In vitro pharmacology of metaiodobenzylguanidine uptake, storage and release in human neuroblastoma cells
Montaldo, P.G.; Carbone, R.; Lanciotti, M.; Ponzoni, M.; Cornaglia-Ferraris, P.
Journal of Nuclear Biology and Medicine 35(4): 195-198
1991
ISSN/ISBN: 0368-3249 PMID: 1823817 Document Number: 381830
Four human neuroblastoma (NB) cell lines (LAN-5, SK-N-BE(2)C, GI-LI-N, and GI-CA-N) have been investigated for their ability to take up and store [125I]metaiodobenzylguanidine (125I-MIBG) in vitro. Only SK-N-BE(2)C and LAN-5 cells were able to specifically take up MIBG, with the former cell line showing a more efficient retention of the radiotracer. 125I-MIBG incorporation in both cell lines was inhibited by norepinephrine, desipramine, ouabain and energy depletion. Thus, all the major criteria for specific (type 1) uptake were fulfilled. Conversely, GI-LI-N and GI-CA-N cells did not show any specific uptake. Pharmacological manipulations aimed at defining the intracellular site(s) of 125I-MIBG storage clearly showed that the radiotracer is not accumulated in the reserpine-sensitive neurosecretory granules and vesicles in NB cells, contrary to what has been observed in a chromaffin derived tumor cell line (PC12). Our study provides new and suitable models to investigate in vitro the molecular and cellular pharmacology of MIBG in NB cells.