Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0030567 (Parkinson's disease)
 63,064 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Urinary excretion of catecholamines under insulin hypoglycemia was studied in cerebral infarct patients as well as in patients with Parkinson's disease and subjects with lumbar discopathy (control group). While in the last two categories of subjects a normal response to hypoglycemia, i.e., an increase in urinary excretion of epinephrine was noticed, no such increase was found in patients with cerebral infarction. The disorder is attributed to the unresponsiveness to hypoglycemia of the brain stem centers controlling epinephrine secretion.
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PMID:Unresponsiveness to hypoglycemia of centers controlling epinephrine release in cerebral infarct patients. 39 98

The effects of insulin-induced hypoglycemia on catecholamine secretion were investigated in patients with various neurological disorders affecting the autonomic nervous system. In control subjects, insulin-induced hypoglycemia resulted in marked increases in plasma epinephrine and norepinephrine levels. Heart rates were increased within 15 minutes after the insulin injection which were associated with slight elevation and depression of systolic and diastolic blood pressure, respectively. In patients with upper level spinal cord lesions (C1-T6) of various etiology, Shy-Drager syndrome and familial amyloidosis, insulin-induced hypoglycemia failed to increase plasma epinephrine and norepinephrine levels and resulted in falls in systolic and/or diastolic blood pressure 15 minutes after the injection. Heart rates were increased at 30-45 minutes after the injection. In patients with lower spinal cord lesions (T10-L1), neurosyphilis or brain stem tumor with orthostatic hypotension, the catecholamine responses were normal and blood pressure did not fall during insulin-induced hypoglycemia. In patients with Parkinson's disease and spinocerebellar degeneration with autonomic symptoms catecholamine responses were not impaired. These findings suggest that any lesion involving the sympathetic efferent systems of baroreflex such as the spinal descending pathway, sympathetic preganglionic neuron and peripheral nervous system causes both impairment of catecholamine secretion and a fall in blood pressure during hypoglycemia, and that lesions in sympatho-afferent system may not affect the secretion of catecholamine and neural control of blood pressure.
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PMID:[Effects of insulin-induced hypoglycemia on catecholamine secretion and blood pressure in neurological disorders affecting autonomic nervous system]. 162 51

Amino acids such as L-glutamate und L-aspartate are major excitatory neurotransmitters in the mammalian central nervous system (CNS) and potential neurotoxins (excitotoxins), which can destroy central neurons by excessive activation of respective receptors. In the last three decades evidence has accumulated that excitatory amino acids (EAA) are involved in many neurological diseases and that pharmacological intervention offers prospects of novel and more effective therapies. Three different receptor types for EAA have been identified, each being named by the selective agonist to which it is preferentially sensitive, i.e. N-methyl-D-aspartate- (NMDA), kainate- and quisqualate-receptors. In this review interest is focused primarily on the NMDA-receptor, whose structure has been subject of numerous electrophysiological and biochemical studies. Today, it is well established that the NMDA-receptor-ionophore complex has an agonist binding site for glutamate, NMDA and related EAAs which is coupled with an ion channel permeable to Na+, K+, Cl- and Ca2+. Four other binding sites for glycine, phencyclidine, Mg2+ and Zn2+ have been identified which can differentially modulate the function of the NMDA receptor. An additional polyamine binding site has recently been reported. Numerous studies on experimental animals demonstrate that modulators of NMDA-mediated neurotransmission may have antiepileptic, anxiolytic, muscle-relaxant and memory-enhancing effects. Particular interest has gained the possible neuroprotective efficacy of NMDA-receptor antagonists in neurological diseases such as hypoxia/ischemia, hypoglycemia, epilepsy and chronic neurodegenerative disorders (Huntington's, Alzheimer's and Parkinson's disease, amyotrophic lateral sclerosis, and AIDS encephalopathy).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[The N-methyl-D-aspartate receptor complex. Various sites of regulation and clinical consequences]. 197 26

Energy expenditure was determined in 18 patients with Parkinson's disease, 6 healthy volunteers and 6 patients with essential tremor, age-matched, using the indirect calorimetric method which measures the gas exchange rate. The results showed a significant increase in the relative energy expenditure, i.e. the difference between absolute and predictable values from the Harris and Benedict equation, among the parkinsonian patients (+21 +/- 4.1 p. 100; mean +/- S.E.M.) as compared to the 2 control groups (-8.6 +/- 7 p. 100 and -2.1 +/- 4.1 p. 100 respectively; p less than 0.001). There was no correlation between the rate of energy expenditure and the duration or degree of severity of the disease, and particularly the occurrence and magnitude of weight loss, which is frequently observed during the course of the disease. The relative energy expenditure was not significantly different between untreated and treated parkinsonian patients (18.8 +/- 3 p. 100 and 24.5 +/- 6.2 p. 100 respectively). Further investigations were designed to determine whether the increased energy expenditure could reflect a functional impairment of the automatic nervous system. The integrity of the vagus nerve was tested by plotting vs time the plasma Pancreatic Polypeptide levels in response to insulin-induced hypoglycaemia. A physiological stimulation was obtained in the 8 parkinsonian patients studied. This is not the case in chronic autonomic failure. On the contrary, the relative energy expenditure was significantly decreased in the 6 patients that were given a beta-blocking drug, pindolol, 15 mg daily for 3 weeks (+30.7 +/- 4.3 p. 100 before and +21 +/- 4.2 p. 100 after treatment; p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Increase of energy expenditure in Parkinson's disease]. 201 81

This report discusses the clinical significance of bilateral parietal abnormalities on I-123 IMP SPECT imaging in 158 patients with cerebral disorders. This pattern was seen in 15 out of 21 patients with Alzheimer's disease; it was also seen in 4 out of 5 patients with Parkinson's disease with dementia, in 3 out of 17 patients with vascular dementia, in 1 out of 36 patients with cerebral infarction without dementia, in 1 out of 2 patients with hypoglycemia, and in 1 out of 2 patients with CO intoxication. Detection of bilateral parietal abnormalities is a useful finding in the diagnosis of Alzheimer's disease, but one should keep in mind that other cerebral disorders may also show a similar pattern with I-123 IMP SPECT imaging.
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PMID:Differential diagnosis of bilateral parietal abnormalities in I-123 IMP SPECT imaging. 227 32

Thirteen drug-free and not severely affected patients with idiopathic Parkinson's disease underwent an insulin-hypoglycaemia test, a TRH test and a levodopa test. The responses of growth hormone, prolactin, cortisol and thyrotropin were measured, and retested under stable therapy with levodopa and benserazide. Mean basal and stimulated hormonal concentrations were in the normal range before and during therapy. Minor abnormalities were observed in individual cases, but did not indicate a hypothalamic dopamine deficit.
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PMID:Effect of hypoglycaemia, TRH and levodopa on plasma growth hormone, prolactin, thyrotropin and cortisol in Parkinson's disease before and during therapy. 308 17

Excitotoxic cell death is hypothesized to contribute to numerous neuropathologic conditions, including hypoxic/ischemic encephalopathy, hypoglycemia, Parkinson's disease, and Huntington's disease. Neuronal death from excitotoxic lesions has been shown to be an active process, with activation of immediate early gene transcription, resulting in secondary changes in gene expression. Another feature of neurotoxic cell death that has been examined is the presence of DNA fragmentation, which presumably indicates impending nuclear disintegration. A technique has been described for labeling fragmented DNA in situ, allowing precise determination of the anatomic and temporal distribution of neurons after an excitotoxic lesion. To investigate this phenomenon, we performed in situ nick translation on brain tissue from rats that have undergone stereotaxically placed intrastriatal quinolinic acid injections. Furthermore, in these same animals we analyzed the expression of c-fos mRNA to compare the time course and regional distribution of DNA fragmentation with immediate early gene activation after an excitotoxic lesion. Our analysis indicates that c-fos expression increases soon after quinolinic acid injection, is widespread in rat brain, but is effectively absent by 24 h postinjection. DNA fragmentation, however, is limited to striatum and is maximal at 24 h after injection. These results demonstrate the sensitivity of in situ nick translation for the detection of regional neuropathology and illustrate the temporal and spatial relationship of c-fos expression to excitotoxic neuronal death.
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PMID:DNA fragmentation and immediate early gene expression in rat striatum following quinolinic acid administration. 764 26

Treatment with selegiline produced profound hypoglycemia in a 70-year-old man with Parkinson's disease. The hypoglycemia was accompanied by hyperinsulinemia and persisted for 1 week after selegiline was discontinued. Although this side effect of antidepressant monoamine oxidase inhibitors was well documented in 1959-1968 publications, it was not known to the manufacturer of selegiline. Effects of drugs on glucose metabolism may be predictable through a novel molecular modeling technique developed in our laboratories, which shows that glucose exhibits stereochemical complementarity to a specific site in partially unwound DNA. Selegiline and other molecules affecting glucose metabolism fit into the same DNA base sequence. It therefore should be possible to employ this technique to identify pharmaceutical agents that possess hypoglycemic or hyperglycemic effects in vivo.
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PMID:Hypoglycemia caused by selegiline, an antiparkinsonian drug: can such side effects be predicted? 813 55

Central autonomic dysfunctions can be due to primary (degenerative) or secondary disorders. Autonomic failure (AF) may be a major manifestation of multiple system atrophy (MSA) and idiopathic Parkinson's disease (IPD). In both MSA and IPD, AF is almost invariably associated with neuronal loss in the intermediolateral cell columns. Dysautonomia in MSA is early, severe, and progressive, including marked orthostatic hypotension and urinary incontinence and is complicated by respiratory disturbances, such as laryngeal stridor and sleep apnea. MSA/AF can be differentiated from primary (or pure) autonomic failure (PAF) without central nervous system involvement. PAF is mainly a disorder of the postganglionic neurons. In contrast to PAF, MSA/AF has preserved basal sympathetic activity, decreased cerebrospinal fluid (CSF) neurotransmitter markers, impaired vasopressin response to hypotension, and impaired adrenocorticotrophic hormone/beta endorphin response to hypoglycemia. AF in IPD is generally less severe than in MSA. Poor response to L-Dopa, abnormal urethral sphincter electromyography, and CSF markers may distinguish MSA from IPD. Secondary autonomic disorders may result from traumatic, vascular, inflammatory, demyelinating, or neoplastic lesions involving corticolimbic, hypothalamic, brainstem, or spinal autonomic network. These disorders can cause AF or autonomic hyperactivity, such as arrhythmia, hypertension, and hyperthermia. However, many disorders may only produce subclinical abnormalities.
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PMID:Central autonomic disorders. 845 95

In-vivo microdialysis has been used extensively to study the neurochemical mechanisms of ischemia, epilepsy and hypoglycemia. It is also being increasingly used to document the response of neurons to various medications. Most of the work to date has been done in small animals. In the last 2 years, the technique has been adapted for use in patients with subarachnoid hemorrhage, head trauma, Parkinson's disease, brain tumors and epilepsy. Two of the major limiting factors are the invasiveness of the technique and the resultant potential for CNS infection. We describe a simple, safe and reliable method to measure neurochemical changes in the human brain with in-vivo microdialysis. We were able to easily monitor for 4-6 h daily for up to 4 days in awake or comatose patients with subarachnoid hemorrhage or head trauma. Cerebral concentrations of glutamate, GABA, other amino acids and catecholamines were measured. This technique thus has a potential for on-line measurements of neurotoxins in patients with unstable neurological conditions.
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PMID:A new method of in-vivo microdialysis of the human brain. 854 74


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