(Budney et al. 1999, 2003, 2004), and the experience of these symptoms during abstinence is associated with rapid relapse to dependence (Cornelius et al. 2008). Withdrawal is accompanied by decreased mesocorticolimbic dopamine transmission, an effect mediated by decreased CB1 binding (Diana et al. 1998). Sensitivity to the acute effects of marijuana is genetically influenced (Lyons et al. 1997), and positive subjective reactions before the age of 16 predict later CD (Fergusson et al. 2003). Marijuana acutely increases heart rate (HR) (Kanakis et al., 1976), and heightened HR reactivity to other drugs is related to the genetic predisposition to SUD (Conrod et al. 1998). The acute effects of marijuana are mediated by CB1-induced increases in mesocorticolimbic dopamine release (Cooper and Haney 2008).
