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6772188 
Journal Article 
Lead reduces depolarization-induced calcium entry in cultured DRG neurons without crossing the cell membrane: Fura-2 measurements 
Domann, R; Wunder, L; Busselberg, D 
1997 
Yes 
Cellular and Molecular Neurobiology
ISSN: 0272-4340
EISSN: 1573-6830 
17 
3 
305-314 
English 
9187487 
WOS:A1997XC67600003 
1. Cultured dorsal root ganglion of rat pups were depolarized by exposure to 50 mM K+ and the rise of [Ca2+]i was measured using fura-2 as an indicator. 2. Lead in the extracellular solution reduced the rise of [Ca2+]i in a concentration-dependent manner, with a threshold concentration of 0.25 microM. More than 80% of the calcium entry was prevented by approximately 5 microM lead. The IC50 and the Hill coefficient were 3.1 microM and 1, respectively. 3. This effect was considered to be due to a reduction of VACCCs, since applications of NMDA did not result in any rise of [Ca2+]i. 4. Since Pb2+ itself changes the fura-2 signal in a typical and characteristic manner, fura-2 is also an indicator for Pb2+. No changes in fura-2 signals were detected when lead (5 microM) was applied for several minutes in the absence of calcium, indicating that Pb2+ did not enter the cells. 5. Thus it is concluded that lead prevents calcium entry by reducing VACCCs but does not cross the cell membrane itself. 
fura-2; Pb2+ neurotoxicity; dorsal root ganglia; cell cultures