Clinical neuroendocrinology and neuropharmacology of alcohol withdrawal.

A number of alcohol research groups have measured anterior and posterior pituitary hormones, the endogenous opiates, CNS peptides, and putative neurotransmitters during alcohol withdrawal. The data are often complex and contradictory, though a number of themes have emerged. Activity of the hypothalamic-pituitary-adrenal axis (HPA) is increased during chronic alcohol exposure and appears to remain altered for at least 2 to 4 weeks after cessation of drinking. There is increased turnover of norepinephrine and enhanced binding of CNS adrenergic receptors. By contrast, there are decreases in CNS activity of select endogenous opiates and GABA. Other CNS compounds that may play a role in alcohol withdrawal are prolactin, thyrotropin-releasing hormone (TRH), vasopressin, cyclic 3'5'-adenosine monophophate (cAMP), Delta-sleep-inducing peptide (DSIP), and iron. Despite many studies in humans and animals, the roles of CNS dopamine and serotonin in withdrawal remain unclear. A number of peptides, including cholecystokinin (CCK), neurotensin, and bombesin, have been shown to interact with the CNS actions of alcohol and may play a role in alcohol withdrawal. Inadequate work has been performed on acetylcholine (ACh), human growth hormone (HGH) and luteinizing hormone (LH). Studies of the recently identified GABA-benzodiazepine-barbituate receptor complex indicate that this system is likely to be involved in the pathophysiology of alcohol withdrawal. Perturbation studies with corticotropin-releasing factor (CRF) and TRH (with measures of ACTH and cortisol and TSH and prolactin, respectively), may identify patients with withdrawal-related autonomic dysfunction.