Rubidium shows effects different from lithium on phosphatidylinositol metabolism in a cell line of human...

In a SK-N-BE human neuroblastoma cell line the incubation of rubidium (1 and 10 mM) for 24 h significantly increased IP2 formation, whereas it apparently did not affect other inositol phosphates. In comparison to lithium (10 mM), which significantly enhanced inositolmonophosphate and IP2 accumulation following carbamoylcholine (1 mM) stimulation, rubidium at the same concentration, was unable to affect inositol phosphate accumulation. In conclusion, the present experiments show that rubidium, compared with lithium, shows a different profile on phosphoinositide metabolism since its main action is an increase in phosphatidylinositol turnover. These results may have some relevance to the use of rubidium as antidepressant in man.