13 research outputs found
Zanos et al. reply
Clinical data have demonstrated rapid and sustained antidepressant effects of ketamine, a noncompetitive NMDAR (N-methyl-daspartate receptor) antagonist. Recently, Zanos et al.2 claimed that the ketamine metabolite (2R,6R)-hydroxynorketamine (HNK) is essential for the antidepressant effects of ketamine in mice in an NMDAR-independent manner, although no alternative mechanism was proposed, beyond unspecific activation of AMPAR (α -amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptor). Here we report that (2R,6R)-HNK blocks synaptic NMDARs in a similar manner to its parent compound, and we show that the effects of (2R,6R)-HNK on intracellular signalling are coupled to NMDAR inhibition. These data demonstrate that (2R,6R)-HNK inhibits synaptic NMDARs and subsequently elicits the same signal transduction pathway previously associated with NMDAR inhibition by ketamine
McLean-Harvard International First-Episode Project:two-year stability of DSM-IV diagnoses in 500 first-episode psychotic disorder patients.
OBJECTIVE: Since stability of DSM-IV diagnoses of disorders with psychotic
features requires validation, we evaluated psychotic patients followed
systematically in the McLean-Harvard International First Episode Project.
METHOD: We diagnosed 517 patients hospitalized in a first psychotic illness by
SCID-based criteria at baseline and at 24 months to assess stability of specific
DSM-IV diagnoses.
RESULTS: Among 500 patients (96.7%) completing the study, diagnoses remained
stable in 77.6%, ranking as follows: bipolar I disorder (96.5%) > schizophrenia
(75.0%) > delusional disorder (72.7%) > major depressive disorder (MDD), severe,
with psychotic features (70.1%) > brief psychotic disorder (61.1%) > psychotic
disorder not otherwise specified (NOS) (51.5%) >> schizophreniform disorder
(10.5%). Most changed diagnoses (22.4% of patients) were to schizoaffective
disorder (53.6% of changes in 12.0% of subjects, from psychotic disorder NOS >
schizophrenia > schizophreniform disorder = bipolar I disorder most recent
episode mixed, severe, with psychotic features > MDD, severe, with psychotic
features > delusional disorder > brief psychotic disorder > bipolar I disorder
most recent episode manic, severe, with psychotic features). Second most changed
diagnoses were to bipolar I disorder (25.9% of changes, 5.8% of subjects, from
MDD, severe, with psychotic features > psychotic disorder NOS > brief psychotic
disorder > schizophreniform disorder). Third most changed diagnoses were to
schizophrenia (12.5% of changes, 2.8% of subjects, from schizophreniform disorder
> psychotic disorder NOS > brief psychotic disorder = delusional disorder = MDD,
severe, with psychotic features). These 3 categories accounted for 92.0% of
changes. By logistic regression, diagnostic change was associated with
nonaffective psychosis > auditory hallucinations > youth > male sex > gradual
onset.
CONCLUSIONS: Bipolar I disorder and schizophrenia were more stable diagnoses than
delusional disorder or MDD, severe, with psychotic features, and much more than
brief psychotic disorder, psychotic disorder NOS, or schizophreniform disorder.
Diagnostic changes mainly involved emergence of affective symptoms and were
predicted by several premorbid factors. The findings have implications for
revisions of DSM and ICD