Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0040822 (tremor)
 18,428 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The effect of comedication with fluvoxamine on the plasma concentrations of the enantiomers of citalopram and its metabolites in dextromethorphan/mephenytoin phenotyped patients pretreated with citalopram (CIT) was studied: seven female patients (45.1 +/- 13.9 years) suffering from a major depressive episode [ICD-10: F32.2 (n = 3 patients), F33.2 (n = 2), F32.10 (n = 1) or F32.11 (n = 1)], who were non-responders to a 3-week treatment with 40 mg/day CIT (From day-21 to day 0) (day 0: MADRS score > or = 12), were co-medicated for another 3 weeks with fluvoxamine (50 mg/day from day 1-7, 100 mg/day from day 14-21). All patients were extensive metabolizers of mephenytoin (CYP2C19) and dextromethorphan (CYP2D6), except one patient, who had a genetic deficiency of CYP2D6. There was a significant increase of the plasma concentrations of S- and R-citalopram from day 0 (27 +/- 14 micrograms/l and 55 +/- 23 micrograms/l, respectively) to day 21 (83 +/- 38 micrograms/l and 98 +/- 44 micrograms/l, respectively), after addition of fluvoxamine (P < 0.02, for each comparison), and the mean ratio S/R-citalopram increased from 0.48 to 0.84. S-Citalopram inhibits more potently 5-HT uptake than R-citalopram: therefore, fluvoxamine increases the pharmacologically more active S-citalopram with some stereoselectivity. According to a previous in vitro study, this pharmacokinetic interaction occurs on the level of CYP2C19, but also of CYP2D6 and CYP3A4 which, in contrast to CYP1A2, contribute to the N-demethylation of citalopram and which are stereoselectively inhibited by fluvoxamine. All but one patient showed clinical improvement by a decrease of the MADRS score by at least 50% and a final score < or = 13 (mean +/- SD: day 0:30.6 +/- 9.2; day 21:11.0 +/- 6.5). Some patients showed minor symptoms, such as nausea and tremor, but the combined treatment was generally well tolerated.
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PMID:Non-response to citalopram in depressive patients: pharmacokinetic and clinical consequences of a fluvoxamine augmentation. 898 13

Postural instability and gait disorders (PIGD) are the primary causes of disability in many but not all advanced Parkinson's disease (PD) patients. We have measured the concentrations of serotonin, 5-hydroxytryptophan (5-HTP), 5-hydroxy-3-indoleacetic acid (5-HIAA), and homovanillic acid (HVA) in samples of ventricular cerebrospinal fluid from ten PD patients with severe disability from PIGD and from ten PD patients with tremor and levodopa induced dyskinesia as their predominant motor dysfunction. The two groups were prospectively matched for duration of disease and age. No significant differences between the two groups were found in the concentration (mean +/- SD in ng/ml, PIGD dominant vs. tremor-dyskinesia dominant) of 5-HIAA (106 +/- 50 vs. 99 +/- 34) or HVA (1,068 +/- 595 vs. 881 +/- 469). Serotonin concentration was significantly lower (0.7 +/- 0.5 vs. 1.5 +/- 0.9) and 5-HTP concentration was substantially higher (684 +/- 1,054 vs. 6 +/- 5) in the patient group with PIGD as their predominant symptoms. Thus, the distinguishing feature of patients with severe PIGD appears to be a derangement in indoleamine metabolism at the reaction step catalyzed by aromatic amino acid decarboxylase (AADC). These findings suggest that aggravation of PIGD in advanced Parkinson's may be related in part to impaired serotonergic transmission secondary to inhibition or down regulation of AADC.
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PMID:Concentrations of indoleamine metabolic intermediates in the ventricular cerebrospinal fluid of advanced Parkinson's patients with severe postural instability and gait disorders. 929 77

This is a first report on the investigation of the antidepressant activity of MCI-225 (4-(2-fluorophenyl)-6-methyl-2-(1-piperazinyl)thieno[2,3-d]pyrimidine monohydrate hydrochloride, CAS 99487-26-0) in comparison with maprotiline (CAS 10347-81-6), desipramine (CAS 58-28-6), imipramine (CAS 113-52-0) and trazodone (CAS 25332-39-2). MCI-225 inhibited the synaptosomal uptake of noradrenaline (NA, Ki = 35.0 nmol/l), serotonin (5-HT, Ki = 491 nmol/l), and dopamine (Ki = 14,800 nmol/l), although it did not inhibit MAO-A and MAO-B activities. MCI-225 showed high affinity only for the 5-HT3 receptor (Ki = 81.0 nmol/l) among all receptors tested including M1, M2, alpha 1, and H1 receptors. The inhibition of the von Bezold-Jarisch reflex by MCI-225 (ID50 = 22.2 mg/kg, p.o.) suggests its antagonistic action on the 5-HT3 receptor. MCI-225 dose-dependently reduced reserpine-induced hypothermia (0.3-10 mg/kg, p.o.) and potentiated yohimbine-induced lethality (3-100 mg/kg, p.o.) in mice. These effects of MCI-225 were as potent as desipramine and more potent than maprotiline, imipramine and trazodone. MCI-225 and desipramine did not change either 5-HTP-induced head movements or p-CA-induced hyperactivity in rats. In forced swimming tests in rats, the minimum effective doses of MCI-225, maprotiline, desipramine, and imipramine were 1, 30, 10 and 30 mg/kg, p.o., respectively, for 5-days administration. Only MCI-225 had shown its full activity with this short term treatment. MCI-225 (10 mg/kg, p.o.) decreased the REM sleep period without affecting slow-wave sleep or wakefulness in rats. Even at 100 mg/kg, p.o. MCI-225 and trazodone did not inhibit oxotremorine-induced tremor, lacrimation or salivation in mice in contrast with imipramine. These results suggest that MCI-225, which selectively inhibits NA uptake and antagonizes the 5-HT3 receptor, has potential as a new type of potent antidepressant.
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PMID:Pharmacological profile of the novel antidepressant 4-(2-fluorophenyl)-6-methyl-2-(1-piperazinyl)thieno-[2,3-d]pyrimidine monohydrate hydrochloride. 945 Jan 61

The excitatory effect of bradykinin (BK) and of low pH on nociceptors appears to partly depend on secondary release of prostaglandins from the surrounding tissue. Rat skin, in vitro, is introduced as a novel model to measure basal and stimulated release of PGE2 and, in future, other substances relevant to nociception, such as neuropeptides. Flaps of hairy skin (n=57) from the rat saphenous region of the hindpaw were subcutaneously excised and fixed on acrylic rods, the corium side exposed. The preparations were equilibrated in carbogen gassed "synthetic interstitial fluid" (SIF) for 30 minutes. The skin flaps were then immersed for 5 minutes each in 9 consecutive glass tubes, which were mounted in a shaking bath at 32 degrees C. Each tube was filled with 5 ml of gassed SIF, the third tube contained inflammatory mediator(s) dissolved in SIF or solutions of low pH. After passage of the skin flap, the eluates were deep frozen (-70 degrees C) and the PGE2 content measured, off-line, using an enzyme immuno-assay. As stimulants, BK at 10(-5) M (n=9) and 10(-6) M (n=4) and BK in equimolar combination with histamine (HA) and serotonin (5-HT; 10(-5) M: n=8, 10(-6) M: n=6, 10(-7) M: n=6) dose-dependently increased PGE2 release. Considering the total amount of PGE2 secreted the combination of inflammatory mediators caused a significantly greater release of PGE2 at 10(-5) and 10(-6) M (p<0.01, Kruskal-Wallis test) than BK stimulation alone. Racemic flurbiprofen caused a profound depression of basal and stimulated release. Solutions of high proton concentration are known to stimulate and sensitize nociceptors. However, phosphate buffered SIF at pH 6.1 and 6.4 caused a substantial and significant decrease of the PGE2 release, probably due to low-pH block of phospholipases. Thus, algogenic potency of mediators does not necessarily match their pro-inflammatory action.
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PMID:Stimulated prostaglandin E2 release from rat skin, in vitro. 962 3

The effects of intracerebroventricular injections of serotonin (5-HT) antibodies were studied for changes in 5-HT, dopamine (DA), their metabolites and norepinephrine (NE) as well as 5-HT mediated behavior in adult mice. While nociceptive thresholds (tail-flick latency) were inhibited in antibody treated animals, tremor response to 5-methoxy-N,N-dimethyl tryptamine administration was increased. 5-HT and DA in the nucleus raphe dorsalis (NRD), substantia nigra (SN), nucleus caudatus putamen (NCP) and in the substantia grisea centralis, and NE in the former two nuclei were significantly decreased in these animals. 5-Hydroxyindoleacetic acid was unaffected in all nuclei except NRD, where it was inhibited. Homovanillic acid and 3,4-dihydroxyphenylacetic acid were inhibited in all nuclei except in NCP. The brunt of insult was more evident in NRD and SN where all neurotransmitters were inhibited for a longer period. 5-HT turnover was increased in all the nuclei, however only SN showed increased DA turnover. It may be assumed that the observed neurochemical and behavioral changes were the consequence of the antibodies binding to 5-HT, which in turn influenced the anatomically and functionally connected neurotransmitters. While the study contributes to the existing understanding of central neurotransmitter control on behavior, it fails to delineate the underlying mechanism. The possibility of developing a useful, drug-free 5-HT deficient animal model for studying clinical disorders, as well as for solving some of the basic questions related to the physiological functions of 5-HT in adult animals are envisaged from the study.
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PMID:Behavioral and neurochemical alterations following intracerebroventricular administration of anti-serotonin antibodies in adult Balb/c mice. 970 92

Effects of MKC-242 (5-[3-[((2S)-1,4-benzodioxan-2-ylmethyl)amino]propoxy]-1,3-b enzodioxole HC1), a novel 5-HT1A-receptor agonist, and reference compounds on wrap restraint stress-induced defecation were evaluated in rats. Wrapping restraint stress increased defecation in rats. The increase was attenuated by putative 5-HT1A-receptor agonists, MKC-242 and 8-hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT). The suppressive effect of MKC-242 on wrap stress-induced defecation was antagonized by prior administration of a 5-HT1A-receptor antagonist, WAY100135. MKC-242 did not affect spontaneous defecation and 5-HT-induced defecation. Diazepam and amitriptyline also significantly reduced the stress-induced defecation. However, amitriptyline showed a potent anti-cholinergic effect in the oxotremorine-induced tremor test and reduced spontaneous defecation. In contrast to MKC-242 and 8-OH-DPAT, buspirone and tandospirone tended to suppress the increase at high doses. A major metabolite of buspirone and tandospirone, 1-(2-pyrimidinyl)piperazine, antagonized the suppressive effect of MKC-242. These findings suggest that stimulation of 5-HT1A receptors reduces stress-induced defecation but not spontaneous and 5-HT-induced defecation and that MKC-242 may be useful for the treatment of irritable bowel syndrome.
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PMID:Reduction of wrap restraint stress-induced defecation by MKC-242, a novel benzodioxan derivative, via 5-HT1A-receptor agonist action in rats. 971 68

It has been reported that dehydroepiandrosterone (DHEA) or dehydroepiandrosterone sulfate (DHEA-S) is associated with affective disorders and that pathology of affective disorders are related with dysfunction of serotonin(5-HT)-2A receptor-mediated responses. In this study, we investigated the effect of DHEA on (+/-)-1-(2,5-dimethoxy-4-iodophenyl)-2 aminopropane (DOI), 5-HT-2A receptor agonist, -induced wet dog shaking behavior (WDS) in rats. Acute treatment with DHEA inhibited the DOI-induced WDSs dose dependently. This inhibition was recovered by opioid receptor antagonist, naltrexone. 5-HT-2A receptor-mediated WDSs were desensitized after chronic treatment with DOI, however chronic treatment with DHEA had no effect on this desensitization. Chronic treatment with DHEA had no facilitating effect of chronic dexamethasone treatment on DOI-induced WDSs. These findings may lead the possibility that DHEA has the inhibitory effect of 5-HT-2A mediated signaling pathway via non-genomic action.
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PMID:Effect of acute and chronic administration of dehydroepiandrosterone on (+/-)-1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane-induced wet dog shaking behavior in rats. 1019 32

Iodine-123-beta-CIT (2 beta-carbomethoxy-3 beta-(4-iodophenyl)tropane) binds with high affinity to dopamine (DA) and serotonin (5-HT) transporters. This study examined the correlation of single-photon emission computed tomographic (SPECT) measures of [123I]beta-CIT binding to DA and 5-HT transporters with symptom severity in Parkinson's disease (PD). Forty-six L-dopa-responsive PD patients (Hoehn-Yahr stage 1-3) had SPECT scans at 20-24 h after injection of [123I]beta-CIT. Specific to nondisplaceable uptake ratios (designated V"3) were calculated in the striatum and hypothalamic/midbrain region, where the binding of [123I]beta-CIT is associated primarily with DA and 5-HT transporters, respectively. Striatal V"3 was significantly correlated with Hoehn-Yahr stage and total, motor and activities of daily living scores of Unified Parkinson's Disease Rating Scale (UPDRS). There was a significant correlation between the sum of lateralizing motor UPDRS subscores (tremor, rigidity, bradykinesia) calculated for each side of limbs and V"3 values in the contralateral striatum. No significant correlation was found between striatal V"3 and UPDRS rating of mentation, behavior, and mood. Hypothalamic/midbrain V"3 was not significantly correlated with either Hoehn-Yahr stage or UPDRS scores including both motor and nonmotor measures. The significant correlation of SPECT measures of striatal [123I]beta-CIT binding with motor severity suggests that [123I]beta-CIT binding to striatal DA transporters can serve as an in vivo indicator of disease severity in PD, with potential utility in the serial monitoring of disease progression.
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PMID:SPECT measurement of iodine-123-beta-CIT binding to dopamine and serotonin transporters in Parkinson's disease: correlation with symptom severity. 1031 33

Serotonin reuptake inhibitors, used as antidepressants, may cause hyponatremia due to a syndrome of inappropriate antidiuretic hormone, specially in elders. Thirty cases with such complication have been reported in the last six years. We report a 76 years old female with a hypertensive cardiopathy and paroxysmal atrial fibrillation treated with amlodipine and sotalol. Five days after starting fluoxetine, the patient presented with a confusional state, gait instability and tremor. Laboratory assessment disclosed a plasma sodium of 115 meq/L. Fluoxetine was discontinued and fluids were restricted. The clinical condition of the patient improved and hyponatremia abated. Hyponatremia must be born in mind as a potential side effect of serotonin reuptake inhibitors.
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PMID:[Severe hyponatremia during treatment with fluoxetine]. 1043 20

We investigated the effects of various serotoninergic drugs and serotonin (5-HT) depletion on physostigmine-induced visible tremor in rats. Physostigmine (0.25-1.5 mg/kg) caused dose-dependent tremor, initiated at 3-5 min (latency decreases as dose increases) and lasted for 30-35 min. Serotonin agonists, 8-hydroxy-2-(di-n-propylamino) tetralin (2.5 mg/kg) and buspirone (5 mg/kg) augmented the tremor response caused by physostigmine. The 5-HT(1)/5-HT(2) receptor antagonist, metergoline (1 mg/kg), and 5-HT(2) blocker, cyproheptadine (10 mg/kg) significantly decreased the duration (40%) as well as intensity (45-50%) of physostigmine-tremor. The 5-HT(2a)/5-HT(2c) antagonist ritanserin (5 mg/kg) significantly reduced the duration (60%) without affecting the intensity of the tremor. In 5-HT depleted rats (p-chlorophenylalanine; 300 mg/kg, for 3 days), physostigmine failed to produce tremor. Interestingly, in these animals, administration of a non-specific 5-HT agonist, 5-methoxy-N,N-dimethyl tryptamine, caused high intensity tremor. These results suggest that presence of 5-HT at the pre-synaptic terminals is needed for the tremor response by physostigmine and the response is greatly mediated via post-synaptic 5-HT receptors. The overall data indicated a direct involvement of central 5-HT system in the cholinergic tremor induced by physostigmine.
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PMID:Effects of serotoninergic drugs on tremor induced by physostigmine in rats. 1076 88


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