Biological effects of exogenous adenosine 5 prime -triphosphate on cultured mammalian cells: Evidence for a receptor mechanism and its regulation by desensitization

Thesis/Dissertation · Sun Jan 01 04:00:00 EST 1989

OSTI ID:6277717

Gonzalez, F A

Exogenous adenosine 5{prime}-triphosphate (ATP) mobilized intracellular calcium in human carcinoma A43l cells and in Swiss 3T3 and 3T6 mouse fibroblasts by increasing inositol trisphosphate similar to well down growth factors (platelet-derived growth factor (PDGF), epidermal growth factor (EGF), bradykinin (BK), serum). Calcium mobilization was examined by video imaging of fura-2 fluorescence is single cells, following the radioactive isotope {sup 45}Ca, and monitoring the decrease in fluorescence of cells loaded with chlortetracycline. Uridine 5{prime}-triphosphate, but not other nucleotides, mimicked ATP. Single-cell analysis revealed synchronous responses in 10 sec to ATP, BK or serum, while PDGF (3T3) and EGF (A431) produced slower signals with significant cell-to-cell variation. PDGF desensitized 3T3 cells to ATP and BK added 100 sec later but ATP or BK did not desensitized to PDGF. Homologous desensitization was seen with all agonists. Heterologous desensitization was also observed in A431 cells where ATP desensitized to serum, but serum did not to ATP. ATP-stimulated calcium entry was detected after 10 sec in A431 cells, but not in Swiss 3T6 cells. Entry started before significant efflux had occurred and did not fit the capacitance model of Putney. A 2-3 hr ATP pretreatment produced a homologous desensitization state that required 20 hr to disappear, probably due to down-regulation of the putative ATP receptors.

• Research Organization: Cornell Univ., Ithaca, NY (USA)
• OSTI ID: 6277717
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ALKALINE EARTH ISOTOPES
ALKALINE EARTH METAL COMPOUNDS
ANIMAL CELLS
ANIMALS
ATP
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BIOCHEMICAL REACTION KINETICS
CALCIUM 45
CALCIUM COMPOUNDS
CALCIUM ISOTOPES
CELL CULTURES
CONNECTIVE TISSUE CELLS
DAYS LIVING RADIOISOTOPES
ENZYMES
EVEN-ODD NUCLEI
FIBROBLASTS
FLUORESCENCE
GROWTH FACTORS
INTERMEDIATE MASS NUCLEI
ISOTOPE APPLICATIONS
ISOTOPES
KINETICS
KININS
LUMINESCENCE
MAMMALS
MAN
MEMBRANE PROTEINS
MEMBRANE TRANSPORT
MICE
MITOGENS
NUCLEI
NUCLEOTIDES
ORGANIC COMPOUNDS
PEPTIDES
PHOSPHORUS-GROUP TRANSFERASES
PHOSPHOTRANSFERASES
POLYPEPTIDES
PRIMATES
PROTEINS
RADIOISOTOPES
REACTION KINETICS
RECEPTORS
RODENTS
SOMATIC CELLS
TRACER TECHNIQUES
TRANSFERASES
VERTEBRATES