Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0036341 (schizophrenia)
 60,220 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The hypotheses of relative cholinergic underactivity in Huntington's disease, tardive dyskinesia, mania, and schizophrenia were pharmacologically investigated, using physostigmine and choline chloride. Intravenous physostigmine improved the involuntary movements of all of four patients with tardive dyskinesia and three of six patients with Huntington's disease. Physostigmine infusion also decreased manic symptoms in six of nine patients with mania, but had no beneficial effects in three patients with schizophrenia. Precursorloading with choline chloride may increase brain acetylcholine levels and central cholinergic activity. In patients with movement disorders a transient improvement during physostigmine infusion predicted a positive response to a trial of oral choline chloride. One manic patient may have been improved by choline chloride, however choline chloride did not improve symptoms in four of six schizophrenix patients. Chronic treatment with oral choline chloride increases plasma levels of choline during administration and for approximately 48 hr after discontinuation of treatment. A single 5-g dose of choline chloride also transiently raises plasma choline levels. These results with physostigmine support the hypotheses of cholinergic underactivity in Huntington's disease, tardive dyskinesia, and mania. Agents which might chronically increase cholinergic activity such as choline chloride should be further tested in these disorders.
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PMID:Pharmacological investigations of the cholinergic imbalance hypotheses of movement disorders and psychosis. 14 24

Jimson weed (Datura stramonium), is a wild growing herb that contains belladonna alkaloids. Recently there have been reports of intentional ingestion of Jimson weed by adolescents for psychedelic purposes. When seen in emergency department, these patients appear with physical signs of atropine-like poisoning, disturbances of thought and hallucinations. Diagnosis depends on a positive history, if available, and recognition of anticholinergic effects. Differentiation from lysergic acid diethylamide (LSD) ingestion and schizophrenia is important. Physostigmine, an anticholinergic agent, can reverse both central and peripheral manifestations of Jimson weed intoxication.
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PMID:Anticholinergic poisoning from Jimson weed. 93 12

There is evidence that reduced cholinergic activity may play a role in the pathophysiology of cognitive impairment in the schizophrenia spectrum. We tested the effects of physostigmine, an anticholinesterase inhibitor, on visuospatial working memory as evaluated by the Dot test, and on verbal learning and recall as measured by a serial learning task in patients with schizotypal personality disorder. Physostigmine tended to improve the Dot test, but not serial verbal learning performance in these patients.
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PMID:Physostigmine and cognition in schizotypal personality disorder. 1127 49

Enhancing cholinergic function has been suggested as a possible strategy for ameliorating the cognitive deficits of schizophrenia. The purpose of this study was to examine the effects of acetylcholinesterase (AChE) inhibitors in mice treated with the noncompetitive N-methyl-d-aspartate (NMDA) receptor antagonist, MK-801, which has been suggested as an animal model of the cognitive deficits of schizophrenia. Three separate experiments were conducted to test the effects of physostigmine, donepezil, or galantamine on deficits in learning and memory induced by MK-801. In each experiment, MK-801 (0.05 or 0.10 mg/kg) or saline was administered i.p. 20 min prior to behavioral testing over a total of 12 days. At 30 min prior to administration of MK-801 or saline, one of three doses of the AChE inhibitor (ie physostigmine-0.03, 0.10, or 0.30 mg/kg; donepezil-0.10, 0.30, or 1.00 mg/kg; or galantamine-0.25, 0.50, or 1.00 mg/kg) or saline was administered s.c. Behavioral testing was performed in all experimental animals using the following sequence: (1) spatial reversal learning, (2) locomotion, (3) fear conditioning, and (4) shock sensitivity. Both doses of MK-801 produced impairments in spatial reversal learning and in contextual and cued memory, as well as hyperlocomotion. Physostigmine and donepezil, but not galantamine, ameliorated MK-801-induced deficits in spatial reversal learning and in contextual and cued memory in a dose-dependent manner. Also, physostigmine, but not donepezil or galantamine, reversed MK-801-induced hyperlocomotion. Galantamine, but not physostigmine or donepezil, altered shock sensitivity. These results suggest that AChE inhibitors may differ in their capacity to ameliorate learning and memory deficits produced by MK-801 in mice, which may have relevance for the cognitive effects of cholinomimetic drugs in patients with schizophrenia.
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PMID:Cholinesterase inhibitors ameliorate behavioral deficits induced by MK-801 in mice. 1595 97

Cognitive impairment has the greatest impact on illness outcome in schizophrenia. The most significant challenge in schizophrenia therapeutics, thus, is to develop an efficacious treatment for cognitive impairments. Acetylcholinesterase inhibitors, such as Physostigmine and Rivastigmine, are considered effective treatments for cognitive decline in Alzheimer's Disease, where the loss of cholinergic neurons is thought to be responsible for various cognitive deficits. The current study investigated the cognitive effects of Rivastigmine given as an add-on therapy to antipsychotic-treated schizophrenia patients in a placebo-controlled double-blind design. The study initially involved 40 patients, of which 21 patients (11 assigned to Rivastigmine and 10 assigned to placebo) agreed to continued participation, remained on the study drug, and underwent assessment of executive functioning, verbal skills, verbal and spatial working memory, attention and psychomotor speed on three occasions: (i) at baseline, and then (ii) after 12 weeks and (iii) 24 weeks of treatment with placebo or Rivastigmine. The results failed to reveal significant improvement on any cognitive measure with Rivastigmine treatment, compared with the placebo treatment. Some cognitive variables showed significant practice effects in both the placebo and Rivastigmine groups. No effects were noted in symptoms or side effects ratings. The beneficial cognitive effects of Rivastigmine seen in an open-label preliminary study are not substantiated by this study. Future studies should investigate the effects of other procholinergic drugs, such as Galantamine, which also act on the nicotine receptors and may produce stronger cognitive effects in schizophrenia.
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PMID:Cognitive effects of adjunctive 24-weeks Rivastigmine treatment to antipsychotics in schizophrenia: a randomized, placebo-controlled, double-blind investigation. 1679 63