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Query: UMLS:C0011570 (depression)
 172,036 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Our study investigated the convergent and discriminant validity of five of Chapman's Schizotypia Scales (i.e., Physical Anhedonia, Revised Social Anhedonia, Perceptual Aberration, Magical Ideation, and Impulsive Nonconformity; L.J. Chapman, J.P. Chapman, & Raulin 1976, 1978; Eckblad & L.J. Chapman, 1983) and Meehl's Schizoidia Scale (Meehl, 1964) within a sample of 50 personality disordered subjects, many of whom possessed schizotypic traits. It was hypothesized in part that all five of the Chapman scales and the Schizoidia Scale would correlate with the schizotypal personality disorder; the Physical Anhedonia and Revised Social Anhedonia Scales would correlate with the schizoid personality disorder, whereas the Magical Ideation and Perceptual Aberration Scales would not; the Physical and Revised Social Anhedonia Scales would not correlate with the avoidant personality disorder; and the Impulsive Nonconformity Scale would correlate with the borderline and antisocial personality disorders. Only the hypotheses concerning the avoidant personality disorder and the Schizoidia Scale were not supported. The findings remained even when the effects of state anxiety and state depression were controlled. Implications of the findings with respect to the validity of the Chapman and Schizoidia Scales and the personality disorders are discussed.
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PMID:The convergent and discriminant validity of the Chapman Scales. 837 97

This study was designed to investigate the predictive validity of a recently described chronic mild-stress-induced anhedonia model of depression. In an intracranial self-stimulation (ICSS) paradigm, rats were allowed to self-stimulate in the ventral tegmental area. Stimulation frequency thresholds for ICSS responses were determined prior to, during, and after a 19-day period of exposure to a variety of mild, intermittent, unpredictable stressors. After nine days of mild stress, stimulation threshold was significantly increased, suggesting a gradual decrease in the rewarding properties of brain stimulation. This anhedonic state lasted throughout the stress period and slowly disappeared over a 10-day period after termination of the stress regimen. This stress-induced increase in ICSS threshold was not observed in rats that were stressed and concomitantly treated with the reversible inhibitor of monoamine oxidase type A (RIMA) moclobemide (20 mg/kg, b.i.d.). In nonstressed animals treated with vehicle or moclobemide, no significant change in ICSS occurred during the course of the experiment. These experimental results reinforce the value of this animal model with respect to its predictive and construct validity.
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PMID:Effects of moclobemide, a new generation reversible Mao-A inhibitor, in a novel animal model of depression. 837 9

The Flinders Sensitive Line (FSL) rat, selectively bred for increased responses to the anticholinesterase DFP, was originally proposed as an animal model of depression because, like depressed humans, it is supersensitive to the behavioral and hormonal effects of cholinergic (muscarinic) agonists. The present review critically examines earlier and recent data collected on FSL rats to assess whether the model has good face, construct and/or predictive validity. With respect to face validity, FSL rats resemble depressed humans, at least superficially, in that they demonstrate: (a) reduced locomotor activity, (b) reduced body weight, (c) increased REM sleep, and (d) cognitive (learning) difficulties. So far, studies designed to assess the presence of anhedonia, a cardinal symptom of melancholic depression, have been inconclusive, but there are trends for the FSL rats to be more anhedonic than their control counterparts, the Flinders Resistant Line (FRL) rats, when exposed to chronic mild stress. Thus, FSL rats fulfill the criterion of face validity. Because FSL rats also are more sensitive to cholinergic agonists and have phase advanced circadian rhythms, they meet the criteria for the cholinergic and circadian rhythm models of depression and, therefore, have good construct validity. A key behavioral symptom exhibited by the FSL rat is demonstration of an exaggerated immobility when exposed to stressors such as foot shock and forced swimming. This behavioral abnormality has been normalized by a number of well-recognized antidepressant drugs such as imipramine and desipramine, as well as newer generation antidepressants with promising clinical effects such as sertraline and rolipram. However, several treatments that have not been routinely used to treat depression (lithium, exposure to bright light, the anticholinesterase DFP) have been ineffective in reversing the exaggerated immobility. Thus, the evidence in the present review indicates that the FSL rat model of depression fulfills the criteria of face, construct, and predictive validities.
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PMID:The Flinders sensitive line rats: a genetic animal model of depression. 845 16

Withdrawal from chronic use of psychostimulant drugs in humans induces a clinical syndrome characterized by fatigue, psychomotor depression, anhedonia, and disturbances of sleep. Spontaneous locomotor activity and catalepsy were assessed in rats during withdrawal from a schedule of intravenous self-administration of high doses of amphetamine. At 2 and 4 days after cessation of amphetamine self-administration, rats showed a state of psychomotor retardation as measured by reduction of locomotor activity and increased catalepsy. In search of a possible pharmacologic means of intervention for such behavioral changes, the effect of repeated treatment with the nonaddictive ergot derivative lisuride during the withdrawal phase was evaluated. At a dose devoid of any effects on locomotor activity, lisuride completely prevented the reduction in locomotor activity and the increase in catalepsy produced by amphetamine withdrawal. These results suggest the need for further studies on lisuride as a possible novel treatment during withdrawal from psychostimulant drugs in humans.
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PMID:Lisuride reduces psychomotor retardation during withdrawal from chronic intravenous amphetamine self-administration in rats. 850 48

A study on 55 subjects who meet Spitzer's research Diagnosis Criteria of primary major depressive disorder and 54 healthy subjects has been conducted to explore anhedonia. The two groups were matched concerning the socio-demographic variables (sex, age, education level). Anhedonia was rated using the Physical Anhedonia Scale (PAS) and a physical sub-scale (FCPCS-PP) extracted from the Fawcett Clark pleasure scale. The severity of depression was rated using the Bech HDRS (Hamilton Depression Rating Scale) subscale for global severity. The results have shown that the major depressives are significantly more anhedonic than controls. The PAS mean score of depressives (m = 24.45, sd = 9.22) was significantly higher than the meaning score of normals (m = 16.9, sd = 7.13) (t = 4.7, df = 107, p = 0.0001). The FCPCS-PP mean score of depressives (m = 81, sd = 15) was significantly lower than the mean score of normals (m = 90.6, sd = 7.3) (t = 4.2, df = 107, p = 0.0001). The Pearson correlation coefficients between the anhedonia scales (PAS and FCPCS-PP) and the Bech HDRS were not statistically significant. Anhedonia in major depression seems to be independent of the depression intensity. The distribution of the PAS and the FCPCS-PP scores have been studied in the major depressive group using a test of normality (chi 2 analysis). The results have shown for each scale a normal distribution. Our results do not support the hypothesis of the existence of a severely anhedonic sub-group of major depressives.
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PMID:[Anhedonia in major depression. Comparison of 55 depressed patients with 54 healthy probands]. 852 65

Flinders Sensitive Line (FSL) rats have been proposed as an animal model of depression because they resemble depressed humans in that they have elevated REM sleep, reduced activity, and increased immobility and anhedonia after exposure to stressors. The present paper reviews experiments on the drug treatment of FSL and control Flinders Resistant Line (FRL) rats related to their utility as an animal model of depression, and presents new information. FSL rats exhibited exaggerated immobility in the forced swim test which is counteracted by the tricyclic antidepressants imipramine and desipramine and the serotonin reuptake blocker sertraline; the low immobility exhibited by the FRL rats is generally unaffected by these compounds. In contrast to these "therapeutic" effects of well recognized antidepressants, lithium and bright light treatment did not alter the exaggerated immobility of FSL rats. Novel data indicated that neither FSL nor FRL rats exhibited alterations in swim test immobility following chronic administration of the psychomotor stimulant amphetamine (2 mg/kg) and the anticholinergic scopolamine (2 mg/kg), which typically reduce immobility after acute administration. However, it was found that the calcium channel blockers verapamil (5 and 15 mg/kg) and nicardipine (10 mg/kg) did reduce the exaggerated immobility in FSL rats following chronic administration, suggesting that these compounds need to be evaluated further in humans. Previous studies have indicated no differences between FSL and FRL rats evaluated in the elevated plus maze, either at baseline or after the administration of diazepam, suggesting that the FSL rat may not differ from controls in anxiety-related behavior. Another recently published study showed that the FSL rat also did not differ from normal Sprague-Dawley rats in startle tests, indicating that the FSL rats do not exhibit behaviors shown in animal models of schizophrenia. These findings confirm the utility of FSL rats as an animal model of depression because the FSL rats do not appear to exhibit behaviors analogous to anxiety or schizophrenia and because they respond "therapeutically" to antidepressants and not psychomotor stimulants.
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PMID:Administration of antidepressants, diazepam and psychomotor stimulants further confirms the utility of Flinders Sensitive Line rats as an animal model of depression. 853 39

A depression-like state was induced in Wistar rats by chronic (3-week) exposure to very mild, unpredictable stress, which led to diminished food consumption and diminished preference for sweet drinks (anhedonia). Anhedonia was then abolished by 5 weeks of daily administration of imipramine to the continually stressed animals. One day after the last drug injection and stressful event, a statistically significant decrease in the proliferative activity of splenocytes to Con A stimulation in vitro was observed in those animals. Eight weeks of stress (without antidepressant therapy) affected likewise, but in a less potent and non-significant manner, the activity of splenocytes. Administration of imipramine alone for a period of 5 weeks did not modify the activity of these cells.
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PMID:The effect of chronic treatment with imipramine on the immunoreactivity of animals subjected to a chronic mild stress model of depression. 855 22

Whereas the instability of positive symptoms over time is well recognized, the instability of negative symptoms is still debated. This controversy could be due to the fact that different negative symptoms have been studied in different phases of schizophrenia. We, therefore, hypothesized that some negative symptoms would improve whereas others would remain perfectly stable during the remission of the acute phase of illness. We further hypothesized that the changes in these negative symptoms would be linked to changes in other domains such as extrapyramidal, depressive and positive symptomatology. A broadly defined sample of schizophrenic patients was evaluated at admission and discharge of the hospital with the Scale for the Assessment of Negative Symptoms (SANS) and the Scale for the Assessment of Positive Symptoms (SAPS), the Montgomery and Asberg Depression Rating Scale (MADRS) and the Extrapyramidal Symptoms Rating Scale (ESRS). Doses of antipsychotic medications were converted into chlorpromazine-equivalents. Fifty-seven patients (mean age 40.3 years old) were included in the sample and followed-up during their hospitalization. All the sub-scores of the SANS-SAPS decreased significantly but 4 items of the SANS belonging to the affective flattening subscale (unchanging facial expression, decreased spontaneous movements, paucity of expressive gestures and lack of vocal inflections) and one item belonging to the alogia subscale (poverty of speech) did not vary significantly, showing the necessity of taking into account the individual items of the SANS rather than the subscale scores to evaluate the course of negative symptoms. Changes in all the SANS subscores except the alogia subscore were associated with variations in scores of other scales. The change in attentional subscores was positively correlated to the change in the positive formal thought disorder subscores, probably because both belong to the same syndrome. The change in affective flattening subscores was associated with changes in depressive and akinetic scores and 28% of the variance of the change in the affective flattening subscores was explained by the change in the MADRS scores. Changes in avolition-apathy and anhedonia subscores were also associated with changes in MADRS scores but not with the change in akinesia scores.
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PMID:Negative symptoms in schizophrenia: their evolution during an acute phase. 856 93

Antidepressant properties of 5-HT1A receptor ligands (the full agonist 8-OH-DPAT, the partial agonists ipsapirone and buspirone, and the selective antagonist WAY 100135) were studied in a chronic mild stress model of depression. In this model, rats subjected to a variety of mild stressors for a prolonged period of time show a substantial decrease in the consumption of a 1% sucrose solution (anhedonia), an effect being sensitive to repeated treatment with antidepressant drugs. In the present study we found that the stress-induced deficit in the sucrose intake was gradually reversed by chronic (3-5 weeks) administration of buspirone (2.5 and 5 mg/kg, i.p., b.i.d.) or WAY 100135 (10 mg/kg, s.c., b.i.d.), but not 8-OH-DPAT (0.5 mg/kg, s.c., b.i.d.) or ipsapirone (5 mg/kg i.p., b.i.d.). The magnitude of the effect of buspirone and WAY 100135 was comparable to that observed following similar administration of the antidepressant drugs imipramine (10 mg/kg i.p.) or citalopram (10 mg/kg i.p.). Increases in the sucrose intake following chronic treatment with buspirone, WAY 100135, imipramine and citalopram were specific to the stressed animals; the behaviour of control non-stressed animals was unchanged by any drug. These results suggest that buspirone and WAY 100135 may have antidepressant properties. Possible links between the anti-anhedonic effect of these drugs and their interaction with 5-HT1A receptors and/or the dopamine system are discussed.
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PMID:The effect of 5-HT1A receptor ligands in a chronic mild stress model of depression. 857 28

During the last decades, the term "anhedonia", conceptualized as a incapacity to experience pleasure, have become associated with conditions as different as schizophrenia and depression. This paper deals with the conceptual and historial frames in which anhedonia was first constructed, and shows that the sources for the current fuzziness of this concept include neglect of the fact that anhedonia is conceptually parasitical upon the notion of pleasure, that it has been rather superficially conceptualized as the reduction or abolition in a "putative" function which itself is unlikely to be unitary in nature, and that it has never been quite specified whether the mechanism concerns a deficit in brain signal or not.
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PMID:[Historical review of the concept of anhedonia]. 860 57


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