Uracil incorporation in liver RNA of young and pregnant rats and in RNA of fetal tissues and certain tumors

Vol. 4, No.

2,196l

BIOCHEMICAL

AND

BIOPHYSICAL

RESEARCH

COMMUNICATIONS

URACIL INCORPORATION IN LIVER RNA OF YOUNG AND PREGNANT RATS AND IN RNA OF FETAL TISSUES AND CERTAIN TUMORS+ A.Cantarow, Departments Cancer

Jan-

for

istic-of

and

observations

nucleic rapid

growth

Rats follows:

(Wistar,

N.J.,

and

when

the

were

sacrificed

AND METHODS

were used

pregnancy All

was

on

the

in

(500 &sxnole)++ to sacrifice

(Wistar);

observed

of Purina

Three

256;

rats

diet

day.

(Walker

young

a stock

tumors

fetuses

groups,

as

tumor

(Wistar);

from Barkbridge

Walker Farms,

Chow.

were

performed

actively.

growing

tissues,

“mammogenic”

obtained

be

on

con-

fetal

Furth

were

to

in this

experimental

animals

transplanted

on the 17th

minced,

AxC);

as

tumor).

in different

Fisher,

character-

rats,

reported

MATERIALS

of

in non-neoplastic

and pregnant

“mammogenic”

maintained

tumor

Animals

and

utilization

that

observations

here

previously

not

(Fistar,

Fisher).

anabolism

are adding (4 weeks)

view

may be a metabolic

pituitary

(AxC);

involving

Studies

tumors

adults

were

We

strains

hepatoma

tumor

prior

protein

Furth

of three normal

(Fisher)8

analysis,

or stimulated

of young

lymphosarcoma;

to the

in the rat

transplantable

three

rise

given

synthesis

tissues.

on the livers

Murphy

have

acid

as neoplastic

nection

K.E.Paschkis

31, 1961

Previous

well

and

of Biochemistry and Medicine, and Division of Endocrine Research, Jefferson Medical College, Philadelphia, Pa.

Received

uracil

T.L.Williams,

at a time

The pregnant were

pooled

for

rats

each

and.homogenired. all

experimental

groups

received

in 10 ml of 0.85% NaCl solution by cervical

fracture

and

20 mg.

of uracil-2-C14

intraperitoneally

decapitation;

previous

18

hours

studies

*This work was supported in part by a grant (C-1307) from the National Cancer Institute, National Institutes of Health, U.S.Public Health Service. **Obtained from the New England Nuclear Corp., Boston, Mass., on allocation by the U.S.Atomic Energy Commission. 156

Vol.

4, No. 2,1961

BIOCHEMICAL

AND

showed maximum incorporation (Rutman situ

et al.,

with

excised

cold

0.2%

and placed

The livers homogenized nizer.

sucrose

were

a gas-flow

counter

sucrose

at

this

about

the livers

were

time

perfused

subcutaneous

Samples

to *5 per

minced

dry,

(1:lO)

in

tumors)

cent

scissors,

on individual

et al., were

with

were

and

in a Potter-Elvehjem

in duplicate

(Herbert

manner.

acids

and (also

blotted

performed

RNA was isolated

in conventional

solution

in 0.25M

were

nucleic

COMMUNICATIONS

ice.

and tumors

at O’C.

RESEARCH

exsanguination,

on cracked

Analyses

tumors.

in liver After

1954).

BIOPHYSICAL

1957)

plated

homoge-

livers

and analyzed

by evaporation

and

(Allen,

1940)

and counted

in

accuracy.

RESULTS AND DISCUSSION The pertinent purposes

of comparison,

neoplastic,

are

et al.,

and female

1958).

Wistar

normal

rats,

presented

findings

and regenerating

Cantarow

either

data

in the table,

reported

liver,

nor between

or regenerating

I

The activity Walker

256 tumor

for (Rutman

difference

includes, normal et al.,

was found

male Wistar,

Fisher,

for adult, 1954;

between

AxC rats

and

pre-

male in

liver.

Specific Activity of RNA after of 20 mg. Uracil-2-Cl4 (3.3

*Figures #Specific

previously

and hepatoma

No significant

which

intraperitoneal Injection x 106 counts/min./mg.)

-

in parenthesis indicate numbers of animals activity values are means, with mean deviations

of uracil and Murphy

incorporation

in

lymphosarcoma

was of the same order

157

fetai

tissues

and

in the of magni-

Vol. 4, No. 2,1961

tude

as

had

been

ing

these

the

concept

tumors

protein

that

with and

tivity

of this

and/or

accelerated

and

thymine

young

rat

were

and

the values this

lower

animals.

comparatively ing

activity

This

is the

bearing

this

tumor

ulated

growth

This

(Cantarow

conditions.

et

for first

tumors

This

possibility

may

that

and

Bojarski, 1960)

ac-

wt.

that

growth

RNA

in the livers

act

differently

is

being

livers

adult

of other

tumorof

wt.

(?)

hormone,

by which

of normal different

adult

grow-

of rats

of the markedly liver

hormone

under

normal

the livers

to 5009;

of growth

the

RNA of an actively

in view up

for

and

we have encountered

with

obtained

(body

tumor

into

striking

production

1958),

with

in accord,

Stocken,

and livers

of uracil

animals

al.,

and

bear-

of increased

(Hiatt

those

than

instance

particularly

into

in accord

They are

“manmogenic”

higher

other

the possibility

of uracil

(Stevens

the

low values

to active

suggests

incorporation

are

of these

due presumably

for

incorporation

The relatively

tumor.

of rats

to states

kinase

and

liver.

although

those

livers

of RNA.

thymidylate

liver,

are

is related

catabolic

obtained

than

in the findings

turnover

of high

tumor,

limited

pathway

COMMUNICATIONS

regenerating

also

These

rats.

low uracil

bearing

bearing

pregnant

RESEARCH

liver, occurred

reports

However,

liver,

of

BIOPHYSICAL

preneoplastic

the recent

in fetal

of rats

AND

incorporation

and

anabolism

1960)

for

found

Increased

hepatoma.

too,

BIOCHEMICAL

to 24g.),

up the

stim-

tumor.

stimulates rats experimental

investigated.

REFERENCES Allen, R.J.L., Biochem. J. s, 858 (1940) Cantarow,A., Williams,T.L., Melnick, I., and Hiatt,H.H. Herbert,E., Rutman,R.J., Schneider, Stevens,L.

Paschkis,K.E., Cancer Research Is, 818 (1958) and Bojarski,T.B., Biochem. Biophys. Research Corn. 2, 35 (1960) Potter,V.R., and Hecht,L.I., J.Biol. Chem. a, 659 (1957) Cantarow,A., and Paschkis,K.E., Cancer Research 14, 119 (1954) W.C., J. Biol. Chem. 1pL, 293 (1945) and Stocken,L.A., Biochem. Biophys. Research Corn. 2, 155 (1960)

158