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)

Chronic treatment with beta-blockers was interrupted abruptly in six patients with arterial hypertension. Three patients, who had experienced symptoms during a previous withdrawal, again complained of transient palpitations, tremor, sweating, headache and general malaise. A significant increase in standing blood pressure (BP) and heart rate (HR) was noted after 24 h. The standing HR reached a maximum after 48 h and had decreased significantly on the 7th day (p less than 0.005). There was a strong tendency to greater increase in standing BP and HR in the patients who experienced symptoms than in those who did not. Plasma concentrations of noradrenaline, adrenaline and prolactin did not change significantly. Thus, beta-blocker withdrawal symptoms are reproducible and are indicative of a transient sympathetic hyperresponse. The increased activity is not likely to be caused by increased production of circulating catecholamines, but rather by increased sensitivity of the beta-receptor.
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PMID:Abrupt withdrawal of beta-blocking agents in patients with arterial hypertension. Effect on blood pressure, heart rate and plasma catecholamines and prolactin. 3 93

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.
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PMID:Drug concentrations in neuropsychiatry: alternative approaches. 26 86

The serotonin precursor, 5-hydroxytryptophan (5-HTP), can induce a behavioral syndrome characterized by rigidity, splayed feet, tremor, head weaving, salivation and forepaw treading. This response to 5-HTP was markedly potentiated in adult rats treated intracisternally with 5,7-dihydroxytryptamine (5,7-DHT) during development. Prevention of the 5,7-DHT-induced reduction of brain norepinephrine with pargyline or desipramine did not diminish the potentiation of 5-HTP, suggesting that noradrenergic fibers are not contributing to the altered 5-HTP response. It was also found that treatments with 5,7-DHT potentiated the release of prolactin and the disruption of responding in a fixed-ratio operant task induced by 5-HTP. Other experiments indicated that 5,7-DHT treatments potentiated 5-HTP without affecting the action of L-dihydroxyphenylalanine. In addition, administration of the decarboxylase inhibitor, R0-4-4602, at a dose that inhibits enzyme activity in brain, blocked the 5-HTP-induced behavioral syndrome in 5,7-DHT-treated rats, indicating that 5-HTP must be converted to serotonin for 5-HTP to alter behavior. Thus, the present studies indicate that destruction of serotonergic fibers during development can produce permanent changes in central serotonergic mechanisms.
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PMID:Behavioral and prolactin responses to 5-hydroxytryptophan in rats treated during development with 5,7-dihydroxytryptamine. 30 87

Six normal men ingested thioridazine, high and low doses, and placebo on three occasions. Their plasma and urinary thioridazine and mesoridazine plus sulforidazine were measured over 5 hr, together with their plasma prolactin, and a battery of psychophysiologic variables. Drowsiness and EEG changes correlated highly with rise in prolactin, but not with drug plasma concentrations. Finger tremor increased, and some psychologic tests were impaired by thioridazine; other psychologic tests, the auditory-evoked response, and palmar skin conductance were unaffected and showed no relationship to drug or prolactin levels. This suggests that plasma prolactin may be a useful indicator of some aspects of the individual's response to a psychotropic drug, and possibly a better guide to the selection of a suitable drug and its appropriate dose in clinical practice than the measurement of plasma concentrations of the drug itself.
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PMID:Prolactin and psychophysiologic measures after single doses of thioridazine. 84 73

On the basis of a reassessment of the aetiopathogenetic problem and the neuroendocrine implications, the therapeutic effectiveness of a prolactin inhibitor, 2-alpha-Br-ergocryptine (CB 154), in Parkinson's disease is assessed. Five patients were treated for a total of two weeks using doses between 10 and 15 mg/die. CB 154 was found to act as a dopaminergic receptor agonist at nigro-striatal level, considerably improving tremor and rigidity and to a lesser extent bradykinesia and total disability.
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PMID:[Neuroendocrine aspects of Parkinson's disease. Therapeutic/effect of a prolactin inhibitor]. 103 12

The prevalence of neuropsychological and respiratory symptoms, lung ventilatory parameters, neurofunctional performances (visual reaction time, eye-hand coordination, hand steadiness, audioverbal short term memory), and several biological parameters (calcium, iron, luteinising hormone (LH), follicle stimulating hormone (FSH), and prolactin concentrations in serum, blood counts, manganese (Mn) concentration in blood and in urine) were examined in a group of workers (n = 92) exposed to MnO2 dust in a dry alkaline battery factory and a matched control group (n = 101). In the battery plant, the current exposure of the workers to airborne Mn was measured with personal samplers and amounted on average (geometric mean) to 215 and 948 micrograms Mn/m3 for respirable and total dust respectively. For each worker, the lifetime integrated exposure to respirable and total airborne Mn dust was also assessed. The geometric means of the Mn concentrations in blood (MnB) and in urine (MnU) were significantly higher in the Mn exposed group than in the control group (MnB 0.81 v 0.68 microgram/100 ml; MnU 0.84 v 0.09 microgram/g creatinine). On an individual basis, MnU and MnB were not related to various external exposure parameters (duration of exposure, current exposure, or lifetime integrated exposure to airborne Mn). On a group basis, a statistically significant association was found between MnU and current Mn concentrations in air. No appreciable difference between the exposed and the control workers was found with regard to the other biological measurements (calcium, LH, FSH, and prolactin in serum). Although the erythropoietic parameters and serum iron concentration were in the normal range for both groups, there was a statistically significant trend towards lower values in the Mn exposed workers. The prevalences of reported neuropsychological and respiratory symptoms, the lung function parameters, and the audioverbal short term memory scores did not differ between the control and exposed groups. The Mn workers, however, performed the other neurofunctional tests (visual reaction time, eye-hand coordination, hand steadiness) less satisfactorily than the control workers. For these tests, the prevalences of abnormal results were related to the lifetime integrated exposure to total and respirable Mn dust. On the basis of logistic regression analysis it may be inferred that an increased risk of peripheral tremor exists when the lifetime integrated exposure to Mn dust exceeds 3575 or 730 micrograms Mn/m3 x year for total and respirable dust respectively. The results clearly support a previous proposal by the authors to decrease the current time weighted average exposure to Mn dust.
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PMID:Assessment of the permissible exposure level to manganese in workers exposed to manganese dioxide dust. 173 53

This study has been performed to assess the effect of methyldopa (MD) therapy in pregnancy hypertension on the neonatal adaptation. Infants born to mothers on MD for several weeks prior to delivery and presenting with excessive tremor and irritability were evaluated according to the dose of maternal MD. Pregnancy hypertension and high dose MD was associated with impaired placental perfusion, compromised function of fetoplacental unit and more frequent surgical delivery. Infants of mothers on high (1.25-2.0 g/day) or low (less than 1 g/day) MD had gestational age, head circumference, acid-base balance, Apgar score and blood pressure similar to those born to healthy control mothers. The birth weight of infants of the high MD group, however, were significantly lower than in the low-dose or control groups. MD therapy resulted in a dose-dependent increase in plasma levels of prolactin, thyrotropin and triiodthyronine indicating decreased dopaminergic inhibition of pituitary hormone release. Plasma thyroxine concentration, however, decreased significantly. Cerebrospinal fluid noradrenaline was found to be markedly depressed after maternal MD showing disturbed central nervous system monoamine metabolism. It is suggested that MD administration to mothers presenting with pregnancy hypertension interferes with cerebral monoamine metabolism of the neonate and induces alterations in some endocrine functions under dopaminergic control. The possible role of chronic fetal distress frequently associated with pregnancy hypertension should also be considered.
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PMID:Neonatal effects of methyldopa therapy in pregnancy hypertension. 186 78

Ten male inpatients (aged 29 +/- 6 years) with a DSM-III diagnosis of schizophrenia participated in a 4-week open dose escalation study of amperozide, a novel 5-HT2 receptor antagonist. The maximum daily dose of amperozide was 20 mg. A close dose-plasma concentration relationship showed considerable interindividual variation in the steady-state plasma levels at a given dose. Approximately equal concentrations of amperozide and its metabolite, N-deethylated amperozide, were seen in plasma. The prolactin levels were not increased during amperozide treatment. No changes occurred in hematological or other laboratory parameters. ECG showed changes in T-wave morphology and a prolongation of the QTc time. One patient was withdrawn from the trial due to aggravation of psychotic symptoms, and two patients had a brief, temporary discontinuation of the drug due to somatic illness. Six patients were improved during amperozide treatment, as assessed by the Clinical Global Improvement Scale. Among the responders the total CPRS was reduced by a mean of 64% and total BPRS score by a mean of 46%. Mild tremor was a frequent side effect, but other extrapyramidal symptoms were rare. Nausea was seen in six patients and of a more pronounced character in one patient. In general, the severity of the side effects increased with increasing doses of amperozide.
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PMID:Effects of amperozide in schizophrenia. An open study of a potent 5-HT2 receptor antagonist. 192 36

The effects of a thyrotropin-releasing hormone (TRH) analogue, MK-771, in comparison with TRH and another TRH analogue, DN-1417, on body shaking and prolactin secretion were investigated in estrogen-primed and nonprimed rats. Intraperitoneal injections of TRH (20, 40 mg/kg), MK-771 (0.5-4 mg/kg) or DN-1417 (5-20 mg/kg) elicited marked body shaking in male rats. MK-771-induced shaking did not increase upon daily administration of the drug (0.5 mg/kg, s.c.) for 20 days or after treatment with estradiol benzoate (35 micrograms/kg, s.c.) for a 3 days period. Furthermore, following daily administration of MK-771 (0.5 mg/kg, s.c.) for 20 days, serum prolactin levels remained unchanged in male rats. Behaviorally active doses of TRH (20 mg/kg, i.p.), MK-771 (2 mg/kg, i.p.) and DN-1417 (10 mg/kg, i.p.) also failed to elevate serum prolactin levels in both ovariectomized rats and normal male rats. These drugs did, however, markedly elevate prolactin levels which had been increased in estrogen-primed male rats. The results suggest that TRH, MK-771 and DN-1417, in behaviorally active doses, exert a marked endocrine effect on prolactin secretion in estrogen-primed rats, but not in ovariectomized rats or normal male rats.
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PMID:Effects of thyrotropin-releasing hormone analogues on body shaking and prolactin levels in estrogen-primed and nonprimed rats. 249 89

The possibility of the presence of chronic tolerance to the analgesic effect of prolactin and of dependence was tested. Repeated administration of prolactin resulted in the loss of analgesic activity, indicating the development of chronic tolerance. Neither a high dose of, or chronic treatment with prolactin followed by naloxone elicited any characteristic withdrawal signs, suggesting the absence of dependence. Similarly, abrupt withdrawal of prolonged prolactin treatment also did not elicit withdrawal signs. However, in the same model, the morphine-naloxone combination and spontaneous withdrawal of chronic morphine treatment produced characteristic withdrawal signs, namely jumping, wet shakes, and body tremor. The data support the view that tolerance and dependence can be dissociated from each other and that different mechanisms may operate in these phenomena. The absence of liability to dependence with prolactin strengthens the contention that prolactin may be a potential drug for combatting opiate dependence.
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PMID:An investigation into the possible development of chronic tolerance to analgesia and dependence on prolactin. 289 46


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