Effects of four inorganic lead compounds on the proliferation and junctional coupling of cultured REL liver cells.
BACKGROUND
Chronic, low-level exposure to inorganic lead (Pb) has been involved in a number of human diseases, including tumors. In this study, the effect of four different inorganic Pb compounds (acetate, chloride, monoxide, and sulfate) was evaluated, in vitro, on liver-derived REL cells, known to be very sensitive to tumor promoters.


METHODS
Cytotoxicity and effects on intercellular communication (GJIC) were evaluated, respectively, by cell- density/proliferation and dye-transfer assays. Pb concentration in the media solutions used for each treatment was quantified by atomic absorption spectroscopy-electrothermal atomization.


RESULTS
Each of the Pb compounds we tested showed a typical dose- and time-related effect on REL cell proliferation, this effect not being related to the free metal concentration. Contrary to classical tumor promoters, none of the compounds significantly affected REL GJIC (1-hour treatment).


CONCLUSIONS
Our results are indicative of specificity in the effects of the different Pb compounds. The mechanism(s) of their action need further investigations.
Apostoli
P
P
Institute of Occupational Health, School of Medicine, University of Brescia, Brescia, Italy.
Huard
C
C
Chaumontet
C
C
Martel
P
P
Alessio
L
L
Mazzoleni
G
G
D000818:Animals; D002273:Carcinogens / Q000009:adverse effects*; D002450:Cell Communication / Q000187:drug effects; D002452:Cell Count; D002455:Cell Division / Q000187:drug effects; D002460:Cell Line / Q000187:drug effects / Q000473:pathology; D004848:Epithelium / Q000187:drug effects / Q000473:pathology; D007365:Intercellular Junctions / Q000187:drug effects; D007854:Lead / Q000009:adverse effects*; D008099:Liver / Q000187:drug effects* / Q000473:pathology*; D009942:Organometallic Compounds / Q000009:adverse effects; D010087:Oxides / Q000009:adverse effects; D051381:Rats
D002273:Carcinogens; D009942:Organometallic Compounds; D010087:Oxides; D007854:Lead; C029891:lead chloride; C047365:lead oxide; C032722:lead sulfate; C008261:lead acetate