Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0004134 (ataxia)
 15,886 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Phencyclidine (PCP), a drug inducing schizophrenia-like symptoms in humans, is reported to be a non-competitive antagonist at the N-methyl-D-aspartate (NMDA) subtype of excitatory amino acid receptors. In rats, PCP produces three dose-dependent stages of EEG patterns: 1) increase of cortical desynchronization duration; 2) increase of the amplitude of the high-frequency (20-30 Hz) low-voltage (30-50 microV) cortical background activity; 3) appearance of cortical slow (2-3 Hz) wave-sharp wave complexes. These EEG changes are accompanied by stimulatory-depressive effects such as stereotypy (circling, head weaving) and ataxia. In the present study, the EEG and behavioural effects induced by systemic administration of the NMDA antagonists dizocilpine (MK 801), dextromethorphan (DM), [(+)-alpha-(4-chlorophenyl)-4- [(phenyl)methyl-1-piperidine ethanol] (SL 82.0715), (+)3-(2-carboxypiperazin-4-yl)-propyl-1-phosphonic acid (CPP), cis-4-phosphonomethyl-2-piperidine-carboxylic acid (CGS 19755) have been compared to those of PCP in rats. The rank of potency for inducing PCP-like EEG stages 1-3 was as follows: MK 801 > PCP > CGS 19755 > CPP. These drugs also induced PCP-like behavioural effects. On the contrary, DM and SL 82.0715, administered up to the dose of 100 mg/kg IP, failed to induce PCP-like behavioural effects and elicited only the stage 1 of PCP-like EEG. These results strongly suggest the involvement of NMDA neurotransmission in the behavioral and EEG effects of PCP.
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PMID:Different capability of N-methyl-D-aspartate antagonists to elicit EEG and behavioural phencyclidine-like effects in rats. 136 27

Three piperidine alkaloid containing plants, Conium maculatum (poison-hemlock), Nicotiana glauca (tree tobacco) and Lupinus formosus (lunara lupine), induced multiple congenital contractures (MCC) and palatoschisis in goat kids when their dams were gavaged with the plant during gestation days 30-60. The skeletal abnormalities included fixed extension or flexure of the carpal, tarsal, and fetlock joints, scoliosis, lordosis, torticollis and rib cage abnormalities. Clinical signs of toxicity included those reported in sheep, cattle and pigs--ataxia, incoordination, muscular weakness, prostration and death. One quinolizidine alkaloid containing plant, Lupinus caudatus (tailcup lupine), on the other hand, which is also known to cause MCC in cows, caused only slight signs of toxicity in pregnant goats and no teratogenic effects in their offspring.
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PMID:Congenital skeletal malformations and cleft palate induced in goats by ingestion of Lupinus, Conium and Nicotiana species. 208 36

Tonic-clonic convulsions of mutant quaking mice were antagonized by the intracerebroventricular injection of N-methyl-D-aspartate receptor antagonists. The competitive antagonists, CPP (3-((+/-)-2-carboxypiperazin-4-yl)-propyl-1-phosphonic acid) and CGS 19755 (cis-4-(phosphonomethyl)-2-piperidine carboxylic acid), exerted a partial anticonvulsant action, with ED50S of 0.115 and 0.076 nmol, respectively. The non-competitive antagonists, TCP (1-(1-(2-thienyl)cyclohexyl)piperidine) and MK-801 [+)-5-methyl-10,11-dihydro-5H-dibenzo(a,d)cyclohepten-5,10-imine), provided full protection, with ED50s of 4.49 and 2.67 nmol, respectively. The competitive antagonists elicited a marked ataxia whereas the non-competitive antagonists did not have side-effects. These results might reflect the involvement of glutamatergic neurotransmission in the convulsions of the quaking mutants.
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PMID:Anticonvulsant effects of antagonists of the N-methyl-D-aspartate receptor complex in a genetic model of epilepsy: the quaking mouse. 215 55

The competitive excitatory amino acid antagonist cis-4-phosphonomethyl-2-piperidine-carboxylic acid (CGS 19755) increased the latency for monkeys to remove their tails from warm water (analgesia); larger doses produced ataxia, loss of righting, salivation, and eliminated reactivity to stimulation (anesthesia). CGS 19755 decreased tidal volume and had little effect on frequency of respiration. Although longer lasting, the effects of CGS 19755 were similar to the effects of ketamine, suggesting these effects result from actions at the NMDA receptor complex.
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PMID:Analgesic, anesthetic, and respiratory effects of the competitive N-methyl-D-aspartate (NMDA) antagonist CGS 19755 in rhesus monkeys. 225 91

A series of 1,2,3,4-tetrahydroisoquinolines, tetrahydrothieno[2,3-c]pyridines, and related compounds were evaluated for their ability to inhibit binding of [3H]-1-[1-(2-thienyl)piperidine and [3H]-N-allylnormetazocine to phencyclidine (PCP) and sigma receptors, respectively. A representative series of compounds was evaluated in behavioral assays to determine the ability of the compounds to induce PCP-like stereotyped behavior and ataxia. All of the compounds caused stereotyped behavior and ataxia, indicating their agonist actions at the PCP site.
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PMID:Phencyclidine-like effects of tetrahydroisoquinolines and related compounds. 254 55

Thirty-seven arylcyclohexylamines including phencyclidine (PCP) and derivatives, N[1-(2-thienyl)cyclohexyl]piperidine (TCP) and derivatives and N-[1-(2-benzo(b)thiophenyl)cyclohexyl]piperidine (BTCP) were assessed for their ability to inhibit [3H]PCP binding and [3H]dopamine ([3H]DA) synaptosomal uptake. Their pharmacological property (ataxia) was measured by means of the rotarod test. A very good correlation was observed between the inhibition of [3H]PCP binding and the [3H]DA uptake only for arylcyclohexylamines bearing an unmodified phenyl group. Conversely the comparison between the inhibition of [3H]PCP binding and the activity in the rotarod test shows a good correlation with arylcyclohexylamines having any aromatic group (phenyl, substituted phenyl and thienyl rings). This study outlined a new compound (BTCP) without ataxic effect, which is one of the more potent inhibitors of the [3H]DA uptake (IC50 = 8 nM) and which seems very specific since it has a low affinity for [3H]PCP receptors (IC50 = 6 microM). These data show that the aromatic group of the compounds leads to molecules that bind differently to the PCP receptor and to the DA uptake complex. They also suggest that the behavioral properties of arylcyclohexylamines revealed by the rotarod test occur essentially as a result of an interaction with the sites labeled with [3H]PCP and that TCP is more selective than PCP itself in this recognition.
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PMID:Role of the aromatic group in the inhibition of phencyclidine binding and dopamine uptake by PCP analogs. 254 5

The effects of the subchronic administration of (+)-5-methyl-10,11-dihydro-5H-dibenzo[a,d]-cyclohepten-5,10-imine (MK-801) (0.5 mg/kg twice daily, 7 days) on N-methyl-D-aspartate, phencyclidine and sigma binding sites, behaviour and catecholamine turnover were investigated in the rat. Overt behaviours induced by MK-801 on day 7 were significantly altered relative to day 1 with subchronically treated rats not showing head weaving, goss ataxia or loss of hindlimb control: locomotion and sniffing were largely unaffected. The mean intensities of behaviour were 1.8 and 5.4 for days 7 and 1, respectively. Behavioural tolerance was accompanied by a significant reduction in the density of cortical N-methyl-D-aspartate receptors as measured by [3H]D-2-amino-5-phosphonopentanoic acid binding, while affinity was unchanged: the density of binding sites was 3.52 and 1.88 pmol/mg protein for saline- and MK-801-treated rats, respectively. The N-methyl-D-aspartate ion channel as measured by the binding of [3H]N-(1-[2-thienyl]cyclohexyl)piperidine was not affected by the schedule of MK-801. Additionally, changes were not observed to N-methyl-D-aspartate- or glycine-stimulated [3H]N-(1-[2-thienyl]cyclohexyl)piperidine binding or to sigma binding. Catecholamine turnover was unaltered in the nucleus accumbens septi after the schedule of MK-801. Our results demonstrate that the subchronic administration of MK-801 produces behavioural tolerance and down-regulation of N-methyl-D-aspartate binding sites and suggest differential regulation of the domains of the N-methyl-D-aspartate receptor-ionophore complex.
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PMID:Subchronic administration of MK-801 in the rat decreases cortical binding of [3H]D-AP5, suggesting down-regulation of the cortical N-methyl-D-aspartate receptors. 256 2

The pharmacology and structure-activity relationship of phencyclidine (PCP)-like drugs (phencyclinoids) were studied using electroencephalographic (EEG), behavioral and receptor binding techniques. The effects of PCP, 1-phenylcyclohexylamine HCl, N-methyl-1-phenycyclohexylamine HCl, N-ethyl-1-phenylcyclohexylamine HCl, N-(s-butyl)-1-phenylcyclohexylamine HCL, 1-(1-phenylcyclo-hexyl)-pyrrolidine HCl, 1-[1-(2-thienyl)cyclohexyl] piperidine HCl, 1-[1-(2-thienyl)cyclohexyl]-pyrrolidine HCl, ketamine and (+/-)-SKF 10047 were evaluated on the direct EEG and EEG spectra after acute i.v. injections (0.1-17.8 mg/kg). Similarities and differences were noted in the EEG dose-response curves. At lower doses of PCP and its analogs, low-amplitude theta waves predominated; however, at higher doses, high-amplitude, lower-frequency waves predominated. Qualitatively, the N-piperidine derivatives were similar to PCP and differed primarily in potency. The benzomorphan (+/-)-SKF 10047 produced only theta activity at doses up to 12.8 mg/kg. These EEG effects occurred in conjunction with overt behaviors including locomotion, stereotypy and ataxia, concurrently assessed via observer-based rating scales. A strong correlation (r = 0.98) was obtained between the EEG and behavioral effects and the IC50 values from [3H]PCP displacement experiments using crude rat brain homogenates.
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PMID:Electroencephalographic, behavioral and receptor binding correlates of phencyclinoids in the rat. 284 54

Metaphit, which acylates phencyclidine (PCP) receptors in vitro, was shown to acylate PCP receptors and antagonize the behavioral and electrophysiological effects of PCP in vivo. Metaphit (2 mumol/rat) administered i.c.v. produced PCP-like stereotyped behavior and ataxia in 10 to 20% of rats. At a lower dose, Metaphit (1 mumol/rat) antagonized the ability of PCP to induce stereotyped behavior and ataxia for 3 and 4 days, respectively. The Metaphit-induced antagonism of PCP induction of stereotyped behavior and ataxia was dose-dependent and specific as Metaphit did not antagonize induction of stereotyped behavior by amphetamine. Further evidence for a specific PCP receptor mechanism was the finding that PCP pretreatment blocked the effects of subsequent Metaphit administration. Metaphit also antagonized PCP-induction of stereotyped behavior, but not ataxia, after i.v. administration. Doses of Metaphit that produced long-term antagonism of the behavioral effects of PCP also produced a significant decrease in the maximum binding, but not Kd, of the binding of the PCP analog, [3H]-1-(2-thienyl)cyclohexyl]piperidine, in Metaphit-pretreated rats. The binding of [3H]etorphine and [3H]spiroperidol was not altered significantly by pretreating rats with Metaphit. (-)-Cyclazocine and (+)-SKF 10,047 induced stereotyped behavior and ataxia that was not antagonized by Metaphit-pretreatment. In electrophysiological experiments, Metaphit, like PCP, initially depressed the firing of caudate neurons as does PCP, but then irreversibly inhibited PCP-induced depression of caudate neurons. These results suggest that metaphit antagonized the effects of PCP by selectively acylating PCP receptors and that (-)-cyclazocine- and (+)-SKF 10,047-induced behavioral effects are not mediated primarily by PCP receptors.
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PMID:Metaphit, an acylating ligand for phencyclidine receptors: characterization of in vivo actions in the rat. 301 19

Brown oxidation of cis-bicyclo[3.1.0]hexan-3-ol afforded bicyclo[3.1.0]hexan-3-one in 98% yield. Treatment of this ketone with either phenyllithium or phenylamagnesium bromide in ether at room temperature followed by solvolysis of the resulting alcohol in a mixture of trifluoroacetic acid, sodium azide, and chloroform gave a mixture of cis- and trans-3-azido-3-phenylbicyclo[3.1.0]hexanes. LAH reduction of this crude mixture of azides afforded a 1:3.5 mixture of cis- and trans-3-phenyl-3-bicyclo[3.1.0]hexylamine, respectively, in 51% overall yield from the alcohol. Separation of the mixture of amines by column chromatography followed by cyclization of each by heating at 60 degrees C in DMF solution with 1 equiv of 1,5-dibromopentane furnished the two conformationally restrained analogues of phencyclidine (PCP), cis- and trans-3-phenyl-3-piperidinylbicyclo[3.1.0]hexane (1 and 2, respectively), in high yield. Configurations were assigned on the basis of an X-ray crystallographic analysis of the cis isomer (1). Bond lengths and angles are similar to those found in PCP and its derivatives. Binding to PCP receptors and sigma sites as well as behavioral effects of 1 and 2 in rats was determined relative to PCP. In displacement of specifically bound [3H]TCP (1-[1-(2-thienyl)cyclohexyl]piperidine) from PCP receptors, 1 and 2 were nearly equipotent and about one-seventh as potent as PCP. These compounds were about one-fifth as potent as PCP in displacing [3H]-(+)-SKF 10,047 from its binding site. Calculation of the ED50 values of 1 and 2 for stereotyped behavior and ataxia indicated that they were about equipotent, and 2-3-fold less active than PCP.
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PMID:Synthesis, configuration, and evaluation of two conformationally restrained analogues of phencyclidine. 339 94


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