title: A simple and rapid method for standard preparation of gas phase extract of cigarette smoke.
abstract: Cigarette smoke consists of tar and gas phase: the latter is toxicologically important because it can pass through lung alveolar epithelium to enter the circulation. Here we attempt to establish a standard method for preparation of gas phase extract of cigarette smoke (CSE). CSE was prepared by continuously sucking cigarette smoke through a Cambridge filter to remove tar, followed by bubbling it into phosphate-buffered saline (PBS). An increase in dry weight of the filter was defined as tar weight. Characteristically, concentrations of CSEs were represented as virtual tar concentrations, assuming that tar on the filter was dissolved in PBS. CSEs prepared from smaller numbers of cigarettes (original tar concentrations ≤ 15 mg/ml) showed similar concentration-response curves for cytotoxicity versus virtual tar concentrations, but with CSEs from larger numbers (tar ≥ 20 mg/ml), the curves were shifted rightward. Accordingly, the cytotoxic activity was detected in PBS of the second reservoir downstream of the first one with larger numbers of cigarettes. CSEs prepared from various cigarette brands showed comparable concentration-response curves for cytotoxicity. Two types of CSEs prepared by continuous and puff smoking protocols were similar regarding concentration-response curves for cytotoxicity, pharmacology of their cytotoxicity, and concentrations of cytotoxic compounds. These data show that concentrations of CSEs expressed by virtual tar concentrations can be a reference value to normalize their cytotoxicity, irrespective of numbers of combusted cigarettes, cigarette brands and smoking protocols, if original tar concentrations are ≤15 mg/ml.
authors.affiliation: Department of Cellular Pharmacology, Graduate School of Medicine, Hokkaido University, Sapporo, Hokkaido, Japan.
authors.forename: Tsunehito
authors.initials: T
authors.lastname: Higashi
authors.affiliation: Department of Cellular Pharmacology, Graduate School of Medicine, Hokkaido University, Sapporo, Hokkaido, Japan.
authors.forename: Yosuke
authors.initials: Y
authors.lastname: Mai
authors.affiliation: Central Institute of Isotope Science, Hokkaido University, Sapporo, Hokkaido, Japan.
authors.forename: Yoichi
authors.initials: Y
authors.lastname: Noya
authors.affiliation: Department of Cellular Pharmacology, Graduate School of Medicine, Hokkaido University, Sapporo, Hokkaido, Japan.
authors.forename: Takahiro
authors.initials: T
authors.lastname: Horinouchi
authors.affiliation: Department of Cellular Pharmacology, Graduate School of Medicine, Hokkaido University, Sapporo, Hokkaido, Japan.
authors.forename: Koji
authors.initials: K
authors.lastname: Terada
authors.affiliation: Department of Cellular Pharmacology, Graduate School of Medicine, Hokkaido University, Sapporo, Hokkaido, Japan.
authors.forename: Akimasa
authors.initials: A
authors.lastname: Hoshi
authors.affiliation: Department of Cellular Pharmacology, Graduate School of Medicine, Hokkaido University, Sapporo, Hokkaido, Japan.
authors.forename: Prabha
authors.initials: P
authors.lastname: Nepal
authors.affiliation: Department of Cellular Pharmacology, Graduate School of Medicine, Hokkaido University, Sapporo, Hokkaido, Japan.
authors.forename: Takuya
authors.initials: T
authors.lastname: Harada
authors.affiliation: Department of Cellular Pharmacology, Graduate School of Medicine, Hokkaido University, Sapporo, Hokkaido, Japan.
authors.forename: Mika
authors.initials: M
authors.lastname: Horiguchi
authors.affiliation: Department of Cellular Pharmacology, Graduate School of Medicine, Hokkaido University, Sapporo, Hokkaido, Japan.
authors.forename: Chizuru
authors.initials: C
authors.lastname: Hatate
authors.affiliation: Central Institute of Isotope Science, Hokkaido University, Sapporo, Hokkaido, Japan.
authors.forename: Yuji
authors.initials: Y
authors.lastname: Kuge
authors.affiliation: Department of Cellular Pharmacology, Graduate School of Medicine, Hokkaido University, Sapporo, Hokkaido, Japan.
authors.forename: Soichi
authors.initials: S
authors.lastname: Miwa
mesh_terms: D000818:Animals; D002021:Buffers; D045744:Cell Line, Tumor; D003603:Cytotoxins / Q000302:isolation & purification* / Q000633:toxicity; D005374:Filtration / Q000592:standards*; D005740:Gases / Q000737:chemistry*; D005898:Glass / Q000737:chemistry; D006801:Humans; D006838:Hydrocarbons / Q000302:isolation & purification; D010710:Phosphates / Q000737:chemistry; D051381:Rats; D012015:Reference Standards; D015203:Reproducibility of Results; D012906:Smoke / Q000009:adverse effects / Q000032:analysis*; D013696:Temperature; D013997:Time Factors; D062789:Tobacco Products / Q000032:analysis*
chemical_list: D002021:Buffers; D003603:Cytotoxins; D005740:Gases; D006838:Hydrocarbons; D010710:Phosphates; D012906:Smoke