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)

There is a suggestive evidence for a relationship between central 5-HT and the occurrence of certain types of depressions. This evidence is derived from three sources: postmortem studies; measurement of CSF 5-HIAA; accumulation of CSF 5-HIAA after transport blockade by probenecid. Disturbances of central 5-HT metabolism are not typical for any depression but for certain types of vital (endogenous) depression. This implies that the group of vital depression, though tending towards homogeneity in terms of symptomatology, is heterogenous in biochemical terms and comprises patients with and without disorders in central 5-HT metabolism. It is plausible that disorders of the 5-HT metabolism play a role in the pathogenesis of depression, instead of resulting from them. This statement is based on the following findings: (i) 5-HTP can abolish or alleviate the depressive syndrome or some of its elements. (ii) This 5-HTP effect can be potentiated by clomipramine (Anafranil), a relative selective inhibitor of 5-HT reuptake. (iii) There exists a negative correlation between 5-HT turnover in the CNS and the therapeutic effect of clomipramine. The alleged distrurbances in central 5-HT are more likely to be predisposing than of direct causative significance. This assumption is based on two observations: (i) In more that 50% of cases, the 5-HT turnover remains low after clinical recovery, the patient being drug-free. (ii) There is suggestive evidence that abolition of the 5-HT deficit (by means of 5-HTP) exerts a prophylactic effect in uni-and bipolar depression.
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PMID:The Harold E. Himwich Memorial Lecture. Significance of biochemical parameters in the diagnosis, treatment, and prevention of depressive disorders. 30 32

5-Hydroxytryptamine (5-HT) and epinephrine were applied by microiontophoresis to single neurons in the isolated spinal cord of the frog. 5-HT depressed all but two of the responsive cells, whereas the response to epinephrine consisted exclusively of depression. 5-HT action was more marked than that of epinephrine on most cells. With either compound, responseve units were diffusely distributed throughout the tissue. While it was proven that prostaglandin E1 (PGE1) exerts a direct excitatory action on spinal neurons, no evidence of an antagonism between PGE1 and the monoamines was obtained. These findings provide additional support to the hypothesis that 5-HT and epinephrine are transmitters in the frog spinal cord. The possibility that PGE1 may 'modulate' the responsiveness of spinal neurons to the monoamines was not confirmed.
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PMID:Microiontophoresis of 5-hydroxytryptamine, epinephrine, and prostaglandin E1 on spinal neurons in the frog. 30 25

Zimelidine, a bicyclic compound, which in animal experiments causes specific inhibition of the uptake of 5-HT, was tried on 15 patients with depression of endogenous type. It produced considerable and highly significant 5-HT uptake inhibition in rat brain slices incubated in blood plasma from the patient under treatment, but no inhibition of NA uptake. Depressive symptoms were effectively relieved or entirely abolished in about two thirds of the patients. Only four patients did not react to the drug, and three of these were probably in need of NA uptake inhibitors, which on other occasions had worked well on their depressions. These three patients showed an extreme degree or retardation. During zimelidine treatment they were not just unaffected but showed signs of excitation, impatience and desperate feelings. These preliminary findings strongly indicate the true existence of depressive cases in need of an NA uptake inhibitor, but completely resistant to a specific 5-HT uptake inhibitor. The final dose of zimelidine was 75 mg b.i.d. This dose, although sufficient in most cases, was obviously somewhat low for a few of our patients. The concentration in blood plasma of zimelidine should probably reach a minimum level of 250 nmol/l and norzimelidine 500 nmol/l, and to achieve this a general dosage of 100 mg b.i.d. is recommended.
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PMID:Preliminary clinical test of zimelidine (H 102/09), a new 5-HT uptake inhibitor. 36 99

Tandamine hydrochloride, a thiopyranoindole, was more active than desmethylimipramine in inhibiting the tyramine pressor response after single oral doses in human volunteers. When compared with a placebo, tandamine was found to possess significant anticholinergic activity, to reduce appetite and to produce sedation. Compared with clomipramine, it caused a smaller inhibition of 5-HT but a more marked inhibition of dopamine uptake into human platelets. Further clinical and pharmacological studies with tandamine may help to elucidate the respective roles of different monoamines in depression, sedation and appetite.
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PMID:Clinical pharmacological studies of tandamine, a potential antidepressive drug. 40 62

The blood platelets, which serious arguments permit one to consider as valid models of serotoninergic neurones, were studied in various types of depression and during treatment with antidepressor drugs. The modifications of several platelet parameters were analysed in particular. The level of hydroxyndoles (OH-5-tryptamine or 5-HT for example) is generally lowered. The uptake of 5-HT is also reduced with normalisation by antidepressor treatments; the fixation of mepacrine, sign of the passive uptake of bioamines, is modified in the same direction, especially, in our experience, in maniacs, with a rise during treatment with phenothiazines. Finally, among the platelet enzymes, monoamine oxidase has a reduced activity in bipolar depressed patients, certain maniac depressive psychosis, and endogenic melancholias. Other platelet parameters, (liberation or release, nucleotide levels, 5-HT bonds at membrane level, etc.) may provide in the future, interesting information. In spite of sometimes contradictory data, the platelet model may be of interest, especially from pharmacological point of view.
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PMID:[The platelet model applied to the study of depressive illness (author's transl)]. 44 12

Clomipramine is the most potent 5-HT reuptake blockade agent among the antidepressants. A comparison between the effect of clomipramine and a less powerful 5-HT reuptake blockade agent (amitriptyline) could test the hypothesis that brain 5-HT is a mediator of pain sensation. Groups of patients of either sex, with pain indication of trigeminal neuralgia, tension headache or postherpatic neuralgia, received doses of clomipramine or amitriptyline in a single blind clinical experiment. The results after three months of treatment showed that clomipramine: (1) was better than amitriptyline in treating trigeminal neuralgia; (2) tended to be better in the treatment of tension headache; and (3) amitriptyline is better in treating postherpatic neuralgia. Clomipramine was better tolerated. The results support the hypothesis that in certain pain situations, clomipramine exerts a beneficial effect, not only because of its effect on the depression and anxiety level of the patient, but also via its effects on the 5-HT brain system.
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PMID:Clomipramine and amitriptyline in the treatment of severe pain. 48 62

The obtained results and data of literature indicate the increase (absolute or relative) of the rate of 5-HT uptake by platelets in depressives. These data suggest that the acceleration of 5-HT reuptake in neurones may be one of the reasons of insufficiency of 5-HT-ergic processes in depression of 5-HT type (Asberg, 1976).
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PMID:The content and uptake of 5-HT by blood platelets in depressive patients. 49 Jan 51

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 flick and abortive groom, characteristic of the action of hallucinogenic drugs and dependent on a depression of central serotonergic neurotransmission. This drug treatment produced large decreases (-40 to -60%) in central nervous system serotonin (5-HT) and its major metabolite, 5-hydroxyindoleacetic acid (5-HIAA), when measured either 6 or 24 hr after the last amphetamine injection. The rate of limb flicking returned to a predrug level approximately 5 days after drug withdrawal, at which time 5-HT and 5-HIAA levels had returned to within 30 to 40% of base line. Both 5-HT and 5-HIAA returned to base-line levels within 14 days after drug withdrawal. Norepinephrine (NE), dopamine (DA) and DA metabolites were decreased 60 to 95% by chronic amphetamine treatment and showed little recovery within the 14 days after drug withdrawal. A second experiment examined the latency to onset of the behavioral and neurochemical changes with a constant dose of amphetamine (7.5 mg/kg, twice daily). Limb flicking was significantly increased above base-line levels following 3 days of amphetamine administration, at which time 5-HT and 5-HIAA levels were decreased 30 to 40%. NE, DA and DA metabolites were decreased approximately 50 to 90% by this treatment regimen. A third experiment examined the effects of a low dose of amphetamine (3.75 mg/kg), injected more frequently (every 6 hr for 6 days), to approximate the administration pattern in human amphetamine abuse. This treatment produced significant increases in limb flicking and abortive grooming on days 5 and 6 and resulted in 30 to 40% depletions of 5-HT and 5-HIAA. NE, DA and DA metabolites were decreased by approximately 50 to 90%. These data are discussed in relation to a role for serotonin in amphetamine psychosis and schizophrenia.
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PMID:Chronic amphetamine administration to cats: behavioral and neurochemical evidence for decreased central serotonergic function. 50 68

The effects of tandamine, a clinically effective heterocyclic antidepressant, administered either acutely (10 mg/kg i.p.) or chronically (10 mg/kg i.p. daily for 21 days) on biogenic amine uptake and metabolism in the rat were determined and a comparison with desipramine was made. Tandamine, similarly to desipramine, blocked norepinephrine (NE) uptake in rat brain and heart following both acute and chronic administration. No effect of tandamine on dopamine (DA) or serotonin (5-HT) uptake was observed. Both drugs lowered endogenous brain NE when given chronically but not acutely. In contrast, no such effect on brain DA and 5-HT or heart NE was observed. Tandamine, like desipramine, administered chronically prior to an intraventricular injection of 3H-NE, produced increases in the decline of 3H-NE as indicated by decreased 3H-NE with increased levels of 3H-normetanephrine in brain stem of rats, suggesting an increased turnover of NE. No such effect was observed following acute treatment. Both drugs increased the behavioural effects of L-Dopa following and acute oral administration, with tandamine appearing superior to desipramine at the lower dose examined (10 mg/kg). Tandamine was 57--833 times less effective in binding to rat brain muscarinic receptors than desipramine, imipramine, butriptyline and amitriptyline, respectively. Thus, tandamine affects biogenic amine mechanism following either acute or chronic administration in a fashion similar to desipramine, but unlike desipramine, it exhibits relatively little anticholinergic properties, a further indication of the potential use of tandamine in the treatment of human depression, particularly where an increase in drive is desired.
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PMID:Effect of acute and chronic treatment of tandamine, a new heterocyclic antidepressant, on biogenic amine metabolism and related activities. 50 51

The interaction between (--)-cocaine and responses to 5-HT elicited through serotonin receptors on autonomic neurones has been investigated on the rabbit heart and the guinea-pig ileum. Low concentrations of (--)-cocaine or its stereoisomer, (4)-pseudococaine, produced shifts to the right of the 5-HT dose-response curves on heart and ileum with no depression of the maximum responses to electrical stimulation or dimethylphenylpiperazinium remained unaffected. A Schild analysis of data obtained on heart and ileum indicated competitive antagonism of 5-HT by (--)-cocaine. Antagonism of 5-HT by the cocaine isomers cannot be ascribed to local anaesthesia per se since neither lignocaine, tetracaine, benzocaine nor bu tacaine were selective antagonists of 5-HT. Similarly, inhibition of monoamine uptake seems of minimal relevance since desipramine proved only a weak antagonist of 5-HT on the heart and did not influence the 5-HT antagonist potency of (--)-cocaine. Selective blockade of 5-HT neuronal responses is a property shared by several structural analogues of (--)-cocaine and (+)-pseudococaine; nor-(--)-cocaine proved the most potent of these, being active at a concentration of 2 x 10(-8) M. These data indicate that (--)-cocaine and several of its derivatives inhibit 5-HT stimulation of both adrenergic and cholinergic autonomic neurones through competition with the agonist at serotonin receptor sties. Since morphine, the tool normally used to identify responses mediated through neuronal serotonin receptors, acts only at certain "morphine-sensitive" junctions and then, non-discriminately, the cocaine analogues, and particularly nor-(--)-cocaine would seem to offer real advantages as tools for differentiating such responses.
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PMID:Blockade of serotonin receptors on autonomic neurones by (-)-cocaine and some related compounds. 52 45


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