Accession Number : AD0676430

Title :   THE RADIOMIMETRIC ACTION OF VALINOMYCIN ON THE NUCLEAR STRUCTURE OF RAT THYMOCYTES,

Corporate Author : NATIONAL RESEARCH COUNCIL OF CANADA OTTAWA (ONTARIO) DIV OF RADIATION BIOLOGY

Personal Author(s) : Whitfield,J. F. ; Perris,A. D.

Report Date : 02 OCT 1967

Pagination or Media Count : 11

Abstract : Low concentrations (1.3 x 10 to the minus 10th power to 2.6 x 10 to the minus 10th power M) of the antibiotic valinomycin stimulate cellular respiration and initiate in inorganic phosphate-dependent metabolic reaction which causes the disaggregation of the highly condensed chromatin structures in the nucleus of the unirradiated and irradiated rat thymocyte into a structureless ('pycnotic') nucleoprotein mass. This action of valinomycin can be prevented by 2,4 dinitrophenol or reducing the extracellular inorganic phosphate concentration. The action of valinomycin on the thymocyte very closely resembles that of ionising radiation. Comparison of the known metabolic effects of radiation with those of valinomycin, parathyroid hormone and 2,4 dinitrophenol reveals a characteristic metabolic pattern which can explain the loss of nuclear structure in irradiated thymocytes. (Author)

Descriptors :   (*NUCLEI(BIOLOGY), *RADIATION EFFECTS), (*ANTIBIOTICS, *CELL STRUCTURE), ADENOSINE PHOSPHATES, DEGRADATION, METABOLISM, RADIOBIOLOGY, NUCLEOPROTEINS, CANADA

Subject Categories : Radiobiology
      Pharmacology

Distribution Statement : APPROVED FOR PUBLIC RELEASE