|Budget Amount *help
¥1,800,000 (Direct Cost: ¥1,800,000)
Fiscal Year 1992: ¥300,000 (Direct Cost: ¥300,000)
Fiscal Year 1991: ¥1,500,000 (Direct Cost: ¥1,500,000)
A high performance liquid chromatographic method was established to measure polyamines (putrescine, cadaverine, spermidine, and spermine). Several troubles such as unstability of retention time of putrescine, unsatisfactory separation of putrescine from cadaverine, or emergence of air bubbles in the pumping system were dissolved by improvement of the mobile phase buffers, and refinement of the gradient program.
When K562 cells were cultured with polyamine synthesis inhibitors, difluoro methylornithine(DFMO) or methylglyoxal-bis-guanylhydrazone, cellular proliferation was inhibited, and polyamines were decreased, while viability of the cells stayed nearly 100%. The ratio of the killed cells to the alive cells(refered to as complement sensitivity) after the application of rabbit anti-K562 cell serum and guinea pig complement, was increased mainly as spermidine was decreased. Put rescine or spermine appeared not to be engaged in the complement sensitivity.
Transglutaminase(TGase) bridges protein to protein, and amines to protein. Polyamines also are natural substrates. TGase exists in every cell, and is activated by Ca^<2+>. Thus, it is expected to be activated when cell membrane is damaged by complement, because intracellular Ca^<2+> concentration is elevated by substantial amount of Ca^<2+> influx in the situation. Synergistic increase of the complement sensitivity was observed in the DFMO-cultured cells when the cells were further treated with TGase inhibitors, dansylcadaverine or amantadine. Taken together, it might be likely that the increased complement sensitivity of the K562 cells were resulted from the disturbance of the repair mechanism for the damage by complement.