HCRT and Abnormal emotional state: A human study found that plasma concentrations of orexin – which may reflect diffusion of the peptide between CNS and peripheral compartments (Kastin and Akerstrom, 1999) – during alcohol abstinence positively correlated with psychological distress levels (von der Goltz et al., 2011); thus, it is plausible that orexin modulates stress- or abstinence-related alcohol use.