Background:
In order to understand and generalize the toxic mechanism of cigarette smoke in living cells, comparison of the data between animal systems and other biological system such as microbial and plant systems is highly beneficial.

Objective:
By employing the tobacco cells as model materials for cigarette smoke toxicity assay, the impacts of the combustion by-products such as nitrogen oxides could be highlighted as the toxic impacts of the plantderived endogenous chemicals could be excluded in the plant cells.

Methods:
Cigarette smoke-induced cell death was assessed in tobacco cell suspension cultures in the presence and absence of pharmacological inhibitors.

Results:
Cigarette smoke was effective in induction of cell death. The smoke-induced cell death could be partially prevented by addition of nitric oxide (NO) scavenger, suggesting the role for NO as the cell death mediator. Addition of NO donor to tobacco cells also resulted in development of partial cell death further confirming the role of NO as cell death mediator. Members of reactive oxygen species and calcium ion were shown to be protecting the cells from the toxic action of smoke-derived NO.