Opioid antagonists and alcoholism treatment

Dansyl-PQRamide, a putative antagonist of NPFF receptors, reduces anxiety-like behavior of ethanol withdrawal in a plus-maze test in rats

Much evidence indicates that endogenous opioid peptides are involved in effects caused by ethanol. The aim of the present study was to determine whether dansyl-PQR amide, a putative antagonist of receptors for an anti-opioid peptide-neuropeptide FF (NPFF) could affect anxiety-like behavior measured during withdrawal from acute-, and chronic ethanol administration in the elevated plus maze test in rats. Our study indicated that intracerebroventricular (i.c.v.) administration of dansyl-PQRamide (2.4 and 4.8 nmol) reversed anxiety-like behavior measured as a percent time spent in the open arms, and a percent open arm entries onto the open arms in the elevated plus-maze test in rats. These effects were inhibited by NPFF (10 and/or 20 nmol, i.c.v.) in the experiments performed during withdrawal from acute- and chronic ethanol administration. During withdrawal from acute ethanol, naloxone (1mg/kg, i.p.), a nonselective opioid receptor antagonist, attenuated only an increased percent time spent in the open arms induced by dansyl-PQR amide (4.8 nmol). Dansyl-PQR amide, NPFF and naloxone given alone to naive rats did not have influence on spontaneous locomotor activity of animals. Furthermore, NPFF potentiated anxiety-like behavior during withdrawal from chronic, but not acute, ethanol administration in rats. Our data suggest that NPFF system is involved in regulation of affective symptoms of ethanol withdrawal. It seems that involvement of the NPFF system in ethanol withdrawal anxiety-like behavior is associated with regulation of the opioid system activity.

Advances in the pharmacological treatment of pathological gambling

In the present paper we discuss the current status of drug treatment for pathological gambling and the scientific rationales underlying the various pharmacological approaches. Specifically, we summarize the treatment study results of serotonin reuptake inhibitors, mood stabilizers, opioid antagonists, and atypical antipsychotics in pathological gambling. We also discuss dosage strategies, the duration of treatment, issues surrounding medication compliance, and approaches to treatment-refractory pathological gambling, such as pharmacological and behavioral augmentation.

Combination pharmacotherapy in alcoholism: a novel treatment approach

Combination pharmacotherapy has proven effective in a number of psychiatric disorders, including depression and schizophrenia. However, compared with other affective disorders, few studies have explored the use of combination therapy in alcoholism, and the majority have been limited to animal models. There is evidence to support a role for combination therapy in alcoholism. For example, several neurochemical systems, including the dopaminergic, serotonergic, and opioidergic, appear to affect alcohol intake. Studies in several different types of alcohol-preferring rats have suggested that coadministration of agents to target more than one of these systems simultaneously may produce beneficial effects on alcohol intake, while avoiding problematic effects, such as alterations in food or water intake. Data from preliminary clinical studies have shown trends toward combination therapy reducing alcohol intake in humans. While such findings are encouraging, they must be explored further in larger, randomized, double-blind trials.