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R S Kahn

Publications and source records attributed to R S Kahn.

156 records · Page 9Linked to original sources

Neuroendocrine evidence for serotonin receptor hypersensitivity in panic disorder.

Normal controls (NC) (n = 15), patients with panic disorder (PD) (n = 13) and patients with major depression (MD) (n = 17) were challenged with a single, oral dose (0.25 mg/kg) of the selective 5HT agonist m-chlorophenyl-piperazine (MCPP) or placebo. Blood samples were assayed for cortisol and MCPP levels every 30 min. The PD group had an augmented cortisol release when compared to the other two groups. Finally, a significant correlation was found across all subjects between clinical anxiety level and cortisol release on MCPP. These data support the hypothesis of 5HT receptor hypersensitivity in PD.

Adult↗

Behavioral indications for serotonin receptor hypersensitivity in panic disorder.

Immediate placebo-corrected behavioral responses to m-chlorophenylpiperazine (MCPP), a selective serotonin agonist, are reported in 11 normal controls, 10 patients with panic disorder, and 10 patients with major depression. Whereas the normal and depressed groups showed no noteworthy behavioral response, panic disorder patients became more anxious, depressed, and hostile, and 60% had panic attacks. These data suggest a hypersensitive postsynaptic serotonin receptor system in some panic disorder patients.

Adult↗

Effect of serotonin uptake inhibitors in anxiety disorders; a double-blind comparison of clomipramine and fluvoxamine.

A double-blind comparative study of clomipramine and fluvoxamine was performed in 50 patients suffering from anxiety disorders (DSM-III). Patients were treated for 6 weeks with either 150 mg of clomipramine or 100 mg of fluvoxamine. The results show that both drugs at the dosages used are equipotent in reducing anxiety symptoms as assessed with the Hamilton Anxiety Scale and the Spielberger State-Trait Anxiety Inventory. Clomipramine differed from fluvoxamine in its efficacy with respect to associated depressive symptomatology in that it had a more pronounced effect on the Self Rating Depression Scale. The results support the hypothesis that brain serotonergic pathways are implicated in the pathophysiology of anxiety disorders, particularly in agoraphobia and panic disorders.

Adult↗

Effect of a serotonin precursor and uptake inhibitor in anxiety disorders; a double-blind comparison of 5-hydroxytryptophan, clomipramine and placebo.

A double-blind placebo-controlled study of 5-HTP and clomipramine was carried out on 45 patients suffering from anxiety disorders (DSM-III). Clomipramine has shown to be effective in that it induced significant improvement on all rating scales as compared to placebo. 5-HTP showed a moderate reduction of the symptomatology on the 90-item symptoms checklist (SCL-90) and the State Scale of the Spielberger State-Trait Anxiety Inventory. Clomipramine and 5-HTP differed in their efficacy in that 5-HTP did not affect the associated depressive symptomatology. The results support the hypothesis that brain serotonergic pathways are involved in the pathogenesis of anxiety disorders, particularly in agoraphobia and panic disorders.

5-Hydroxytryptophan↗

Clinical, biochemical, and hormonal aspects of treatment with Des-tyr1-gamma-endorphin in schizophrenia.

Des-tyr1-gamma-endorphin (DT gamma E) was administered intramuscularly in a dose of 1 mg/day for 10 days to 18 neuroleptic-free schizophrenic patients in a double-blind crossover design. Six patients showed either a slight or no antipsychotic response; seven patients showed a moderate antipsychotic response; and the remaining five patients showed a marked antipsychotic response. DT gamma E led to a decrease of plasma prolactin levels in patients treated with DT gamma E in the first period of experimental treatment as compared to those treated with placebo. Neither plasma levels of growth hormone and cortisol nor cerebrospinal fluid concentrations of homovanillic acid, 5-hydroxyindoleacetic acid, and 3-methoxy-4-hydroxyphenylglycol were affected by DT gamma E. Patients suffering from a hebephrenic or paranoid type of schizophrenia and those presenting relatively fewer negative symptoms were most susceptible to treatment with DT gamma E. These data confirm and extend previous findings that DT gamma E has antipsychotic properties in a number of schizophrenic patients.

Adolescent↗

Non-opiate beta-endorphin fragments and dopamine--I. The neuroleptic-like gamma-endorphin fragments interfere with the behavioural effects elicited by small doses of apomorphine.

In rats, the beta-endorphin fragment, 6-17 (des-enkephalin-gamma-endorphin, DE gamma E), dose-dependently antagonized the reduction of the rate of locomotion and rearing induced by small doses of apomorphine. Structure-activity studies revealed that the active moiety of gamma-endorphin fragments with respect to counteracting apomorphine-induced behavioural changes resides in the fragment 6-17. The influence of DE gamma E appeared to be specific for dopamine systems mediating apomorphine-induced hypomotility, since DE gamma E hardly affected apomorphine-induced stereotypy and amphetamine-induced behavioural changes. These data suggest that DE gamma E acts as a dopamine antagonist selectively, on those dopamine receptor systems which are stimulated by small doses of apomorphine and which may be located presynaptically. In contrast to acute treatment, administration of DE gamma E for 4 days resulted in an enhancement of apomorphine-induced hypomotility. Thus, the receptor systems involved in these effects of apomorphine may become supersensitive upon (sub)chronic treatment with DE gamma E. The significance of the present findings are discussed in relation to the neuroleptic-like and antipsychotic action of gamma-type endorphins.

Animals↗

L-5-hydroxytryptophan in the treatment of anxiety disorders.

Ten outpatients suffering from anxiety states (Anxiety Disorders: DSM-III) were treated with L-5-hydroxytryptophan and carbidopa. A significant reduction in anxiety was observed on three different anxiety scales. It is suggested that 5-HT systems may be involved in the mediation of anxiety.

5-Hydroxytryptophan↗

Denosologization of biological psychiatry or the specificity of 5-HT disturbances in psychiatric disorders.

5-Hydroxytryptamine (5-HT) disorders have been reported to occur in a variety of psychiatric disorders. The situation has been called chaotic, the disturbances non-specific. We reject this viewpoint. 5-HT disturbances are non-specific only from a nosological/categorical viewpoint; they seem rather specific from a functional/dimensional point of view, correlating as they do with particular psychopathological dimensions, i.e. aggression-, anxiety- and possibly mood-disregulation, across diagnosis. The evolution of 5-HT research in psychiatry illustrates the importance of what we have called the functional approach, implying dissection of a given psychopathological syndrome in its component parts, i.e., the psychological dysfunctions, and searching for correlations between biological and psychological dysfunctions. The rigid preoccupation of biological psychiatry with the search for markers of disease entities has hampered progress. The functional approach should be incorporated in biological psychiatry, not as an alternative for the nosological approach but as its complement.

Anxiety Disorders↗