Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0011570 (depression)
 172,036 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Acivicin (AT-125) is a glutamine antagonist with dose-limiting, schedule-dependent CNS toxicity and predictable CSF penetration after intravenous administration. Because of these properties, a trial in CNS malignancies was initiated. Thirty-two patients with recurrent or residual malignant astrocytomas were treated with AT-125. The majority of patients had glioblastoma multiforme (24) and had received prior nitrosoureas (21). The median age was 50 years, and Southwest Oncology Group (SWOG) performance status was 2. The major determinant of response was based upon radiologic criteria using computed tomographic (CT) scanning and/or magnetic resonance imaging (MRI) scans. The tumor mass was measured in two perpendicular planes, which yielded the largest cross-sectional area. Standard solid tumor criteria for response were used. All responding patients also had a stable or tapered dose of corticosteroids with stable or improved performance status and neurologic examination. There were four objective responses (12%): one complete remission (3 1/2+ years) and three partial remissions (57, 86, and 322 days). Two patients had improvement in disease that did not meet requirements for a partial remission. Toxicity was mild and primarily consisted of nausea, vomiting, and lethargy. Two patients were removed from study due to neurotoxicity (depression and hallucinations). The strict response criteria used in this trial were not those that have been used in testing other active agents such as carmustine (BCNU). We conclude that AT-125 has objective antitumor activity in malignant astrocytomas and warrants further study.
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PMID:Objective antitumor activity of acivicin in patients with recurrent CNS malignancies: a Southwest Oncology Group trial. 164 69

The sites of action of spinally administered opiates are specific receptors (mu kappa delta) located in the spinal dorsal horn. Pharmacokinetics of spinally administered opiates are determined by their lipophilic property. Morphine has a weak octanol-water partition coefficient and remains in the CSF during a long period following the cephalic movements of lumbar CSF to the supraspinal structures. More lipophilic opiates are rapidly eliminated from the CSF. Nevertheless, significant pethidine concentrations are documented in the ventricular CSF, due to vascular absorption of the drug. Pharmacokinetics features of different opiates determine the duration of analgesia and the risk of respiratory depression after spinal injection.
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PMID:[Pharmacology and mechanism of action of opiates administered by the subarachnoid route]. 167 77

We investigated the perceived role of stressful events in episodes of major affective disorder in patients studied in the NIMH Clinical Research Branch Collaborative Program on the Psychobiology of Depression (Biological Studies). Using items from the Schedule for Affective Disorders and Schizophrenia (SADS), episodes were divided into environment-sensitive (high perceived role of stressful events) and autonomous (minimal or no perceived role of stressful events). Patients with environment-sensitive episodes had fewer previous episodes and a longer index episode. The groups did not differ with respect to age, gender, education, socioeconomic group, diagnosis, severity of illness, or eventual response to treatment. Unipolar depressed patients with environment-sensitive episodes had lower CSF 5-HIAA than those with autonomous episodes. Among bipolar depressed patients, those with autonomous episodes had elevated excretion of O-methylated catecholamine metabolites and of epinephrine, while those with environment-sensitive episodes had normal excretion of catecholamines and metabolites. Manic subjects with environment-sensitive episodes had elevated norepinephrine excretion, while this was normal in manics with autonomous episodes. Relationships between environmental sensitivity of affective episodes and neurotransmitter function therefore appear to be related to the type of episode.
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PMID:Stress, depression, and mania: relationship between perceived role of stressful events and clinical and biochemical characteristics. 169 33

Among Parkinson's disease (PD) patients complaining of pain, 10 with pain not associated with a motor fluctuation or L-dopa therapy were evaluated. The controls were 14 PD without pain and eight with thalamic pain syndrome. The threshold of pain and neurotransmitters in CSF were measured in the three groups. In PD with pain, the maximum tolerance level and tourniquet pain ratio decreased significantly. In PD with pain, the score on the self-depression scale increased significantly and 5-hydroxy-indole acetic acid (5-HIAA) among the neurotransmitters decreased significantly. These results suggest that decreases in the threshold of pain and changes of serotonin in CSF are involved in the development of specific pain in PD who do not respond to L-dopa.
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PMID:The threshold of pain and neurotransmitter's change on pain in Parkinson's disease. 170 99

By means of a review of genetic, biological and neurophysiological studies, we attempted to validate the DSM III-R depressive disorder categories. Genetic studies support the distinction between bipolar and recurrent major (unipolar) depression although genetic heterogeneity and variable phenotypic expressivity have been suggested in bipolar depression. Biological and neuroendocrine abnormalities in depression seem to relate more to a particular symptomatological profile than to a specific depressive subtype including the bipolar-unipolar dichotomy. For example, catecholamines and serotonin metabolism seem to reflect respectively psychomotor status and aggressiveness in depression. Using genetic and biological criteria, major depression with psychotic features is the best validated category of the four main DSM-R major depressive subclasses or specifications (psychotic, chronic, melancholic, seasonal). Psychotic depression seems to constitute the most coherent subgroup and biological abnormalities such as dexamethasone non suppression and shortened REM latency are very often observed. An important confounding variable in these biological validation studies is the severity of the depressive state. Psychotic depression is considered to be a more severe depressive subtype and also shows marked biological disturbances. Conversely, in seasonal depression, a less severe depressive subtype, CSF monoamine metabolism abnormalities, dexamethasone non suppression and shortened REM latency could not clearly be demonstrated. Genetic studies show that early onset dysthymia and cyclothymia could be part of the affective spectrum and some maintain that these two clinical entities are attenued forms of bipolar or recurrent major depression.
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PMID:[Biological psychiatry and current classifications of depressive disorders]. 186 51

Previous work has demonstrated that there is a selective increase in extracellular taurine in the brain during acute water intoxication. One aim of the present study was to investigate whether plasma taurine contributes to this increase. To this end, the concentrations of taurine, other amino acids, and ethanolamine (EA) were measured in plasma and CSF of urethane-anesthetized rats injected with 150 ml/kg body weight of distilled water. Blood pressure, blood gases, and pH, as well as plasma and CSF osmolality, were also measured. The CSF level of albumin was quantitated to study the function of the blood-CSF barrier. In separate experiments, hippocampal microdialysis was performed to determine the effects of acute plasma hypoosmolality on extracellular amino acids. Finally, the effect of water injection on hippocampal specific gravity and tissue amino acids was assessed. Blood gases and pH were essentially unchanged after water administration. Mean arterial blood pressure increased to peak levels approximately 50 mm Hg above control. Plasma osmolality decreased rapidly, whereas the depression of CSF osmolality was slower and less pronounced. The average volume of the hippocampus increased by 8%. Water injection was accompanied by a 25-fold elevation of taurine in plasma, whereas phosphoethanolamine (PEA) and EA increased moderately. A small fraction of the increase in plasma taurine might derive from blood cells because dilution of blood in vitro led to doubled plasma levels of the amino acid. Taurine, PEA, and EA increased consistently in CSF and hippocampal microdialysates. Plasma hypoosmolality transiently opened the blood-CSF barrier is reflected by augmented CSF concentrations of albumin.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Elevation of taurine in hippocampal extracellular fluid and cerebrospinal fluid of acutely hypoosmotic rats: contribution by influx from blood? 189 10

Total and free concentrations of T4 and rT3 in serum and cerebrospinal fluid were estimated by ultrafiltration in 12 patients with unipolar endogenous depression before and after electroconvulsive treatment. Recovery from depression resulted in a decrease in CSF concentrations of free T4 (median) (26.2 to 21.4 pmol/l, p less than 0.02) and free rT3 (14.1 to 12.3 pmol/l, p less than 0.05). Concentrations of free T4 in the cerebrospinal fluid were lower than those in serum (p less than 0.02), the ratio being 0.6. In contrast, levels of free rT3 in the cerebrospinal fluid were considerably higher than those found in serum (p less than 0.01), the ratio being 25. These ratios did not change following recovery from depression. In 9 patients with nonthyroidal somatic illness, concentrations of free T4 and rT3 in the cerebrospinal fluid were similar to those found in patients with endogenous depression, whereas 4 hypothyroid patients and one hyperthyroid patient had considerably lower and higher, respectively, concentrations of both free T4 and rT3. In conclusion, levels of free T4 and free rT3 in the cerebrospinal fluid are increased during depression compared with levels after recovery, probably reflecting an increased supply of T4 from serum and an increased production of rT3 from T4 in the brain. The data also suggest that the transport of iodothyronines between serum and the cerebrospinal fluid is restricted.
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PMID:Free thyroxine and 3,3',5'-triiodothyronine levels in cerebrospinal fluid in patients with endogenous depression. 190 Jun 53

The role of prostanoids in mediating cerebrovascular responses to cortical spreading depression (CSD) was examined in anesthetized rabbits. CSD was elicited by KCl microinjection, and its propagation was monitored electrophysiologically. Pial arterial diameter was determined using a closed cranial window and intravital microscopy, and regional cerebral blood flow (rCBF) was determined using laser flowmetry. Levels of peri-arachnoid cerebrospinal fluid prostanoids were determined by radioimmunoassay. CSF increased pial arteriolar diameter 62% and rCBF 354% over the baseline levels. Locations of propagating CSD, dilating pial arteriole, and increased rCBF were always closely associated spatiotemporally. Cerebrospinal fluid prostanoid levels increased during single CSD-induced arteriolar dilation, and they were further augmented during multiple CSDs. Indomethacin enhanced both CSD-induced vasodilation (88%) and rCBF increase (580%), but it decreased the cerebrospinal fluid levels of prostanoids below the baseline levels and prevented their increase during CSD-induced vasodilation. These results indicate that prostanoids are synthesized from neurons or glial cells and/or the brain vessels and, as the net result, counteract pial arteriolar dilation and rCBF increase during CSD. In addition, they support the hypothesis that the vasodilation is caused primarily by neurogenic factors associated with CSD.
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PMID:Prostanoids attenuate pial arteriolar dilation induced by cortical spreading depression in rabbits. 192 29

Recent studies have linked impulsivity with CSF concentrations of both 5-hydroxyindoleacetic acid (5-HIAA) and homovanillic acid (HVA). One work found a negative correlation between the MMPI psychopathic deviate (Pd) scale and 5-HIAA in personality disordered men (Brown et al., 1982). We found that the 5-HIAA/Pd correlation extends (P less than 0.05) to unmedicated depressed patients (n = 21). A trend was found between HVA and Pd in depression. There was no relationship between either metabolite and the Pd scale in unmedicated schizophrenics (n = 24). A significant inverse correlation was found between the MMPI depression scale and CSF HVA but not 5-HIAA in the depressed patients.
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PMID:MMPI measures of impulsivity and depression correlate with CSF 5-HIAA and HVA in depression but not schizophrenia. 193 32

The involvement of GABAergic systems in the pathogenesis of HE was supported by electrophysiologic studies of single Purkinje neurons from rabbits with HE which demonstrated the hypersensitivity of these neurons to depression by GABA and BZ receptor agonists. In contrast, these neurons were excited by BZ receptor antagonists. At concentrations which had no effect on neuronal activity, BZ receptor antagonists also reversed the hypersensitivity of HE neurons to depression by muscimol. This combination of neuronal responses is consistent with an increase in the concentration or availability of a ligand for the BZ receptor with agonist properties in the brains of rabbits with HE. Subsequent neurochemical studies support these electrophysiologic observations. Autoradiographic techniques indicated the presence of a reversible inhibitor of [3H]Ro 15-1788 and [3H]flunitrazepam binding to the cerebral and cerebellar cortices of rabbits with HE. The ability of this substance to inhibit [3H]flunitrazepam binding to HE rabbit brain sections was further enhanced in the presence of NaCl and GABA. The autoradiographic studies suggested that the density and affinity of the components of the GABA-BZ receptor complex are unaltered in this animal model of HE. This inference is fully supported by the subsequent studies of radioligand binding to well-washed membrane preparations. Finally, extracts of HE rabbit brains yielded a family of substances with the properties of BZ receptor agonists. These substances may include, but are not limited to, diazepam, oxazepam and desmethyldiazepam, but do not include substances commonly elevated in the plasma and CSF of patients with HE4. The positive identification of these substances awaits confirmation by mass-spectroscopic analysis. However, the precedent for the presence of a family of benzodiazepines in animals that were not administered these drugs has been set. The origin of these substances is a matter of ongoing research. Several studies have shown the presence of benzodiazepines in plant and animal materials. It is possible that these "endogenous" benzodiazepines are the result of contamination of the food chain. A normally functioning liver would capture and metabolize these compounds after their absorption from the gut. This function of the liver would be impaired in liver failure, thus allowing sufficient levels of BZ receptor agonists to accumulate in the CNS, contributing to the pathogenesis of HE. However, studies by DeBlas and coworkers have reported that 1,4 benzodiazepines are present in human brains preserved prior to the commercial use of these compounds. Further, they have found benzodiazepines in cell lines cultured without potential exogenous sources of benzodiazepines.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:The involvement of the benzodiazepine receptor in hepatic encephalopathy: evidence for the presence of a benzodiazepine receptor ligand. 196 66


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