naloxone and Tourette-Syndrome

Topics: Behavior; Humans; Naloxone; Neurosecretory Systems; Tourette Syndrome

The purpose of this study was to replicate findings from an earlier pilot study in which we found a dose-related effect of the opioid antagonist naloxone on tic behavior in patients with Tourette's syndrome (TS). Fifteen subjects with TS were challenged with randomized doses (30 and 300 microg/kg) of naloxone at 3-day intervals. Videotaped recordings of tic behavior were counted in a "blind" fashion. We found that naloxone had opposite effects on tics at different dosages. The low dose caused a significant decrease in tics, whereas the high dose caused a significant increase in tics. Therefore, activity at opioid receptors appears to influence the expression of TS, and the difference in response to naloxone in TS subjects may be based on a dose-response effect.

Topics: Adult; Dose-Response Relationship, Drug; Double-Blind Method; Drug Administration Schedule; Humans; Male; Middle Aged; Naloxone; Narcotic Antagonists; Receptors, Opioid; Tic Disorders; Tourette Syndrome; Treatment Outcome

It has been proposed that Tourette syndrome is associated with dysfunction in widespread cortical areas and globus pallidus externus hyperactivity secondary to dopaminergic hyperactivity and serotonergic/dynorphinergic hypoactivity. The main objective of this study was to test this hypothesis by developing an animal model of Tourette syndrome via striatotomy, followed by administration of drugs that mimic the neurotransmitter environment, so as to induce globus pallidus externus hyperactivity.. Rats were assigned to 3 groups: stereotactic striatotomy (STT) and striatal sham -lesion (SHAM) groups, treated with anterior and posterior striatum procedures in both hemispheres, and a group of nonoperated animals (NAIVE). Postoperatively, all rodents were blindly administered 3 drug protocols: levodopa/benserazide; levodopa/benserazide/ergotamine/naloxone (MIX); and saline. The animals were filmed at the peak action of these drugs. The videos were evaluated by a single blinded researcher.. Six types of involuntary movements (IMs) were observed: cephalic, trunk jerks, oromandibular, forepaw jerks, dystonic, and locomotive. The number of animals with IM and the mean number of IM after both levodopa/benserazide and MIX was significantly higher in the STT compared with the SHAM and NAIVE groups. In the SHAM and NAIVE, MIX was superior to levodopa/benserazide in the induction of IM. In the STT, MIX was superior to levodopa/benserazide in the induction of trunk jerks. Appendicular IM were more common after posterior than after anterior striatotomy.. These results show that striatotomy, followed by administration of levodopa/benserazide alone or associated with ergotamine and naloxone, is efficacious in inducing IM, supporting the hypothesis that led to this study.

Topics: Analgesics, Non-Narcotic; Animals; Benserazide; Corpus Striatum; Dopamine Agents; Double-Blind Method; Drug Combinations; Ergotamine; Female; Globus Pallidus; Levodopa; Naloxone; Prospective Studies; Rats; Rats, Wistar; Stereotaxic Techniques; Tourette Syndrome

The selective serotonin (5-HT) reuptake inhibitors (SSRIs) represent the first-line pharmacotherapy for obsessive-compulsive disorder (OCD), and atypical antipsychotic drugs, which block 5-HT2A receptors, are used in augmentation strategies. Opiate drugs are also effective in treatment-refractory OCD and Tourette syndrome. The 5-HT2A-related behavior (i.e., head twitch) has been related with tics, stereotypes, and compulsive symptoms observed in Tourette syndrome and OCD.. The aim of this study was to explore whether 5-HT2A-related behavior is affected by atypical opiate drugs.. Head-twitch response was induced in mice by administration of either 5-hydroxytryptophan (5-HTP) or the 5-HT2A/C agonist (+/-)-1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane (DOI). Dose-effect curves of atypical opiate drugs [(+/-)-tramadol, (-)-methadone and levorphanol], morphine, and other psychoactive drugs (fluvoxamine, desipramine, nefazodone, and clozapine) were performed. Opioid mechanisms were investigated by administration of naloxone.. All the opiates tested reduced both 5-HTP and DOI-induced behavior in a naloxone-reversible fashion, atypical opiates being more effective. The effects of the other drugs depended on the protocol, clozapine being the most effective.. Combined 5-HT and opioid properties result in a greater efficacy in antagonizing 5-HT2A-related behavior. These results provide behavioral evidence to support convergent effects of the 5-HT and opioid systems in discrete brain areas, offering the potential for therapeutic advances in the management of refractory stereotypes and compulsive behaviors.

Topics: 5-Hydroxytryptophan; Analgesics, Opioid; Animals; Clozapine; Desipramine; Disease Models, Animal; Dose-Response Relationship, Drug; Fluvoxamine; Indophenol; Levorphanol; Male; Methadone; Mice; Morphine; Naloxone; Narcotic Antagonists; Obsessive-Compulsive Disorder; Piperazines; Receptor, Serotonin, 5-HT2A; Receptor, Serotonin, 5-HT2C; Stereotyped Behavior; Tics; Tourette Syndrome; Tramadol; Triazoles

Currently the most prevailing hypothesis attempting to explain the pathophysiology of Tourette's syndrome (TS) suggests that the disease results from dopaminergic (DA) hyperactivity (Golden, 1986). Evidence for this hypothesis is indirect and includes the favorable response of these patients to haloperidol, exacerbation of symptoms with dopaminergic drugs (e.g., methylphenidate) and the findings of reduced DA metabolites in the CSF of some TS patients (Singer et al., 1982). We have recently suggested that deranged opioid functions may also be important in the pathophysiology of TS (Sandyk, 1985). Our hypothesis was based on the favorable response of a subgroup of patients to administration of opiate antagonists (e.g., naloxone, naltrexone) (Sandyk et al., 1986), and is also supported by a recent finding demonstrating depletion of striatal dynorphins in a subject with TS (Haber et al., 1986). Furthermore, based on several clinical features of the disease, we have recently suggested that the hypothalamus could be a site of dysfunction in the disease (Sandyk et al., 1986). To investigate the possible role of deranged opioid-mediated hypothalamic functions in TS further, we tested the effects of acute naloxone (Nx) challenge on plasma FSH and LH levels in 5 male TS patients (aged 11-16 years) and in 4 non-TS-diseased controls (narcoleptics). The plasma FSH and LH levels were drawn prior to and 30 min following the intramuscular administration of 1.2 mg of naloxone.

Topics: Adolescent; Child; Endorphins; Follicle Stimulating Hormone; Gonadotropins; Humans; Luteinizing Hormone; Male; Naloxone; Narcolepsy; Tourette Syndrome

Topics: Adolescent; Adult; Aged; Female; Growth Hormone; Humans; Male; Middle Aged; Naloxone; Tourette Syndrome

The release of corticotrophin-releasing factor (CRF) in the human has been shown to be under a direct inhibitory control derived from the locus coeruleus (LC). Opioids have been shown to inhibit CRF release. Based on our hypothesis of deranged opioid-noradrenergic activity in Tourette's syndrome (TS), we studied the effect of a naloxone challenge on plasma cortisol levels in 6 TS patients. In all patients naloxone produced a significant rise in cortisol secretion. These results support our hypothesis and suggest that in TS, noradrenergic LC receptors involved in CRF release are supersensitive as a result of chronic excessive endorphinergic activity.

Topics: Adolescent; Adult; Aged; Child; Female; Humans; Hydrocortisone; Male; Middle Aged; Naloxone; Time Factors; Tourette Syndrome

Topics: Adult; Humans; Male; Naloxone; Tourette Syndrome

Topics: Adolescent; Child; Compulsive Behavior; Humans; Naloxone; Obsessive Behavior; Tourette Syndrome

Topics: Adolescent; Child; Child, Preschool; Female; Growth Hormone; Humans; Male; Naloxone; Tourette Syndrome

Topics: Adolescent; Animals; Humans; Male; Naloxone; Rats; Receptors, Opioid; Substance Withdrawal Syndrome; Tourette Syndrome

Topics: Adolescent; Child; Endorphins; Humans; Male; Naloxone; Tourette Syndrome

Topics: Adolescent; Double-Blind Method; Humans; Infusions, Parenteral; Male; Naloxone; Tourette Syndrome

Topics: Adult; Humans; Male; Naloxone; Tourette Syndrome