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

It is difficult to choose among the many drugs advocated for treating anxiety symptoms. The barbiturates were the most commonly used antianxiety agents until recently but are being superseded by the benzodiazepines. The latter are more effective than the barbiturates as shown in comparative clinical trials, they are safer in overdosage (deliberate or accidental), and they are somewhat less likely to induce dependence. The barbiturates have the additional drawback of interfering with the action of other drugs by inducing liver microsomal (oxidising) drug metabolising enzymes. The major tranquilisers (neuroleptics or antipsychotics) are often of value in low dosage in patients with a previous history of dependence on alcohol, the barbiturates or the benzodiazepines. Tricyclic antidepressants are the treatment of choice in anxious and depressed patients and monoamine oxidase inhibitors may be helpful in phobic patients. The beta-adrenoreceptor blocking agents such as propranolol often ameliorate somatic symptoms such as palpitations and tremor. In the treatment of anxious patients it is important to remove causes for anxiety and to limit any course of drug treatment to a finite period. Both dosage level and dosage interval should be flexible. Benzodiazepines remain the drug treatment of choice.
 ...
PMID:Antianxiety drugs: clinical pharmacology and therapeutic use. 1 Jan 53

Previous studies have established that a complex behavioral syndrome--consisting of tremor, rigidity, hindlimb abduction. Straub tail, lateral head weaving and reciprocal forepaw treading--is a specific reflection of the activity of central serotonin receptors. This syndrome was utilized in the present study to test for supersensitivity in the central serotonergic system. Specific destruction of central serotonin nerve terminals by intraventricular injection of 5,7-dihydroxytryptamine (5,7-DHT, 50 mug) in adult male rats pretreated with a catecholamine uptake blocking agent resulted in marked supersensitivity to serotonin precursors and agonists. The greatest degree of supersensitivity was observed in response to L-5-hydroxytryptophan, for which the ED50 for elicitation of the syndrome was 20% of the value for control rats. A lesser degree of supersensitivity was seen in response to L-tryptophan (following monoamine oxidase inhibition) and the direct-acting serotonin agonist, 5-methoxy-N,N-dimethyltryptamine, for which the ED50 was approximately 50% of the control value in both cases. Supersensitivity begins to develop within 24 hours and is relatively complete by 96 hours after 5,7-DHT. A marked subsensitivity to the serotonin releasing agent, fenfluramine, was found in 5,7-DHT-treated rats. In contrast to the marked supersensitivity to serotonin precursors and agonists which occurs following 5,7-DHT, chronic administration of a serotonin synthesis inhibitor, p-chlorophenylalanine (400 mg/kg every 3 days for a total of 24 days), did not produce supersensitivity to L-5-hydroxytryptophan or 5-methoxy-N,N-dimethyltryptamine. Possible pre- and postsynaptic mechanisms for the development of supersensitivity are discussed.
 ...
PMID:Behavioral evidence for supersensitivity following destruction of central serotonergic nerve terminals by 5,7-dihydroxytryptamine. 13 25

The practical value of measuring plasma concentrations is to optimize treatment in order to attain the best balance in each particular patient between wanted clinical therapeutic effects and unwanted adverse and side-effects. This increase in treatment efficacy can be concurrent--that is, the treatment is monitored and the dosage changed as necessary--or predictive, where the results of a test dose can be used to calculate the appropriate dosage. Wanted effects include: (1) the attainment of adequate drug concentrations for the minimum period of time necessary, as in the use of antibiotics; (2) the suppression of symptoms, as in the use of the benzodiazepines in anxiety states; (3) the use of drugs to improve function, e.g. levodopa in Parkinsonism; (4) drugs are used to prevent episodes of illness; and (5) complex suppression of symptoms, as with the antidepressives and antipsychotics. The biological alternatives to plasma level monitoring depend on establishing an empirical relationship between the putative monitor and the clinical response. Such measures avoid the problem of estimation of drug concentration at the receptor. Examples include monoamine oxidase activity in platelets, the uptake of amines into platelets, neuroendocrine measures such as prolactin concentrations, the electroencephalogram, and peripheral measures such as pulse rate, pupil size and tremor.
 ...
PMID:Drug concentrations in neuropsychiatry: alternative approaches. 26 86

Intraventricular administration of serotonin to rats causes 'wet-dog' shakes, a sign of morphine withdrawal. The frequency of shakes is dose-dependent. Shaking is potentiated by pretreatment with an inhibitor of monoamine oxidase or with 5,7-dihydroxytryptamine, and is depressed by morphine or serotonin receptor blockers. Depression of serotonin-induced shaking by morphine is reversed rapidly by naloxone. However, naloxone did not reverse the inhibition of 'wet-dog' shakes caused by serotonin receptor blockers.
 ...
PMID:Effect of morphine on 'wet-dog' shakes caused by cerebroventricular injection of serotonin. 57 8

Pharmacological stimulation of central serotonin (5-HT) receptors causes a behavioral syndrome characterized by simultaneous side-to-side head weaving or head tremor, forepaw padding and splayed hindlimbs. This syndrome has been proposed and used as a model for 5-HT receptor activity. Questions have been raised about the possible involvement of catecholamines. This study was designed to differentiate behavioral signs contributed by 5-HT from those that might be due to catecholamines. Depletion of catecholamines by alpha-methyl-p-tyrosine, or depletion of 5-HT by either p-chlorophenylalanine or 5,7-dihydroxytryptamine, did not prevent the syndrome caused by 5-methoxy-N,N-dimethyltryptamine, a 5-HT receptor agonist. Pretreatment with methysergide, but not phenoxybenzamine or pimozide, prevented the syndrome caused by 5-methoxy-N,N-dimethyltryptamine. Conversely, 5-HT depletion prevented the syndrome caused by monoamine oxidase inhibitor and levodopa; behavioral response was restored in p-chlorophenylalanine-pretreated rats by 5-hydroxytryptophan. Methysergide prevented the syndrome caused by monoamine oxidase inhibitor and levodopa, but phenoxybenzamine or pimozide did not. Intraventricular 5-HT or dopamine also caused the behavioral syndrome after monoamine oxidase inhibition. p-Chlorophenylalanine pretreatment prevented the syndrome caused by dopamine, but did not prevent the syndrome caused by 5-HT. Our results suggest that systemic levodopa or intraventricular dopamine produces the behavioral signs through 5-HT mechanisms; endogenous catecholamine mechanisms are not involved directly in either the cause or expression of the behavioral syndrome.
 ...
PMID:Specificity of a rat behavioral model for serotonin receptor activation. 68 17

Hindlimb tremor was produced in chronic cats by intracaudate microinjection of the monoamine oxidase (MAO) inhibitors tranylcypromine and harmaline throughout a range of doses (150-385 mug). Pargyline, however, was non-tremorgenic within the same range, suggesting that interference with MAO is not sufficient in itself to elicit tremor. Tranylcypromine tremors differed from those of harmaline by exhibiting a slower onset, longer duration and susceptibility to antagonism by hemicholinium. In contrast, ongoing cholinergic tremors following intracaudate physostigmine were variably suppressed by all three MAO inhibitors at comparable dose levels (175-200 mug); pargyline produced the most complete suppression. These results indicate that MAO inhibitors can modify tremor activities in a differential manner dependent both on the functional state of the caudate nucleus and on the ability of cartain MAO inhibitors to exert other local actions.
 ...
PMID:Contrasting local effects of MAO inhibitors on caudate tremor activities. 112 76

1-Tryptophan was administered to rats pretreated with selective inhibitors of the A and B forms of MAO deprenyl, a selective inhibitor of MAO-B, produced minor changes in behaviour and in the concentrations of apparent 5-HT and 5-HAA in brain. High doses of clorgyline, a selective inhibitor MAO-A, produced a characteristic stereotyped syndrome of hypermotility and tremor as well as an increase in apparent 5-HT and a decrease in apparent 5-HIAA in brain. Small doses of deprenyl and clorgyline in combination, but not singly, produced maximal effects on behaviour as well as on the concentrations of apparent 5-HT and 5-HIAA in brain. Maximum behavioural and biors before the other. It is concluded that the syndrome may be dependent on the formation of an N-substituted derivative of 5-HT which is at least partly deaminated by MAO-B. Alternatively, the syndrome may be dependent on a sufficiently high concentration of 5-HT in a special compartment where it is partly deaminated by MAO-B.
 ...
PMID:The inhibition of A and B forms of MAO in the production of a characteristic behabioural syndrome in rats after 1-tryptophan loading. 117 89

A review of the clinical efficacy of four structurally distinct antidepressant drugs is presented. Their antidepressant activity can be rationalised within current pharmacological hypotheses of drug action, despite markedly different effects on "in vitro" testing. Fluoxetine, a specific serotonin re-uptake inhibitor, has proven safe, effective treatment for depressive illness and may have a role to play in the treatment of obsessive-compulsive disorder and panic attacks. While it has few of the anticholinergic side effects of the tricyclic antidepressants, nausea, tremor, headache, weight loss, nervousness and sweating are side effects most frequently reported. Minaprine, a compound with weak MAO inhibiting properties and effects on serotonergic receptors, has clinical efficacy in the treatment of depression based on several comparative studies. It is claimed that minaprine lacks anticholinergic and sedative properties. Moclobemide, a specific, reversible inhibitor of MAO-A, has been extensively evaluated in depressive illness. The major advantage of this agent over other irreversible, non-specific MAO inhibitors, is the significant attenuation of the so-called "cheese effect" with doses of tyramine likely to be encountered in foodstuffs. Rolipram, a phosphodiesterase inhibitor, represents a new approach to antidepressant treatment. Limited clinical data suggest that the drug may be an effective antidepressant with few side effects. The place of these agents in therapy is yet to be established.
 ...
PMID:New pharmacological approaches to the management of depression: from theory to clinical practice. 158 Aug 88

1. 2-Propyl-1-aminopentane and 2-[(2-propyl)pentylamino]acetamide are deaminated by rat liver monoamine oxidase (MAO) and aorta semicarbazide-sensitive amine oxidase (SSAO). 2. The deaminated product, 2-propylpentaldehyde, is further converted to valproic acid in vitro as well as in vivo. 3. The anticonvulsant action of these two compounds could not be substantiated, because both drugs at relatively low doses caused distinct tremor in mice and rats. 4. Both compounds also potentiate the convulsant effect induced by mercaptopropionic acid.
 ...
PMID:Deamination of 2-propyl-1-aminopentane and 2-[(2-propyl)pentylamino] acetamide by amine oxidases: formation of valproic acid. 190 6

The authors describe two series of patients: 12 treated simultaneously with fluoxetine and a monoamine oxidase inhibitor and 6 patients started on treatment with an MAOI 10 days or more after stopping fluoxetine treatment. All patients had extremely refractory depression and were treated in open fashion before general knowledge was obtained of the side effects that may accompany the fluoxetine-MAOI combination. During the fluoxetine-MAOI trial, most patients continued to receive other psychotropic combinations that had been partially helpful. The use of fluoxetine and an MAOI, either together or in close succession, was accompanied by a very high incidence of adverse effects, especially the "serotonergic syndrome." This syndrome was characterized by mental status changes, such as hypomania and confusion, and physical symptoms, such as myoclonus, hypertension, tremor, and diarrhea. Because of the high incidence of side effects and the lack of definite efficacy, the concurrent use of fluoxetine and MAOIs should generally be avoided. The long half-lives of fluoxetine and norfluoxetine, as well as the prolonged metabolic effects of MAOIs, may also dispose patients to an interaction if one of the drugs is started soon after stopping the other.
 ...
PMID:Adverse consequences of fluoxetine-MAOI combination therapy. 199 42


1 2 3 4 5 6 7 8 Next >>