***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: The adrenocorticotropic hormone ( ACTH ) and cortisol responses to apomorphine ( APO ) , a direct acting dopamine ( DA ) agonist , have been reported to be significantly blunted in neuroleptic-free patients with schizophrenia ( SCH ) . This study primarily examined the cortisol , but also the prolactin ( PRL ) and growth hormone ( GH ) , response to APO in patients with SCH compared to normal controls , as well as the relationship between endocrine measures and response to antipsychotic drug treatment . APO , 0.01 mg/kg , or placebo was administered to 51–98 patients with SCH and 15–25 normal controls .  Psychopathology was assessed at the baseline and six weeks after drug treatment . The plasma cortisol response to APO  was markedly blunted in patients with SCH compared to normal controls . Patients who responded to six weeks of treatment with antipsychotic drugs had a higher cortisol response to APO compared to non-responders . The plasma GH , but not PRL , response to APO was blunted in male patients with SCH .  Neither plasma GH nor PRL responses to APO were related to treatment response at six weeks . These results provide further evidence of dopaminergic dysfunction in SCH . Furthermore , the  APO-stimulated cortisol response may be predictive of subsequent clinical response to antipsychotic drug treatment Some investigators have speculated that structural brain alterations observed in some psychiatric patients might be related to increased limbic-hypothalamic-pituitary-adrenal axis ( LHPA ) activity . To explore this hypothesis , we prospect ively studied 166 research volunteers ( 19 patients with research diagnostic criteria ( RDC ) major depression , 9 patients with RDC bipolar depression , 45 patients with RDC schizophrenia , and 94 RDC normal controls ) , examining the relationship between magnetic resonance image-determined ventricular-to-brain ratio ( VBR ) and indices of LHPA axis function ( cerebrospinal fluid ( CSF ) corticotropin-releasing factor ( CRF ) , CSF adrenocorticotropic hormone ( ACTH ) , and 24-hour urinary-free cortisol secretion ) . We observed no significant differences in mean VBR among the three patient groups and the normal control volunteers . Of the indices of LHPA activity , only CSF CRF concentrations distinguished the four subject groups , with CSF CRF being significantly elevated in the more severely depressed major depression patients . Indices of LHPA activity were not significantly correlated with VBR in any of the three patient groups or in the normal volunteers . These preliminary results suggest that VBR is not highly associated with alterations in LHPA activity , at least as determined cross-sectionally . Further longitudinal studies with reference to diagnostic subtypes , severity , symptom profiles , and more specific neuroanatomic regions may allow the elucidation of possible relationships between LHPA pathology and structural brain alterations This study examined the prolactin ( PRL ) , adrenocorticotropin ( ACTH ) and cortisol responses to the direct DA receptor agonist apomorphine ( APO ) and the selective 5HT-releasing agent d-fenfluramine ( d-FEN ) in 20 untreated in patients with DSM-IV schizophrenia and without a history of suicide attempt , compared to 23 hospitalized healthy controls . We hypothesized that different patterns of responsiveness of the DA and 5-HT systems might be associated with specific schizophrenic symptom clusters . A positive correlation was observed between pituitary-adrenal response to APO and d-FEN tests ( i.e. deltaACTH and deltacortisol ) in the overall population and in schizophrenic patients . Pituitary-adrenal response to APO  was lower in patients than in normal controls . Moreover , lower pituitary-adrenal response to  APO  and d-FEN  was associated with increased severity of BPRS thought disturbance score . Lower pituitary-adrenal responses to APO  ( and to a lesser degree to d-FEN ) differentiated paranoid from disorganized schizophrenic patients . Neither PRL suppression to APO , nor PRL stimulation to d-FEN  were altered in schizophrenic patients . Our results suggest that decreased hypothalamic DA receptor activity ( possibly secondary to increased presynaptic DA release ) together with relatively decreased 5-HT tone characterize paranoid SCH , while normal hypothalamic DA receptor activity together with relatively increased 5-HT tone characterize the disorganized SCH subtype In an attempt to define potential immunological dysfunctions in schizophrenia , we determined the production of interleukin-2 ( IL-2 ) , interleukin-4 ( IL-4 ) , interferon-γ ( IFN-γ ) , and soluble IL-2 receptor ( sIL-2R ) in a whole-blood assay after stimulation with phytohemagglutinin ( PHA ) as well as the serum concentrations of sIL-2R . Because CD4+CD45RO+T cells are the main producers of IFN-γ , we determined the percentage of these cells , as well as of pan T , CD4+T , and CD8+T cells , by flow cytometry . A whole-blood count was performed in addition . Two groups of patients were examined , paranoid-type and residual-type schizophrenics . The numbers of both monocytes and neutrophils , but not of lymphocytes , were increased significantly in the schizophrenic sample .  The IFN-γ production of the schizophrenics as a whole group , and of the paranoid patients , was reduced significantly in comparison with the control group ( p≤0.05 ) . The residual patients produced less IFN-γ than the controls , but more than the paranoid patients . The latter differences did not reach statistical significance . The production of IL-4 , which physiologically antagonizes the production of IFN-γ , was not significantly higher in the patient group . No changes in the lymphocyte sub population s were observed . The production of IL-2 showed a trend toward reduction in paranoid patients , but not in residual schizophrenics . The serum sIL-2R levels were elevated slightly in schizophrenics when compared with controls . In order to rule out a possible effect of cortisol on cytokine production , 20 schizophrenic were compared with 20 age- and gendermatched controls . However , neither elevated cortisol levels were detected in the schizophrenic sample , nor significant intercorrelations between cortisol levels and cytokine production , or levels of sIL-2R , respectively . In summary , our data reinforce the possibility of immune dysfunction in schizophrenia and point to the possible relevance of disease subgroups in this respect OBJECTIVES Higher rates of dexamethasone test ( DST ) nonsuppression in schizophrenia have been attributed to depressive symptoms , suicidality and negative symptoms . No study concerning first-episode schizophrenia has yet been published . DESIGN In patients hospitalised for the first time with first-episode schizophrenia the DST has been performed before , at the end of the acute treatment and after one year . At the same time the clinical evaluation with PANSS was performed . A cortisol value > 5 microgram/dl in either of the postdexamethasone sample s indicated nonsuppression of cortisol . RESULTS A total of 56 males were included . 18 % of pts were DST nonsuppressors at medication-free baseline , 5 % and 16 % after acute treatment and after one year respectively . After 1 year 42/56 of patients fulfilled the criteria of remission . The rate of nonsuppression was 21.4 % , 5 % and 16.4 % in remitters and 7 % , 7 % and 14.3 % in nonremitters . Significant differences in the whole group were found between postdexamethasone cortisolemia at discharge on the one h and and on admission and at the one-year follow-up on the other . Significant correlations were observed between postdexamethasone cortisolemia and negative symptoms at the end of acute treatment . MAIN FINDINGS In first-episode schizophrenia the short-term treatment led to a decrease in cortisolemia and rates of nonsuppression and an increase at a one-year follow-up . CONCLUSIONS Rates of DST nonsuppression in schizophrenia including first-episode schizophrenia are influenced by the stage of illness and medication status . The impairment of feedback regulation of cortisol secretion may be related to different biopathogenetic mechanisms depending on the phase of the illness Psychosocial stress is a potent activator of the hypothalamus-pituitary-adrenal ( HPA ) axis . While the physiological mechanisms of HPA axis responses to stress as well as its short and long-term consequences have been extensively examined , less is known why someone elicits an acute neuroendocrine stress response , i.e. what are the psychological processes involved and how are they related to the acute neuroendocrine stress response . To examine this question , a question naire to assess anticipatory cognitive appraisal processes was developed and administered to 81 male healthy subjects in a st and ardized psychosocial stress situation ( Trier social stress test ) .  Cortisol stress responses were assessed with repeated measurement of salivary free cortisol . Hierarchical regression analyses show that anticipatory cognitive appraisal , in contrast to general personality factors and retrospective stress appraisal is an important determinant of the cortisol stress response , explaining up to 35 % of the variance of the salivary cortisol response . The reported results emphasize the importance of psychological stress processing for the underst and ing of psychobiological stress responses . Since stress and its biological consequences have been shown to be associated with the onset and the maintenance of somatic illnesses and psychiatric disorders , psychological processes are prime targets for prevention and intervention Summary Psychotic patients underwent a dexamethasone suppression test ( DST ) , careful diagnostic assessment s at baseline and diagnostic reevaluations after 1 year . The predicted associations between baseline  DST results and diagnosis were much clearer after prospect i ve observation Most prospect i ve studies of HPA axis have found that non-suppressors in the dexamethasone suppression test ( DST ) are more likely to commit suicide during the follow-up . Attempted suicide is a strong clinical predictor of suicide . The aim of this study was to assess the predictive value of DST for suicide in a group of depressed in patients with and without an index suicide attempt . Historical cohort of 382 psychiatric in patients with mood disorder admitted to the department of Psychiatry at the Karolinska University Hospital between 1980 and 2000 were su bmi tted to the DST and followed up for causes of death . During the follow-up ( mean 18 years ) , 36 suicides ( 9.4 % ) occurred , 20 of these were non-suppressors and 16 were suppressors . There was no statistically significant difference in suicide risk between the suppressors and non-suppressors for the sample as a whole . An index suicide attempt predicted suicide . In suicide attempters with mood disorder , the non-suppressor status was significantly associated with suicide indicating that HPA axis hyperactivity is a risk factor for suicide in this group . The dexamethasone suppression test may be a useful predictor within this population BACKGROUND Thyrotropin-releasing hormone ( TRH ) test and Dexamethasone Suppression Test ( DST ) are two neuroendocrine tests that have been extensively used in an attempt to predict treatment response and outcome in schizophrenia . The objectives of this study were to investigate ( 1 ) the relationship between TRH test and DST and various psychiatric symptoms and ( 2 ) the potential value of these tests in prediction of short-term outcome in schizophrenic patients . METHODS TRH test and DST were administered to 58 patients with schizophrenia . All patients were evaluated with a battery of rating scales before neuroendocrine test procedures and at regular intervals for 1 year . Patients were divided into two groups as remitted ( RP ; n = 30 ) and nonremitted patients ( NRP ; n = 28 ) . Baseline results of these two groups were compared with each other and 30 healthy controls . RESULTS Basal levels of total T3 ( T3 T ) and free T3 ( T3F ) were higher in RP group than controls . Basal prolactin ( PRL ) level was higher in RP group , but not in NRP , compared to controls . Basal growth hormone ( GH ) and thyroid-stimulating hormone ( TSH ) levels of NRP were significantly higher than those of RP .  DST nonsuppression was observed at a significantly higher rate in RP than NRP and control group . Blunted TSH response rate in RP group was higher significantly compared to other two groups . CONCLUSIONS The data implicate that higher basal TSH and GH levels may be associated with a poorer treatment response , whereas higher total and free T3 levels , a blunted TSH response to TRH and nonsuppression on the DST may indicate a better response in schizophrenics Pretreatment measures of hypothalamic-pituitary-adrenocortical ( HYPAC ) function in depressed , manic , and healthy normal subjects showed that nonsuppression on the dexamethasone suppression test ( DST ) had less positive predictive value for major diagnostic category and was more frequent in normals ( 8/77 ) than recently reported , although it was yet more frequent in depressed patients ( 35/111 ) . Nonsuppression was common in manics ( 8/16 ) , was similar in unipolar and bipolar depressed patients ( 35 % and 27 % , respectively ) , and did not segregate with melancholic , endogenous , or psychotic depression subtypes . Patterns of post-DST plasma cortisol concentration other than simple escape or nonescape from suppression were 
    Output:
    
In summary , the evidence suggests people with schizophrenia can experience both hyper- and hypo-function of the HPA axis .
It is likely that this contributes to the pattern of poor physical health and premature mortality suffered by people with schizophrenia , in particular the high rates of cardiovascular and metabolic disturbance