The results on the research of SMMC-7721 cultured human hepatoma cells showed that both 10nmol/mL of exogenous GM3 and 1nmol/mL of exogenous GD3 could stimulate a transient rapid increase of [Ca2+]i, and it took 45sec to reach the maximum value of [Ca2+]i.After one addition of GM3 or GD3 ,[Ca2+]i would recover to control level within 2-3 minutes. Treatments with interval addition of GM3 or GD3 in different situation, the increase of [Ca2+]i in duced by GM3 depended on the releasing of Ca2+ from ER and influxing of Ca2+; on the other hand, by GD3 showed no relationship with these two systems. Further studies demonstrated that when [Ca2+]i reached maximum level , the concentration of IP3 (1 , 4 , 5) was increased 9. 3 folds and cAMP, 82%, as compared with control. By the treatment of 1nmol GD3 , IP3 (1 , 4, 5) was only raised slightly (82%). These results might suggest that there are different mechanisms of increasing [Ca2+]i between GM3 and GD3.
Cui,Wen; Liu, Yin-kun; Gu ,Bo-jun; Chen ,Rui-qun.
A Primary Report on The Changes of lnositol-1 , 4 , 5-Triphosphate and cAMP of SMMC-7721 Cultured Human Hepatoma Cells by GM_3 and GD_3[J]. Chinese Journal of Biochemistry and Molecular Biology, 1994, 10(05): 549-552