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Query: UMLS:C0040822 (tremor)
 18,428 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Duerre, John A. (University of North Dakota, Grand Forks), and Patrick J. Buckley. Pigment production from tryptophan by an Achromobacter species. J. Bacteriol. 90:1686-1691. 1965.-A microorganism was isolated from the soil near the University of North Dakota. Biochemical and morphological characteristics indicated that this organism would best be classified as a member of the family Achromobacteraceae, genus Achromobacter, species unknown. The organism produced a red pigment when grown in a medium containing yeast extract and tryptophan. The pH optimum for pigment production was about 8.0 and the optimal temperature was 25 C. During a study of the nutritional requirements for growth and pigment production, it was found that the organism would grow and produce pigment in a medium containing tryptophan and nucleosides, but the rate of both growth and pigment formation in this medium was slower than that observed with tryptophan and yeast extract. The organism grew well in the presence of acid-hydrolyzed casein and nucleosides without producing pigment, indicating that the pigment is not necessary for growth. Resting-cell experiments definitely established tryptophan as the sole exogenous requirement for pigment production. The pigment was extracted from yeast extract-tryptophan medium with chloroform. Thin layer chromatographic analysis of the crude pigment extracted from this medium revealed the presence of two other pigments in addition to the major red pigment. One of these was a highly fluorescent orange pigment and the other a pink pigment. Only the red pigment was produced by resting cells in the presence of tryptophan alone. This pigment served as an electron acceptor when coupled with formic dehydrogenase, indicating its possible function as an oxidation-reduction pigment. The oxidized pigment had absorption peaks at 506 and 304 mmu. The peak at 506 mmu disappeared upon reduction with sodium sulfite. Shaking the reduced pigment in air proved to be an unsatisfactory method for returning the reduced pigment to the oxidized, colored state.
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PMID:Pigment production from tryptophan by an Achromobacter species. 585 90

The inferior olive of the cat has, with fluorescence histochemistry, been shown to receive a rich serotoninergic innervation. The distribution of this innervation agrees with the topography of spinal afferent termination as well as the olivo-cerebellar climbing fiber projection. This indicates that different olivary compartments are under different serotoninergic influence. The serotoninergic innervation of the dorsal accessory nucleus (DAO) of the inferior olive of the rat has been identified with electron microscopic radioautography after labelling with 3H-serotonin. The serotoninergic varicosities contain microcanaliculi, tubular-vesicular organelles and large granular vesicles. Few of the serotoninergic varicosities engage in typical synaptic junctions. However, non-junctional varicosities often display other ultrastructural indications of polarity and directed transmitted release. Electrophysiological results indicate that the harmaline-induced tremor, as well as the tremor component of the "serotonin-syndrome", depends on the serotoninergic innervation of the inferior olive. Thus, the sensitivity of different olivary compartments to the induction of rhythmic, synchronous activity by harmaline parallels the distribution of serotoninergic innervation. Neurotoxic destruction of the serotoninergic innervation leads to decreased sensitivity to harmaline. Further, the serotonin receptor agonist 5-methoxy-N,N-dimethyltryptamine, as well as monoamine oxidase inhibition + L-tryptophan loading, leads to rhythmic mass climbing fiber activity in the cerebellum and whole body tremor. A neuromodulatory effect of serotonin on the olivary action potential mechanisms is proposed.
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PMID:Morphological and functional studies on the serotoninergic innervation of the inferior olive. 616 26

Chronic administration of amphetamine to cats (twice daily, in doses increasing from 5 to 15 mg/kg over a 10-day period) elicited a number of behaviors e.g., limb flicking, abortive grooming, and excessive head shaking, which were originally proposed as an animal behavioral model for studying the actions of hallucinogens that depress central serotonergic neurotransmission. This drug treatment produced large decreases (approximately 50%) in central nervous system serotonin (5HT) and its major metabolite, 5-hydroxyindoleacetic acid, and even larger decreases (approximately 90%) in the levels of dopamine (DA) and norepinephrine. Administration of the 5HT precursors L-tryptophan (25 mg/kg i.p.) or L-5-hydroxytryptophan (12.5 mg/kg i.p.), a direct-acting 5HT agonist (quipazine, 1 mg/kg i.p.) or a monoamine oxidase inhibitor (tranylcypromine, 4 mg/kg i.p.) produced no significant changes in these behaviors in cats treated chronically with amphetamine. Administration of a 5HT reuptake blocker (fluoxetine, 5 mg/kg i.p.) produced a small, but significant, decrease in the frequency of occurrence of these behaviors in amphetamine-treated cats. L-Dihydroxyphenylalanine (L-DOPA, 20 mg/kg i.p.) greatly potentiated these behaviors in cats chronically treated with amphetamine, but L-DOPA was totally ineffective in eliciting these behaviors in naive animals. The behavioral effects of apomorphine (2 mg/kg i.p.) were also significantly potentiated by chronic amphetamine pretreatment. The amino acid precursor of DA, L-tyrosine (25 mg/kg i.p.), and a DA reuptake blocker, bupropion (5 mg/kg i.p.) were without significant effect on these behaviors in amphetamine-treated cats. The data suggest that these cat behaviors are elicited by an action at central DA receptors and that these receptors become supersensitive following chronic amphetamine administration. Furthermore, there may be a qualitative change in DA receptors, since L-DOPA is very effective in potentiating these behaviors in cats treated chronically with amphetamine, but is totally ineffective in naive cats.
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PMID:Behavioral effects of serotonergic and dopaminergic drugs in cats following chronic amphetamine administration. 673 30

1 N,N-Dimethyltryptamine (DMT) in pargyline pretreated rodents induced a dose-dependent behavioural syndrome consisting of hyperactivity, prostration and hindlimb abduction, mild tremor, Straub tail, retropulsion and jerking. 2 In rats pretreated with pargyline, the behavioural syndrome induced by DMT differed from that induced by L-tryptophan or quipazine, in the lack of forepaw treading and head-weaving and in the presence of only mild tremor. 3 The hyperactivity component of the DMT-induced behavioural syndrome in pargyline-pretreated mice was potentiated by cyproheptadine, methergoline, and mianserin, inhibited by cinanserin, haloperidol, pimozide, methiothepin and propranolol, and not affected by 501C67-sulphate and methysergide. 4 The maximal behavioural changes induced by DMT in rats, other than hyperactivity, were unaffected by pretreatment with cyproheptadine, methysergide, and cinanserin. However, propranolol reduced the intensity of all behavioural effects apart from body jerking, and methergoline decreased the duration of prostration. Phenoxybenzamine and haloperidol, in contrast, enhanced prostration. 5 DMT plus pargyline did not induce circling behaviour in mice with a unilateral 6-hydroxy-dopamine lesion of the nigro-striatal pathway. 6 The DMT-induced behavioural syndrome appears to consist of two components, (a) hyperactivity and (b) other behavioural changes. They differ in their response to drugs affecting brain monoamines. The hyperactivity component may be expressed via dopamine mechanisms, but the other behavioural changes are not. The two behaviours do not respond consistently to drugs believed to alter brain 5-hydroxytryptamine function.
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PMID:Behavioural changes induced by N,N-dimethyl-tryptamine in rodents. 676 27

Serotonin mediated bulbospinal motor activities were examined in rats with experimental allergic encephalomyelitis (EAE)-induced-paraplegia. Treatment with monoamine oxidase inhibitors and L-tryptophan failed to elicit the components of the serotonin syndrome which involved levels of the neuraxis manifesting flaccid paralysis. Straub tail, hindlimb abduction and hindlimb rigidity did not occur. The motor responses represented at spinal segments just above the level of paraplegia, lateral head weaving and forepaw treading, were present but altered in the diseased rats. No impairment was evident in the production of head tremor or hyper-reactivity to accoustic and tactile stimuli. Similarly, in urethane-anesthetized EAE rats, serotonergically-evoked automatic swallowing activity was unchanged as judged by the effects of serotonin receptor agonists, and a serotonin precursor, a reuptake blocker and an antagonist. Our data support the conclusion that EAE-induced impairment of serotonergic neurotransmission is correlated with motor deficits manfested during the acute paralytic stage of the disease.
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PMID:Central serotonin receptor sensitivity in rats with experimental allergic encephalomyelitis. 696 16

The hydrochloride salt of 2,3,3a,4,5,6-hexahydro-8-methyl-1H-pyrazino[3,2,1-j,k]carbazol hydrochloride (pirlindole) exerts pharmacological effects typical of antidepressants. This compound antagonizes the depressant effects of reserpine and tetrabenazine and potentiates the central effects of amphetamine and l-dopa. It also enhances the head-twitch effect of 5-hydroxy-tryptophan, the effects of noradrenaline, adrenaline, serotonin, tyramine on blood pressure as well as the hypertensive and tremor activities of tryptamine. Pirlindole inhibits the neuronal uptake of noradrenaline and exerts reversible, short-lasting anti-MAO activity. It does not possess anti-cholinergic activity. Clinical trials have shown pirlindole to be effective as an antidepressive drug.
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PMID:Pharmacological properties of 2,3,3a,4,5,6-hexahydro-8-methyl-1H-pyrazino [3,2,1-j,k]carbazol hydrochloride (pirlindole), a new antidepressant. 719 96

Vitreoscilla, a gliding bacterium in the Beggiatoaceae, is an obligate aerobe in which cytochrome o functions as the terminal oxidase. Protoheme IX is the only heme type present in this organism. The yield and heme content of Vitreoscilla cells grown in yeast extract, peptone, and acetate were dependent on growth conditions. Cells harvested in early stationary phase contained roughly three times as much heme as cells in early log phase. There was an optimal shaking rate for maximum heme content of cells harvested in stationary phase at fixed initial nutrient concentration. The heme content of cells grown at a fixed shaking rate increased from 5 nmol/g (wet weight) in media which had low nutrient concentration to a maximum of 45 nmol/g (wet weight) in media which had high nutrient concentration, and there was a corresponding sixfold increase in cytochrome o content and an eightfold increase in respiratory rate, evidence that some of the additional heme was incorporated into respiratory pigments. Heme content may be controlled jointly by competition for oxygen and availability of nutrients. Temperature and initial pH affected the growth rate but not the final yield or heme content. Growth rate was optimal at pH 8.0 to 8.5. A defined medium for Vitreoscilla, which is based on glutamate as the carbon source, is described; the other organic components of this medium are acetate, tryptophan, thiamine, biotin, and riboflavin.
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PMID:Effect of growth conditions on yield and heme content of Vitreoscilla. 737 68

There is a new, potentially fatal disorder that is infrequently reported. The apparent rareness may be because of a lack of recognition of the syndrome or its predisposing factors. Fluoxetine (Prozac, Dista Products Co, Division of Eli Lilly Co, Indianapolis, IN), sertraline (Zoloft, Roerig Division, Pfizer Inc, New York, NY), and paroxetine (Paxil, SmithKline Beecham Pharmaceuticals, Philadelphia, PA) belong to a new class of antidepressant medication: the serotonin reuptake-inhibitors (SRIs). The relative safety profile of the SRIs has led to their widespread use. However, a syndrome of excessive serotonergic activity, the "serotonin syndrome" (SS), has recently been recognized. It is characterized by changes in mental status, hypertension, restlessness, myoclonus, hyperreflexia, diaphoresis, shivering, and tremor. A high index of suspicion is required to make the diagnosis in these acutely ill patients. The most common agents implicated in SS are the monoamine oxidase inhibitors in combination with L-tryptophan or fluoxetine. A case of a patient with significant peripheral vascular disease who developed SS while taking paroxetine and an over-the-counter cold medicine is reported. There have been no prior reports of this interaction. Discontinuation of the offending agents, sedation, and supportive care are the mainstays of treatment. The interactions of serotonin with platelets and vascular endothelium are also discussed.
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PMID:The serotonin syndrome associated with paroxetine, an over-the-counter cold remedy, and vascular disease. 766 67

Exposure to HBO causes hypothermia, bradycardia, head weaving, resting tremor, piloerection, and straub tail in rats. These physiological and behavioral responses can also be evoked by selective activation of serotonin1A (5-HT1A) receptors. The purpose of the current study was to determine if hypothermia caused by HBO is due to increased activation of 5-HT1A receptors. The levels of brain biogenic amines were measured in brain regions of Sprague-Dawley (SD) rats exposed to HBO. Exposure to HBO caused an increase in the levels of 5-hydroxyindoleacetic acid (5-HIAA) in the striatum (92%, p < 0.05) and occipital-temporal cortex (116%, p < 0.05), but not in other brain regions. Exposure to HBO did not change the levels of tryptophan, serotonin (5-HT), other biogenic amines, or their metabolites. It is hypothesized that the Fawn Hood (FH) rat, which is reported to be resistant to hypothermia induced by 8-hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT), has an abnormality of 5-HT1A receptor activity. Although the FH rat was more resistant to hypothermia induced by HBO than the SD rat, we were not able to confirm that this rat was resistant to hypothermia induced by 8-OH-DPAT. The 5-HT receptor antagonists, 1-(1H-Indol-4-yloxy)-3-[(1-methylethyl)amino]-2-propanol (Pindolol), 1-(2-methoxyphenyl)-4-[4-(2-phthalimido)butyl] piperazine hydrobromide (NAN-190), and methysergide, did not block hypothermia induced by HBO in SD rats. A series of control experiments were used to confirm that the antagonists blocked hypothermia induced by serotonin agonists.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Hypothermia induced by hyperbaric oxygen is not blocked by serotonin antagonists. 844 68

In animals the occurrence of a behavioural syndrome consisting of hyperactivity, stereotyped movements and increase of temperature has been induced by MAOIs, 5-HT precursors (L-tryptophan) and 5-HT reuptake inhibitors. Most of these manifestations were specifically blocked by a pretreatment with an inhibitor of serotonin synthesis. In humans, the association of myoclonus, diarrhea, confusion, hypomania, agitation, hyperreflexia, shivering, incoordination, fever and diaphoresis, when patients are treated with serotoninergic agents, could constitute a "serotonin syndrome". Such cases of serotonin syndrome were reported after treatments with L-tryptophan, MAOIs, serotonin reuptake inhibitors and tricyclics alone or in association. The authors prospectively evaluated all the "serotonin-related" symptoms in 38 depressed inpatients fulfilling DSM III-R criteria of major depression. 16 (42%) out of 38 patients presented at least one symptom of serotonin syndrome. In 14 cases tremor and myoclonus occurred simultaneously and 10 patients presented at the same time tremor, myoclonus, diaphoresis and shivering. Except for two patients, symptoms were transient, lasted less than one week and disappeared with the pursuit of the treatment. Most often, serotonin syndrome thus corresponds to a reaction induced by a combination of serotoninergic agents at high dosages. In very rare cases, a toxic and potentially fatal interaction can occur between MAOIs, tricyclics and selective serotonin reuptake inhibitors at therapeutic dosages. Serotonin syndrome also provides an heuristic model of the putative mode of action of antidepressants. Serotonin-related symptoms are the physical and objective expression of the antidepressant-induced increase in serotonin. The specificity of serotonin-related syndrome also needs to be discussed since most of the symptoms, such as tremor and diaphoresis, are not in all cases related to an increase in serotonin.
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PMID:[The serotonin syndrome: review of the literature and description of an original study]. 852 62


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