Researchers decipher key molecule for onset of addiction
Modena/London – Researchers from Germany, Italy and the UK have
identified a molecule that is key to the onset of addiction and also
involved into memory formation (EMBO Journal, doi:10.1038/emboj.2010.279). According to results of the team headed by Pierluigi Nicotera, expression of the type 2 ryanodine receptor (RyR2) leads to sustained increase of calcium in nerve cells, the signal responsible for rearrangement of brain connections. When the researchers blocked the Ca2+ release channel present on the endoplasmic reticulum in a mouse model for onset of drug dependence, sensitization to nicotine-induced habituated locomotion was abolished. The researchers conclude that gene-dependent reprogramming of Ca2+ signalling is involved in nicotine- or cocaine induced behavioural changes. RyR2 upregulation was itself required for long-term phosphorylation of CREB in a positive-feedback signalling loop.