DIFFERENCES IN RADIOSENSITIVITY AND RECOVERY FROM THE EFFECTS OF RADIATION BETWEEN TWO TYPES OF ASCITES HEPATOMA IN THE RAT

Journal Article · Thu Jan 01 04:00:00 EST 1959 · Nippon Igaku Hoshasen Gakkai Zasshi (Japan)

OSTI ID:4843765

Masayama, S

Two new types of ascites hepatoma, AH 7974 and AH 130, were derived in the rat and transplanted successively throughout numbers of generations. The former is characterized by high resistance to nitrogen mustard compounds, while the latter is very sensitive to these chemical agents. These tumors were maintained in ascites and inoculated subcutaneously on the backs of the animals 8 to 10 days before the experiments. P/sup 32/ (60 mu c per animal) was injected intraperitoneally 1 hour before sacrifice. Preliminary experiments revealed that a pronounced depression of the uptake of P/sup 32/ was produced by x radiation. This effect was used as an indicator in differentiating the responses of the 2 hepatomas to x radiation. Analysis of the distribution of the radioactivity into the various phosphate fractions of tumor tissues (acid-soluble, lipid, nucleic acids, and phosphoprotein phosphorus) one hour after intraperitoneal injection showed almost exclusive incorporation of P/sup 32/ into the acid-soluble fraction. Detailed analysis of the acidsoluble fraction by ion exchange column chromatography demonstrated that about 80% of the radioactivity was present in the inorganic phosphate and 20% was distributed in other phosphorylated compounds: adenosine triphosphate, adenosine diphosphate, and adenosine monophosphate. After x radiation, the radioactivity in the inorganic phosphate was decreased. One hour after intraperitoneal administration of P/sup 32/ almost all the radioactivity is present as inorganic phosphate and the depression of P/ sup 32/ uptake of whole tumor tissue by radiation is chiefly due to depression of incorporation of P/sup 32/ into inorganic phosphate. The radioactivity of the whole tumor tissue one hour after the intraperitoneal injection of 60 mu c of P/ sup 32/ was measured at different intervals following whole body radiation (1000 r) to the tumor-bearing animals. Comparison of the time course of inhibition and subsequent recovery was made on the 2 strains of the hepatoma. In the AH 130 hepatoma x radiation caused a pronounced inhibition of P/sup 32/ uptake, but a rapid recovery followed by an increase of P/sup 32/ uptake was observed abeut 12 hours after radiation. On the other hand, in the AH 7974 inhibition of P/sup 32/ uptake was rather small as compared to AH 130 and slow recovery from the initial inhibition was noted. These results were discussed in relation to the fractionation of the dose in the radiotherapy of malignant tumors. (Abstr. Japan Med., 1: No. 10, 1961)

• Research Organization: Tokyo Univ.
• NSA Number: NSA-15-027450
• OSTI ID: 4843765
• Journal Information: Nippon Igaku Hoshasen Gakkai Zasshi (Japan), Journal Name: Nippon Igaku Hoshasen Gakkai Zasshi (Japan) Vol. Vol: 19; ISSN NHGZA
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

BIOLOGY AND MEDICINE
BODY
CHEMICALS
CHROMATOGRAPHY
ION EXCHANGE
IRRADIATION
LIPIDS
LIVER
NUCLEIC ACIDS
PHOSPHATES
PHOSPHORUS 32
PROTEINS
QUANTITY RATIO
RADIATION DOSES
RADIATION EFFECTS
RADIOSENSITIVITY
RADIOTHERAPY
RATS
RECOVERY
TISSUES
TRANSPLANTS
TUMORS
WHOLE-BODY IRRADIATION
X RADIATION