,
trate in cerebral lesions and/or edematous areas peripheral to a lesion. For this purpose, ten rabbits
possibly forming Mn02 microparticles
were prepared bearing freezing lesions extending over the right parietal cortex. The animals were injected with the isotope either 5 or 24 hr after the cerebral lesion was produced. Five of the animals were injected over a period of
under in vivo
conditions and is removed from the bloodstream by organs such as lung, liver and kidney in a manner similar to that of a ifiter. Aside from this passive
uptake, an active transport phenomenon also appears to occur in the case of certain tissues. This is readily shown in the case of the liver and kidney since there is basically a high level of radioactivity in these tis sues which appears to be independent of the route of administration. These observations are in agreement
with those of Maynard and Cotzias (5) , who found that tissues that are rich in mitochondria,
such as
liver and kidney, have a large manganese uptake, suggesting that this element may be essential for mitochondrial function. From these data it must be concluded that 56Mn accumulates
readily in three important
organs—the
lung, liver and kidney—after the injection of radio active permanganate. other manganese
Consequently,
isotopes
this nuclide or
appear to offer the possi
10 mm via the right common carotid artery with the isotope
diluted
in 20 cc of physiological
saline.
The
other five animals were injected with the undiluted isotope
in the ear vein. The purpose
of the carotid
injection was to determine whether there was any difference in the uptake of the isotope by the lesion in relation to both the proximity of the injection site
and the concentration of the administered nuclide. The animals were sacrificed 1—4hr after the injec tion of the isotope, and symmetrical tions of the cerebral
hemispheres
anatomical
see
were removed
sur
gically, counted and examined histologically. As seen in Table 3, the right cerebral hemisphere containing the lesion usually has much larger amounts of iso tope than the left hemisphere. Also, generally speak
bility for determining focal pathology in these organs
ing, the animals that were injected through the
by scanning. The localized lesions might well behave as “coldspots― analogous to the behavior of non functional adenomas in the thyroid gland following
their right brain than those injected by the intra venous route. Finally, those animals that were in
the administration of 1311Also the rapid elimination of manganese by the bile points to its potential as a diagnostic tool for studying gallbladder physio pathology. Volume 10, Number 5
carotid
artery
had higher
isotopic
accumulation
jected with 56Mn 24 hr after the formation lesion had larger amounts
of the nuclide
in
of the
in this area
than those with a 5-hr old lesion. Table 4, which gives the ratios of frontal,
parietal
cortex,
parietal
207
RODA, SOLOWAY, BENDA AND SWEET
TABLE 4. RATIOS OF PERCENTTOTAL DOSE/GRAM OF RIGHT TO LEFT ANATOMICAL CEREBRALREGIONS FOLLOWING COLD LESIONS IN RIGHT PARIETAL CORTEX Route ofTime sacrifice afterTime after coldFrontalParietal cortexParietalOccipitaladministrationinjection (hr)lesion
i.v. i.v. iv. iv. i.v.
(hr)right-to-leftright-to-leftright-to-leftright-to-left
5 5 5 24 24 5 5
4 4
r.c.
r.c. 4 4 4 4
24 24
11.1 14.3
6.6 2.0 30.8 30.0 0j 13.3
50.0
10.5
5.2 1.2 12.0 14.5
27.0 21.2 75.0
0.8 0.5 40.0 0.4
11.5
1.0
115.0
550.0
7.3 13.5 21.0 420.0
170.0
305.0
567.0
4.8
0.5 1.0
1.1
2.2 3.0
0.2
5
r.c. r.c. r.c. r.c. r.c.
8.4
5.0
60.0 20.0
2.0
4j 2.0
150.0 0.6
i.v. = intravenous. r.c.
right carotid artery.
and occipital regions from right and left hemispheres,
lesions at levels that depend on the route of admin
readily shows the difference
istration. Consequently, radioactive permanganate
between
the two sides.
It was apparent that the larger isotope uptake in pathological brain resulted from its concentration in the necrotic area and that these areas were greater in animals with older lesions. Levels of 56Mn in edematous
tissue
of the right hemisphere
may
have
potential
as a scanning
agent
for these
organs. Moreover, its rapid elimination in the bile
may permit its use for determining pathology in the gallbladder.
were also
elevated. lliis edema was easily discernible because
ACKNOWLEDGMENTS
the high number of counts obtained from the tissue
The authors are indebted to K. Someda of the Neuro
correlated well with the histological picture charac teristic of an edematous
state. Generally,
this edema
surgical Research Laboratories at the Massachusetts Gen
eral Hospital for his suggestions and assistance in the production
of freezing
lesions
in the
CNS.
The
authors
surrounds the necrotic area extending deeply into the ventricular wail and to the frontal lobe but pene
also wish to thank Mrs. Janette R. Messer and her asso ciates for their invaluable assistance and Joseph Balcius of
trating only slightly into the occipital lobe. It was seen, however, that the extension and localization of the edema was not uniform or consistent from one
the Physics Department at this Hospital for preparing and standardizing the radioactive solutions used. The interest and encouragement of Sixto Obrador, Chief of Neuro
animal
is gratefully
to another,
and this accounts
for the varia
tions in Table 3. An exception to the results with other animals is seen in the last intravenous rab bit in Table 3. This animal was ill at the time of sacrifice with a large edematous reaction extend ing into both hemispheres. This resulted in an abnor mal increase in the radioactive
uptake of the frontal
and occipital lobes of the left hemisphere. From these results it can be concluded that the edematous tissue adjacent to the necrotic area is more accessible
surgical Service at Clinica de la Concepcion, Madrid, Spain, acknowledged.
This
work
was
supported
by
grants from the John A. Hartford Foundation, Inc., the U.S. Atomic Energy Commission (AT(30-l)-3267) and the U.S. Public Health Service (CA-07368 and NB-04512). REFERENCES 1. SOLOWAY, A. H., ARONOW, S., KAUFMAN, C., BALCIUS,
J. F., WHITMAN, B. ANDMESSER, J. R.: Penetrationof brain and brain tumor. VI. Radioactive scanning agents. I. Nuci. Med. 8:792, 1967. 2. RODA, J. E., SOLOWAY, A. H., BENDA, P. AND SWEET,
to 56Mn circulating in the plasma (possibly as Mn02
W. H. : Evaluation of permanganate and manganous ions
particles) than normal brain is. The necrotic zone itself is even more easily penetrated. These results suggest that radioactive permanganate may be a useful scanning agent for detecting brain lesions in
as scanning agents. Neurochirurgia. 11 :246, 1968. 3. BENDA, P. AND BROWNELL, G. L. : The fate of radio active emboli injected into the cerebral circulation. The brain as a filter. I. Neuropathol. Erp. Neurol. 193:386,
man.
1960. 4. GREENBERG, D. M., Copp, D. H. AND CUTHBERTSON,
E. M. : Studies in mineral metabolism with the aid of arti SUMMARY
Radioactive permanganate as 56Mnhas been found to concentrate in lung, liver, kidney and cerebral 208
ficial radioactive
isotopes.
I. Biol. Chem.
147:749,
1943.
5. MAYNARD, L. S. AND Coims, G. C. : The partition of manganese among organs and intracellular organdIes of the rat. I. Biol.
Chem.
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1955.
JOURNAL OF NUCLEAR MEDICINE
