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Biomedical subjects

H M van Praag

Publications and source records attributed to H M van Praag.

At least 55 records · Page 3Linked to original sources
PubMed1993

Correlates of suicide and violence risk in an inpatient population: coping styles and social support.

Forty-six suicidal psychiatric inpatients were compared with 44 nonsuicidal psychiatric inpatients on measures of suicide risk, violence risk, impulsivity, feelings of anger, social support, and eight coping styles. The two groups were similar on demographic variables, but the suicidal patients were higher on the suicide risk scale, the violence risk scale, the impulsivity scale, and feelings of anger. Suicidal patients were significantly less likely to use the coping style of minimization to deal with life problems. A negative correlation was found between the social support measure and both suicide risk and violence risk. Three coping styles were found to correlate negatively with violence risk, but none with suicide risk. Coping styles were found to be a better predictor of violence risk than of suicide risk. It was also found that the more variables included in the predictor equation, the higher the correlation with the risk measures.

Adaptation, Psychological↗
PubMed1993

Headache and cortisol responses to m-chlorophenylpiperazine are highly correlated.

The serotonin receptor agonist m-chlorophenylpiperazine (m-CPP) stimulates the release of cortisol and prolactin, and induces migraine-like headaches. We have studied the neuroendocrine and headache responses to m-CPP in 8 subjects with migraine and 10 normal subjects. Each subject underwent two challenge tests, one with 0.25 mg/kg PO of m-CPP and the other with placebo, administered in a double-blind crossover format. Serial measurements of serum cortisol, prolactin, and m-CPP levels were made at 30-min intervals for 210 min following ingestion of the medication. The incidence and severity of headache was assessed by a structured telephone interview after each test. We confirmed that m-CPP stimulates the release of cortisol and prolactin, and may induce headache, in both migraine subjects and normal controls. The cortisol response as well as ratings of headache severity and duration directly correlated with plasma levels of m-CPP. There were highly significant associations between the cortisol response and both headache severity and duration, independent of m-CPP plasma levels. We did not find statistically significant differences between the migraine and normal subjects in terms of their neuroendocrine or headache responses to m-CPP.

Adult↗
PubMed1993

Anxiety, impulsivity and depressed mood in relation to suicidal and violent behavior.

Many different variables have been associated with suicidal behavior as well as with violent behavior. This study was designed to test a model that attempts to relate such variables to violence and suicide risk. Sixty psychiatric patients were evaluated and divided into suicidal and nonsuicidal groups and then into violent and nonviolent groups. Scores on suicide risk, violence risk, anxiety, anger, impulsivity and mood were then compared between these groups. In a second analysis, scores on suicide risk and violence risk were correlated with all the other variables. Anxiety and impulsivity were found to strongly correlate with suicide risk. Angry and resentful mood correlated with violence risk; trait anxiety correlated negatively with violence risk. The results contribute further insight into the authors' two-stage model of countervailing forces.

Adult↗
PubMed1993

Diagnosis, the rate-limiting factor of biological depression research.

The third edition of the DSM provided a standardized, operationalized classification system of mood disorders. In this paper, the question is raised whether this system is a good starting point for biological depression research. The question is answered in the negative and the reasons why are being discussed. The proposed mood disorders are not properly validated and utterly heterogeneous and overlapping. An etiological axis is wanting and no hypothesis as to the relations between axis I and II diagnoses is required. The comorbidity problem is not satisfactorily resolved. The system leaves no room for a dimensional/functional analysis of mood and personality disorders. The frequent revisions that are only to a small extent based on preconceived research, lead to havoc in the research arena. The DSM III classification is considered to be the single most important factor hampering biological depression research. Ways to remedy the situation are pointed out.

Comorbidity↗
PubMed1993

Suicidal behaviors in adult psychiatric outpatients, I: Description and prevalence.

OBJECTIVE: Because the findings of previous studies of suicidal behaviors in psychiatric outpatients may not necessarily generalize to outpatients with a wide spectrum of psychiatric diagnoses, the authors evaluated the prevalence of suicidal behaviors in a large general psychiatric outpatient clinic whose patients represented a full spectrum of psychiatric illness. METHOD: A total of 651 patients participated in the study between 1987 and 1989. These patients had sought treatment at the outpatient psychiatry department of a private nonprofit hospital. Before being interviewed for treatment, all patients were given a comprehensive self-rating survey packet that included the Harkavy Asnis Suicide Survey and the Hopkins Symptom Checklist-90. The Harkavy Asnis Suicide Survey is a self-report questionnaire that assesses demographic variables, current and past history of suicidal behaviors of the patient as well as family members and peers, and a detailed description of each previous attempt. RESULTS: Fifty-five percent of the patients had a history of suicidal ideation, and 25% reported at least one previous suicide attempt. Approximately half of the suicide attempters reported multiple attempts. The predominant methods of attempt were overdose (53%), jumping (17%), and wrist cutting (17%). Suicidal behavior was prevalent in most diagnostic groups. The rates of suicidal ideation among patients with mood disorders (major depression, dysthymia, and bipolar disorder), adjustment disorders, and alcohol/substance abuse were significantly greater than that of the patients with generalized anxiety disorder. CONCLUSIONS: The authors conclude that suicidal behavior is prevalent among patients who seek treatment in a general outpatient department.

Adjustment Disorders↗
PubMed1992

Serotonin denervation enhances responsiveness of presynaptic dopamine efflux to acute clozapine in nucleus accumbens but not in caudate-putamen.

Clozapine alters mesolimbic dopamine (DA) function but spares nigrostriatal DA function in laboratory animals, but the underlying mechanism is unknown. In the present study, acute intraperitoneal injection of clozapine (5-40 mg/kg) increased extracellular DA levels in nucleus accumbens (Acb) and caudate-putamen (CPu) of awake, freely moving rats as measured by in vivo brain microdialysis, without anatomic selectivity. However, in serotonin (5HT)-denervated rats acute clozapine preferentially enhanced DA levels in Acb as compared to CPu. Since (i) up-regulation of 5HT receptors on DA neurons may result from 5HT denervation, (ii) clozapine has potent anti-5HT action, and (iii) 5HT receptors are more dense in Acb than CPu, these data appear to add additional weight to previous suggestions that a serotonergic mechanism may partly underlie clozapine's mesolimbic selectivity.

3,4-Dihydroxyphenylacetic Acid↗
PubMed1992

Suicide and violence associated with panic attacks.

Several studies have indicated that patients with panic attacks have a higher rate of suicide attempts as well as deaths from suicide. Additionally, several investigators have presented case reports of individuals manifesting suicidal and violent behaviors directly and temporally associated with panic attacks. We report on four additional cases and suggest that these findings may explain, in part, the increased rate of suicidal behavior among patients with panic attacks found by some investigators. Furthermore, these case reports offer preliminary evidence that the relationship between violent behavior and the panic state may be clinically significant and deserving of further elucidation.

Adult↗
PubMed1992

A dose-response study of intravenous m-chlorophenylpiperazine in normal subjects.

A placebo-controlled dose-response study of the direct serotonin receptor agonist m-chlorophenylpiperazine (MCPP), intravenously infused over 90 s in 0.06 and 0.08 mg/kg doses, was conducted in nine normal male subjects. Cortisol, prolactin, MCPP serum levels and behavioral responses were measured over a 210-min period. Both doses caused significant cortisol and prolactin release and were associated with significantly greater behavioral effects as compared to placebo. Though the two doses were associated with different MCPP serum levels, they did not significantly differ in their hormonal and behavioral effects.

Adult↗
PubMed1992

Cortisol response to intramuscular desipramine in patients with major depression and normal control subjects: a replication study.

The authors conducted a double-blind study evaluating the cortisol response to 75 mg of desipramine (DMI), administered intramuscularly to 20 patients with major depressive disorder (MDD) and 20 age- and sex-matched normal control subjects. A blunted placebo-corrected cortisol response to DMI was found in MDD patients in comparison with the normal control subjects. Since the behavioral/side effect and pharmacokinetic profiles of DMI were similar for patients with MDD and normal control subjects, these findings suggest that patients with MDD have an underlying biological insensitivity of the hypothalamic-pituitary-adrenal axis to DMI. It is hypothesized that these findings are consistent with a norepinephrine deficit, an alpha 1-adrenergic receptor insensitivity, or both. Further use of DMI as a neuroendocrine probe for the noradrenergic system is indicated.

Adolescent↗
PubMed1992

Functional interrelationship of serotonin and norepinephrine: cortisol response to MCPP and DMI in patients with panic disorder, patients with depression, and normal control subjects.

The relationship between norepinephrine (NE) and serotonin (5-hydroxytryptamine; 5HT) functioning was explored in a neuroendocrine challenge paradigm. Ten normal control subjects, 17 patients with major depression, and 22 patients with panic disorder volunteered to participate in this study. Each subject received a challenge with meta-chlorophenylpiperazine (MCPP; 0.25 mg/kg, p.o.), a 5HT agonist, and desmethylimipramine (DMI; 75 mg, i.m.), an indirect NE agonist, in randomized order. The peak-minus-baseline cortisol response to MCPP was used as an indicator of 5HT function, and cortisol response at 75 minutes-minus-baseline to DMI was used as an indicator of NE function. The cortisol responses to DMI and MCPP were found to be highly negatively correlated in the total sample, in particular in the patients with major depression and panic disorder. This finding suggests that the functions (or dysfunctions) of the NE and 5HT systems may not be separate as is usually believed, and that the NE and 5HT disturbances observed in major depression and panic disorder may not be independent. Rather, there may be a joint disturbance of NE-5HT in these disorders.

Adult↗
PubMed1992

About the centrality of mood lowering in mood disorders. Plenary Lecture ECNP Congress, Monte Carlo, October 1991.

5-HT disturbances in depression (as exemplified by lowered CSF 5-HIAA) are not syndrome specific but related to components of the depressive syndrome, specifically to increased anxiety and aggression. These 5-HT disturbances are probably core pathogenetic processes not derivative features. I hypothesized that in this subtype of depression, i.e. in "5-HT related depression", the key psychopathological disturbances are dysregulation of anxiety and aggression, while mood lowering is a "by-product". Based on this hypothesis it was predicted that agents which ameliorate anxiety and/or aggression via harmonization of 5-HT ergic transmission will, in addition, exert overall antidepressant effect in "5-HT related depression". The study of the relative "weight" of the various psychopathological components of depression is a basic exercise in understanding the nature of that condition and could, as such, greatly facilitate the goal-directed search for new and innovative antidepressants.

Affect↗
PubMed1992

Panic disorder: a biological perspective.

Panic disorder (PD) was first delineated as a separate diagnostic entity 25 years ago. It is a prevalent disorder that responds well to pharmacological interventions, most notably to antidepressants and benzodiazepines. PD and other psychiatric disorders, such as generalized anxiety disorder and major depression, overlap clinically, but it is unresolved whether they also overlap biologically. Finally, the pathogenesis of PD is still unclear. Theories linking panic to increased sensitivity to CO2 or serotonin are preliminary, while alpha 2-adrenergic dysregulation in panic is still unproven. However, the development of new, selective, receptor agonists and antagonists in combination with imaging techniques may produce some of the answers to the questions raised since.

Humans↗
PubMed1992

High cholesterol levels in patients with panic disorder.

OBJECTIVE: This study was undertaken to help clarify whether the higher cholesterol levels found in patients with panic disorder are a complication of panic disorder only or are associated with any psychiatric disorder. METHOD: The subjects of the study were 30 patients with panic disorder and 30 patients with major depression, diagnosed according to the Structured Interview for DSM-III-R, and 30 normal control subjects. The three groups were matched for sex and age, and none of the subjects had alcohol/drug abuse, abnormal ECGs, or unstable medical conditions. Blood samples were drawn at random times, and serum cholesterol levels were determined. RESULTS: The patients with panic disorder had significantly higher serum cholesterol levels than did the patients with major depression and the normal control subjects. Among the patients with major depression, histories (current or past) of anxiety disorders were associated with significant elevation of serum cholesterol levels. The presence of stable medical conditions was not associated with higher cholesterol levels in any of the three groups of subjects. CONCLUSIONS: Higher cholesterol levels were particularly associated with panic disorder in comparison with major depression. Higher levels of cholesterol in panic disorder are hypothesized to be a result of increased noradrenergic activity, which may be the underlying biological/neurochemical mechanism for symptoms of panic disorder, including anticipatory anxiety.

Adult↗
PubMed1991

The MCPP challenge test in schizophrenia: hormonal and behavioral responses.

In a neuroendocrine challenge paradigm, the present study investigated responses of schizophrenic patients to m-chlorophenylpiperazine (MCPP), a serotonin (5-hydroxytryptamine, 5HT) agonist. In an oral dose of 0.25 mg/kg, MCPP was administered in a placebo-controlled double-blind design to male schizophrenic patients (n = 7) and normal male controls (n = 8). Behavioral (Positive and Negative Syndrome Scale; PANSS) and hormonal (cortisol, prolactin) variables were measured over the subsequent 210 min. The schizophrenic patients experienced an overall exacerbation of psychopathology on MCPP as compared with placebo (p less than 0.05), with specific worsening of PANSS-positive symptoms (p less than 0.025) and PANSS activation (p less than 0.001). In addition, the schizophrenic patients showed significantly lower cortisol (p less than 0.05) and prolactin (p less than 0.05) responses than the normal subjects. The schizophrenic patients had lower peak MCPP blood levels than the normal subjects, although this difference was not statistically significant. The findings are discussed in terms of 5HT receptor(s) sensitivity and the pharmacokinetics of MCPP in schizophrenia.

Adult↗
PubMed1991

Activation of 5-HT3 receptor by 1-phenylbiguanide increases dopamine release in the rat nucleus accumbens.

The serotonin-3 (5-HT3) agonist 1-phenylbiguanide (0.1-1.0 mM in perfusate) caused a robust, dose-dependent enhancement of extracellular dopamine content in nucleus accumbens as measured by in vivo microdialysis. This action was antagonized by co-perfusion of the 5-HT3 antagonists zacopride and GR38032F (1 mM in perfusate). Similar effects were observed in 5-HT-denervated rats. These findings suggest that there is a potent modulation of dopamine (DA) release in the nucleus accumbens mediated via 5-HT3 receptors, which appear to be located presynaptically on DA terminals of the mesolimbic DA pathway.

3,4-Dihydroxyphenylacetic Acid↗
PubMed1991

Serotonin receptor sensitivity and aggression.

This study investigated the relationship between increased serotonin (5-hydroxytryptamine, 5HT) receptor sensitivity and human aggression. A low oral dose of meta-chlorophenylpiperazine (MCPP), a postsynaptic 5HT receptor agonist, was administered in a placebo-controlled design to depressed (n = 22) and panic disorder (n = 20) patients classified with or without signs of outwardly directed aggression, patients with a history of suicide attempts (inwardly directed aggression) (n = 11), and normal controls (n = 19). Hormones under 5HT control were measured at 30-min intervals. Results were as follows: (1) MCPP did not induce or reduce anger, (2) patients with outwardly directed aggression did not have significantly greater MCPP-induced cortisol or prolactin release than did patients without signs of outwardly directed aggression, (3) patients with a history of suicide attempts did not have significantly greater MCPP-induced cortisol or prolactin release than did normal controls, and (4) MCPP-induced hormone release was unrelated to measures of aggression.

Adult↗