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The comorbidity of borderline personality disorder and other DSM-III-R axis II personality disorders.

OBJECTIVE: This study examines the comorbidity of DSM-III-R borderline personality disorder and the other axis II personality disorders. The extent and direction of overlap provides a measure of the clarity of its diagnostic boundaries and descriptive validity. METHOD: In 110 outpatients without concurrent major axis I conditions, axis II diagnoses were assessed in semistructured format and all DSM-III-R personality disorder criteria were rated. Multiple diagnoses were recorded. RESULTS: Twenty-two patients (20%) met criteria for borderline personality disorder; 18 (82%) had at least one additional personality disorder diagnosis. Using measures of frequencies and intercorrelation coefficients, the authors found that overlap was extensive and not confined to any one of the three designated axis II clusters. Factor analysis revealed 1) a group containing borderline personality disorder with paranoid, histrionic, narcissistic, antisocial, and passive-aggressive personality disorders and 2) another grouping of schizoid, schizotypal, avoidant, obsessive-compulsive, and self-defeating personality disorders. CONCLUSIONS: Borderline personality disorder appears to constitute a broad, heterogeneous category with unclear boundaries that embraces a general personality disorder concept. Both further refinement of the borderline personality disorder construct and investigation into alternative models to the DSM-III-R axis II classification system are suggested.

Adolescent↗

Revising and assessing axis II, Part II: toward an empirically based and clinically useful classification of personality disorders.

OBJECTIVE: The DSM-IV classification of personality disorders has not proven satisfying to either researchers or clinicians. Incremental changes to categories and criteria using structured interviews may no longer be useful in attempting to refine axis II. An alternative approach that quantifies clinical observation may prove useful in developing a clinically rich, useful, empirically grounded classification of personality pathology. METHOD: A total of 496 experienced psychiatrists and psychologists used the Shedler-Westen Assessment Procedure-200 (SWAP-200) to describe current patients diagnosed with axis II personality disorders. The SWAP-200 is an assessment tool that allows clinicians to provide detailed, clinically rich descriptions of patients in a systematic and quantifiable form. A statistical technique, Q-analysis, was used to identify naturally occurring groupings of patients with personality disorders, based on shared psychological features. The resulting groupings represent an empirically derived personality disorder taxonomy. RESULTS: The analysis found 11 naturally occurring diagnostic categories, some of which resembled current axis II categories and some of which did not. The findings suggest that axis II falls short in its attempt to "carve nature at the joints": In some cases it puts patients who are psychologically dissimilar in the same diagnostic category, and in others it makes diagnostic distinctions where none likely exist. It also fails to recognize a large category of patients best characterized as having a dysphoric personality constellation. The empirically derived classification system appears to be more faithful to the clinical data and to avoid many problems inherent in the current axis II taxonomy. CONCLUSIONS: The approach presented here may be helpful in refining the existing taxonomy of personality disorders and moving toward a system of classification that lies on a firmer clinical and empirical foundation. In addition, it can help to bridge the gap that often exists between research and clinical approaches to personality pathology.

Factor Analysis, Statistical↗

Reliability and validity of DSM-IV axis V.

OBJECTIVE: The authors investigated the reliability and convergent and discriminant validity of the DSM-IV Global Assessment of Functioning Scale and two experimental DSM-IV axis V global rating scales, the Global Assessment of Relational Functioning Scale and the Social and Occupational Functioning Assessment Scale. METHOD: Forty-four patients admitted to a university-based outpatient community clinic were rated by trained clinicians on the three DSM-IV axis V scales. Patients also completed self-report measures of DSM-IV symptoms as well as measures of relational, social, and occupational functioning. RESULTS: The Global Assessment of Functioning Scale, Global Assessment of Relational Functioning Scale, and Social and Occupational Functioning Assessment Scale all exhibited very high levels of interrater reliability. Factor analysis revealed that the Global Assessment of Relational Functioning Scale and the Social and Occupational Functioning Assessment Scale are each more related to the Global Assessment of Functioning Scale individually than they are to each other. The Global Assessment of Functioning Scale was significantly related to concurrent patient responses on the SCL-90-R global severity index. The Social and Occupational Functioning Assessment Scale was significantly related to concurrent patient responses on the SCL-90-R global severity index and to a greater degree with both the Social Adjustment Scale global score and the Inventory of Interpersonal Problems total score. Although the Global Assessment of Relational Functioning Scale was not significantly related to any of the three self-report measures, it was related to the presence of clinician-rated axis II pathology. CONCLUSIONS: The three axis V scales can be scored reliably. The Global Assessment of Relational Functioning Scale and the Social and Occupational Functioning Assessment Scale evaluate different constructs. These findings support the validity of the Global Assessment of Functioning Scale as a scale of global psychopathology; the Social and Occupational Functioning Assessment Scale as a measure of problems in social, occupational, and interpersonal functioning; and the Global Assessment of Relational Functioning Scale as an index of personality pathology. The authors discuss further refinement and use of the three axis V measures in treatment research.

Adult↗

Personality diagnoses in adolescence: DSM-IV axis II diagnoses and an empirically derived alternative.

OBJECTIVE: The study of personality pathology in adolescence is in its infancy. This article examined the applicability and limits of DSM-IV axis II personality disorder diagnoses in adolescents, assessed the validity of a method for assessing adolescent personality pathology, and began to develop an empirically grounded classification. METHOD: A total of 296 randomly selected clinicians described a patient age 14-18 in treatment for maladaptive personality patterns using axis II ratings scales and the Shedler-Westen Assessment Procedure-200 for Adolescents (SWAP-200-A), a Q-sort instrument for assessing adolescent personality pathology. After examining the nature and frequency of axis II disorders in the sample, the authors used Q-factor analysis to identify naturally occurring groupings of patients on the basis of shared personality features. RESULTS: Axis II diagnoses in adolescents resembled those in adults, although application of DSM-IV criteria appeared to overdiagnose antisocial and avoidant personality disorder in adolescents. Q analysis with the SWAP-200-A isolated five personality disorders (antisocial-psychopathic, emotionally dysregulated, avoidant-constricted, narcissistic, and histrionic) and one personality style. Patients' dimensional scores on each diagnostic prototype showed predictable associations with ratings of current axis II disorders, measures of adaptive functioning, and symptoms assessed with the Child Behavior Checklist. CONCLUSIONS: With some exceptions, personality pathology in adolescence resembles that in adults and is diagnosable in adolescents ages 14-18. Categories and criteria developed for adults may not be the optimal way of diagnosing adolescents. Data from samples of adolescents may prove useful in developing an empirically and clinically grounded classification of personality pathology in adolescents.

Adolescent↗

Using the axis V scale to evaluate therapeutic outcome of psychiatric treatment.

This study examined whether the Axis V scale of DSM-III was a useful instrument for coding and evaluating psychiatric patients' response to treatment. It compared outpatients' functional responses to treatment, measured by the Axis V scale used to assess current functioning, with their symptomatic changes. It found that the Axis V scale provided a different dimension of patients' outcome than the symptomatic one. Overall, only 19% of the patients were rated on Axis V as improved functionally, at discharge, as compared to 55% rated as improved symptomatically. However, as outpatients completed more treatment sessions, increasingly larger percentages were rated as improved on the Axis V scale, ranging from 8.5% improved functionally after completing 1-5 sessions to 44.5% improved after 41+ sessions. Symptomatic ratings plateaued after 6-10 sessions, with 80% of the patients being rated as improved symptomatically after completing treatment, no matter how many more treatment sessions they received before discharge. The report discusses the implications of these findings for assessment of psychiatric patients' treatment needs, goals of their treatment programs, and evaluation of treatment outcomes.

Ambulatory Care↗

Helical axis errors affect computer-generated occlusal contacts.

A helical axis describing mandibular motion can be calculated from two distinct positions of the mandible; however, as these positions come closer together, calculation errors increase. This study investigated the effects of errors in the calculated helical axis on simulated mandibular motion by the measurement of changes in occlusal contacts. A standard helical axis was calculated from a simulated lateral movement. A series of digital interocclusal records from centric to a 5 degree mandibular rotation about the standard helical axis was created. Digital dental cast models were aligned to the interocclusal records. Helical axis parameters and occlusal contacts calculated with the use of the aligned digital models were compared with those of the standard. Helical axes calculated from mandibular positions separated by 1.5 degrees to 5.0 degrees yielded equivalent occlusal contacts. Qualitatively, contacts for helical axes calculated from jaw rotations of 0.7 degrees or larger were nearly identical to those of the standard.

Computer Simulation↗

Alteration of the hypothalamic-pituitary-gonadal axis in estrogen- and androgen-treated adult male leopard frog, Rana pipiens.

BACKGROUND: Gonadal steroids, in particular 5 alpha-dihydrotestosterone (DHT) and 17 beta-estradiol (E2), have been shown to feed back on the hypothalamic-pituitary-gonadal (HPG) axis of the ranid frog. However, questions still remain on how DHT and E2 impact two of the less-studied components of the ranid HPG axis, the hypothalamus and the gonad, and if the feedback effects are consistently negative. Thus, the goal of the study was to examine the effects of DHT and E2 upon the HPG axis of the gonadally-intact, sexually mature male leopard frogs, Rana pipiens. METHODS: R. pipiens were implanted with silastic capsules containing either cholesterol (Ch, a control), DHT, or E2 for 10 or 30 days. At each time point, steroid-induced changes in hypothalamic GnRH and pituitary LH concentrations, circulating luteinizing hormone (LH), and testicular histology were examined. RESULTS: Frogs implanted with DHT or E2 for 10 days did not show significant alterations in the HPG axis. In contrast, frogs implanted with hormones for 30 days had significantly lower circulating LH (for both DHT and E2), decreased pituitary LH concentration (for E2 only), and disrupted spermatogenesis (for both DHT and E2). The disruption of spermatogenesis was qualitatively similar between DHT and E2, although the effects of E2 were consistently more potent. In both DHT and E2-treated animals, a marked loss of all pre-meiotic germ cells was observed, although the loss of secondary spermatogonia appeared to be the primary cause of disrupted spermatogenesis. Unexpectedly, the presence of post-meiotic germ cells was either unaffected or enhanced by DHT or E2 treatment. CONCLUSIONS: Overall, these results showed that both DHT and E2 inhibited circulating LH and disrupted spermatogenesis progressively in a time-dependent manner, with the longer duration of treatment producing the more pronounced effects. Further, the feedback effects exerted by both steroid hormones upon the HPG axis were largely negative, although the possibility exists for a stimulatory effect upon the post-meiotic germ cells.

Animals↗

The reliability and validity of the proposed axis V (disabilities) of ICD-10.

BACKGROUND: The purpose of this study was to examine the reliability and validity of the newly proposed axis V (disabilities) of ICD-10. METHOD: Eighty-six acutely ill men and women were prospectively recruited from the Al Ain psychiatric units, UAE. Both versions of ICD-10, the Clinical Descriptions and Diagnostic Guidelines and the Diagnostic Criteria for Research (DCR) were used for coding axis I psychiatric diagnosis and its grade of severity; the WHO Disability Assessment Schedule was used to assess disabilities. RESULTS: Inter-rater reliability of the DAS items ranged from moderate to good, and axis V ratings correctly predicted 84% of the observed classification on axis I. CONCLUSION: Axis V is a valid measure of disabilities, but is limited by its modest reliability.

Activities of Daily Living↗

The hypothalamic-pituitary-adrenal axis activity in obesity and the metabolic syndrome.

A hypothetical role of glucocorticoids in human obesity has been suggested since the abdominal obesity phenotype and syndromes of endogenous or exogenous hypercortisolism share several clinical, metabolic, and cardiovascular similarities. An emerging body of evidence indicates that both neuroendocrine dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis as well as peripheral alterations of cortisol metabolism may play a role in the pathophysiology of abdominal obesity. Major alterations of the HPA axis in vivo may be identified in different ways. They include evaluation of hormone concentrations: (a) in basal conditions, in blood, urine, or saliva samples; (b) during dynamic studies following stimulation with different neuropeptides or psychological stress challenges, or suppression with inhibiting agents of the HPA axis at different levels; and (c) after mixed meals or meals containing different nutrient compositions. In addition, alteration of peripheral cortisol metabolism can be detected by direct measurement of cortisol metabolites in urine, although this is a matter of more complex investigation. Alterations of the HPA axis in abdominal obesity are associated with insulin resistance, which suggests a direct responsibility of these hormonal alterations in the susceptibility of affected patients to develop both metabolic and cardiovascular diseases. According to available data, no single marker probably has the power to detect subtle alterations of the HPA axis in conditions, such as the abdominal obesity and the metabolic syndrome. On the contrary, they indicate the need for multiple parameters. At present, evaluation of urinary free cortisol, particularly during the night-time, and salivary-free cortisol appear to be promising for these purposes, whereas dynamic tests should be reserved for specific clinical settings, involving well-characterized patients.

Glucocorticoids↗

Correlations between hypothalamus-pituitary-adrenal axis parameters depend on age and learning capacity.

Glucocorticoid hormones are released after activation of the hypothalamus-pituitary-adrenal (HPA) axis and in the brain can modulate synaptic plasticity and memory formation. Clear individual differences in spatial learning and memory in the water maze allowed classification of groups of young (3 months) and aged (24 months) male Wistar rats as superior and inferior learners. We tested 1) whether measures of HPA activity are associated with cognitive functions and aging and 2) whether correlations of these measures depend on age and learning performance. Basal ACTH, but not corticosterone, was increased in aged rats, with the stress-induced ACTH response exaggerated in aged-inferior learners. Aged-superior learners had lower expression of glucocorticoid receptor and CRH mRNA in the parvocellular paraventricular nucleus of the hypothalamus compared with all other groups. Hippocampal mineralocorticoid receptor and glucocorticoid receptor mRNAs differed modestly between groups, but steroid receptor coactivator and heat-shock-protein 90 mRNAs were not different. Strikingly, correlations between HPA axis markers were dependent on grouping animals according to learning performance or age. CRH mRNA correlated with ACTH only in aged animals. Parvocellular arginine vasopressin mRNA was negatively correlated to basal corticosterone, except in aged-inferior learners. Corticosteroid receptor mRNA expression showed a number of correlations with other HPA axis regulators specifically in superior learners. In summary, the relationships between HPA axis markers differ for subgroups of animals. These distinct interdependencies may reflect adjusted set-points of the HPA axis, resulting in adaptation (or maladaptation) to the environment and, possibly, an age-independent determination of learning ability.

Adrenal Glands↗

Hypoactivity of the hypothalamo-pituitary-adrenocortical axis during recovery from chronic variable stress.

Chronic stress induces both functional and structural adaptations within the hypothalamo-pituitary-adrenocortical (HPA) axis, suggestive of long-term alterations in neuroendocrine reactivity to subsequent stressors. We hypothesized that prior chronic stress would produce persistent enhancement of HPA axis reactivity to novel stressors. Adult male rats were exposed to chronic variable stress (CVS) for 1 wk and allowed to recover. Plasma ACTH and corticosterone levels were measured in control or CVS rats exposed to novel psychogenic (novel environment or restraint) or systemic (hypoxia) stressors at 16 h, 4 d, 7 d, or 30 d after CVS cessation. Plasma ACTH and corticosterone responses to psychogenic stressors were attenuated at 4 d (novel environment and restraint) and 7 d (novel environment only) recovery from CVS, whereas hormonal responses to the systemic stressor were largely unaffected by CVS. CRH mRNA expression was up-regulated in the paraventricular nucleus of the hypothalamus (PVN) at 16 h after cessation of CVS, but no other alterations in PVN CRH or arginine vasopressin mRNA expression were observed. Thus, in contrast to our hypothesis, reductions of HPA axis sensitivity to psychogenic stressors manifested at delayed recovery time points after CVS. The capacity of the HPA axis to respond to a systemic stressor appeared largely intact during recovery from CVS. These data suggest that chronic stress selectively targets brain circuits responsible for integration of psychogenic stimuli, resulting in decreased HPA axis responsiveness, possibly mediated in part by transitory alterations in PVN CRH expression.

Adaptation, Physiological↗

Angiotensin II inhibition reduces stress sensitivity of hypothalamo-pituitary-adrenal axis in spontaneously hypertensive rats.

Angiotensin II type 1 (AT(1)) receptors are expressed within organs of the hypothalamo-pituitary-adrenal (HPA) axis and seem to be important for its stress responsiveness. Secretion of CRH, ACTH, and corticosterone (CORT) is increased by stimulation of AT(1) receptors. In the present study, we tested whether a blockade of the angiotensin II system attenuates the HPA axis reactivity in spontaneously hypertensive rats. Spontaneously hypertensive rats were treated with candesartan (2 mg/kg), ramipril (1 mg/kg), or mibefradil (12 mg/kg) for 5 wk. In addition to baseline levels, CORT and ACTH responses to injection of CRH (100 microg/kg) were monitored over 4 h. mRNA of CRH, proopiomelanocortin, AT(1A), AT(1B), and AT(2) receptors was quantified by real-time PCR. All treatments induced equivalent reductions of blood pressure and had no effect on baseline levels of CORT and ACTH. However, both candesartan and ramipril significantly reduced CRH-stimulated plasma levels of ACTH (-26 and -15%) and CORT (-36 and -18%) and lowered hypothalamic CRH mRNA (-25 and -29%). Mibefradil did not affect any of these parameters. Gene expression of AT(1A), AT(1B), and AT(2) receptors within the HPA axis was not altered by any drug. We show for the first time that antihypertensive treatment by inhibition of AT(1) receptors or angiotensin-converting enzyme attenuates HPA axis reactivity independently of blood pressure reduction. This action is solely evident after CRH stimulation but not under baseline conditions. Both a reduced pituitary sensitivity to CRH and a down-regulation of hypothalamic CRH expression have the potential to reduce HPA axis activity during chronic AT(1) blockade or angiotensin-converting enzyme inhibition.

Angiotensin II↗

The muscarinic cholinergic agonist arecoline stimulates the rat hypothalamic-pituitary-adrenal axis through a centrally-mediated corticotropin-releasing hormone-dependent mechanism.

Several lines of experimental evidence suggest that acetylcholine and other cholinergic agonists are excitatory to the hypothalamic-pituitary-adrenal (HPA) axis. To examine the site on the HPA axis that is stimulated by cholinergic agents, we evaluated the in vivo and in vitro effects of the muscarinic cholinergic agonist arecoline in intact and pituitary stalk-transected rats as well as on isolated rat hypothalami, dispersed anterior pituicytes, and adrenocortical cells in culture. Arecoline, injected iv to catheterized, freely moving male Sprague-Dawley rats, stimulated plasma ACTH and corticosterone release in a dose-dependent fashion. The muscarinic cholinergic antagonist atropine significantly blunted the ACTH response to arecoline. Pituitary stalk transection led to diminished plasma ACTH and corticosterone responses to arecoline. Similarly, previous administration of anti-CRH serum significantly blunted these responses. These findings suggest that arecoline stimulates the HPA axis centrally, mainly via secretion of CRH. This hypothesis was confirmed by the dose-dependent ability of arecoline to cause hypothalamic CRH secretion in vitro, an effect antagonized by atropine, and its failure to elicit ACTH and corticosterone secretion by dispersed anterior pituicytes and adrenocortical cells in culture, respectively. These data suggest that the muscarinic cholinergic agonist arecoline stimulates the HPA axis in the rat and that this effect is mediated mainly by the release of endogenous CRH. Arecoline, therefore, appears to be a compound suitable to selectively evaluate the responsiveness of the central component of the HPA axis.

Adrenal Cortex↗

Free fatty acids activate the hypothalamic-pituitary-adrenocortical axis in rats.

Intravenous administration of Intralipid 10% increases blood levels of essential free fatty acids. In rats and man, this is associated with an inhibition of GH secretion from the anterior pituitary. Because GH is lipolytic, the inhibition of its secretion may represent a negative feedback action of the fats on pituitary sensitivity to GH-releasing hormone. Since corticosterone, the final secretory product of the rat hypothalamic-pituitary-adrenocortical (HPA) axis, is also lipolytic, we tested the hypothesis that FFA would inhibit the HPA axis. Rats were cannulated via the jugular vein and infused with different doses of heparin-Intralipid 10% or heparin-saline; sequential blood samples were obtained and analyzed for ACTH, corticosterone, FFA, and glucose. Intralipid at 2.85 ml/kg increased plasma FFA to over 3 meq/liter by 15 min, with a return to baseline by 60-90 min. There was no effect of the infusion on plasma osmolarity or pH. At 60 min, plasma ACTH levels were significantly elevated to over 1500 pg/ml in Intralipid-infused rats, but were unchanged in saline controls. This dose of Intralipid increased corticosterone levels by nearly 20-fold at 120 min. At 180 min, corticosterone levels were still significantly greater than those in saline controls. Lower doses of Intralipid also significantly elevated both FFA and corticosterone levels, but by 180 min, levels of both were similar to those in controls. The effects of Intralipid on corticosterone secretion could not be attributed to the presence of glycerol in the suspension, since glycerol infusions had no significant effect on steroid levels compared to those in saline controls. In dexamethasone-pretreated rats, there was no significant rise in plasma corticosterone after either of two Intralipid doses, suggesting that the action of Intralipid was at a site within the HPA axis above the adrenal gland. This finding also suggested that the high steroid levels after Intralipid treatment were not due to interference with the corticosterone RIA. This was verified by the finding that there was no increase in plasma immunoreactive corticosterone after Intralipid infusion into adrenalectomized rats. Intralipid also caused an increase in plasma glucose levels that was first significant at 60 min and declined to baseline by 180 min, possibly reflecting increased autonomic activity or peripheral insensitivity to insulin. The results suggest that high circulating FFA levels activate, rather than inhibit, the HPA axis in rats. Since stress activates glucocorticoid production and increases FFA levels due to lipolysis, it is possible that FFA and the HPA axis constitute a previously unrecognized positive feedback loop.(ABSTRACT TRUNCATED AT 400 WORDS)

Adrenocorticotropic Hormone↗

Minireview: Neuro-immuno-endocrine modulation of the hypothalamic-pituitary-adrenal (HPA) axis by gp130 signaling molecules.

The neuroendocrine and immune systems communicate bidirectionally. The neuro-immune-endocrine interface is mediated by cytokines acting as auto/paracrine or endocrine factors regulating pituitary development, cell proliferation, hormone secretion, and feedback control of the hypothalamic-pituitary-adrenal (HPA) axis. At birth or during neonatal ontogenesis, cytokines produce permanent alterations of HPA axis function and the stress response. Overexpressing IL-6 or leukemia inhibitory factor leads to significant changes in pituitary development and functions. Pituitary corticotroph POMC gene expression is regulated by CRH as well as several gp130 cytokines acting as neuro-immuno-endocrine modulators. Conversely, HPA axis functions modulate susceptibility or resistance to inflammatory disease. Cytokines (including IL-1, TNF, and members of the gp130 cytokine family) participate as mediators of a complex HPA axis response to stress and inflammation. Prolonged exposure to proinflammatory cytokines increases levels of the dominant negative glucocorticoid receptor isoform. Nonresponsiveness of the HPA axis to glucocorticoid negative feedback control provides a defense from destructive effects of cytokine excess. At the same time, gp130 cytokines stimulate pituitary suppressor of cytokine signaling (SOCS)-3, which represses cytokine signaling and abrogates cytokine-induced corticotroph POMC gene transcription and ACTH secretion.

Animals↗

Altered responsiveness of the hypothalamus-pituitary-adrenal axis and the sympathetic adrenomedullary system to stress in patients with atopic dermatitis.

A growing number of animal data strongly suggest that a hyporeactive hypothalamus-pituitary adrenal (HPA) axis may be pathologically significant by increasing the susceptibility to chronic inflammation. Following this line of evidence, the specific goal of the present study was to investigate the HPA axis in patients with atopic dermatitis (AD), a chronic allergic inflammatory disease. In addition, the sympathetic adrenomedullary (SAM) system as a second potent immunoregulatory and anti-inflammatory stress-response system has been examined. AD patients (n = 36) and nonatopic control subjects (n = 37) were exposed to a standardized laboratory stressor consisting of a free speech and mental arithmetic task in front of an audience. Cortisol, ACTH, and catecholamine concentrations were assessed before and after the stressor. To investigate feedback sensitivity of the HPA axis, a low dose (0.5 mg) dexamethasone suppression test was also performed. AD patients showed significantly attenuated cortisol and ACTH responses to the stressor, whereas catecholamine levels were significantly elevated in atopic patients. No difference between the experimental groups was found in basal cortisol and ACTH concentrations, whereas basal catecholamine levels were significantly elevated. Analysis of cortisol levels after dexamethasone treatment suggested an intact feedback sensitivity in AD sufferers at the pituitary level. The present findings suggest that patients with AD demonstrate a blunted HPA axis responsiveness with a concurrent overreactivity of the SAM system to psychosocial stress. Considering the important immunoregulatory role of the HPA axis and the SAM system, especially under stressful conditions, an aberrant responsiveness of these neuroendocrine systems may increase the susceptibility to (allergic) inflammation and may be one psychobiological mechanism of stress-related aggravation of the disease.

Activity Cycles↗

The stimulatory effect of canrenoate, a mineralocorticoid antagonist, on the activity of the hypothalamus-pituitary-adrenal axis is abolished by alprazolam, a benzodiazepine, in humans.

Mineralocorticoid receptors (MR) in the hippocampus play a major role in the control of the hypothalamus-pituitary-adrenal (HPA) axis, mediating the proactive feedback of glucocorticoids in the maintenance of basal activity. Intracerebroventricular and intrahippocampal MR blockade stimulates HPA axis in animals; the systemic administration of mineralocorticoid antagonists enhances spontaneous and CRH-stimulated ACTH and cortisol secretion in humans. Benzodiazepines, namely alprazolam, activate central gamma-aminobutyric acid (GABA)ergic receptors, which are mainly distributed in the hippocampus. Alprazolam has a inhibitory effect on HPA axis either in basal conditions or after central nervous system-mediated stimuli. In humans, alprazolam strongly reduces the corticotroph responsiveness to removal of glucocorticoid feedback by metyrapone. We studied the effect of alprazolam (0.02 mg/kg, orally) on the effect of canrenoate (CAN), an MR antagonist (200 mg as an iv bolus, followed by 200 mg infused in 250 ml saline) or placebo on ACTH, cortisol, and dehydroepiandrosterone (DHEA) secretion in six normal young women (aged 25-32 yr; body mass index, 19-23 kg/m(2)). During placebo, ACTH, cortisol, and DHEA secretion showed a progressive decrease (baseline vs. nadir, mean +/- SEM, from 1830-2400 h, 2.6 +/- 0.3 vs. 1.4 +/- 0.3 pmol/liter, 133.2 +/- 16.4 vs. 46.9 +/- 5.2 nmol/liter, and 22.6 +/- 2.3 vs. 18.6 +/- 2.3 nmol/liter, respectively), although statistical significance was obtained for ACTH and cortisol only (P < 0.05). During CAN treatment, ACTH, cortisol, and DHEA secretion showed a progressive rise, which began at approximately 2100 h and peaked between 2300 and 2400 h (2.9 +/- 0.3 pmol/liter, 172.6 +/- 27.9 nmol/liter, and 45.3 +/- 10.7 nmol/liter, respectively; P < 0.05). Alprazolam abolished the CAN-induced increases in ACTH, cortisol, and DHEA levels (1.8 +/- 0.1 pmol/liter, 59.7 +/- 8.6 nmol/liter, and 19.8 +/- 6.7 nmol/liter; P < 0.05), inducing hormonal peaks overlapping with those recorded after placebo in the absence of any treatment. In conclusion, our study demonstrates that the inhibitory effect of GABAergic activation by alprazolam overrides the stimulatory effect of mineralocorticoid blockade by canrenoate on the HPA axis in humans. These findings emphasize the role of GABA in the control of the HPA axis in humans.

Adrenal Glands↗

No damaging effect of chemotherapy in addition to radiotherapy on the thyroid axis in young adult survivors of childhood cancer.

Late effects of treatment for childhood cancer on the thyroid axis are ascribed predominantly to radiotherapy. Whether chemotherapy has an additional detrimental effect is still unclear. Our aim was to evaluate this effect in young adult survivors of a broad spectrum of childhood cancers. The thyroid axis in 205 childhood cancer survivors was evaluated in relation to former use of chemotherapy and radiotherapy (cranial, cranio-spinal, cervical, mediastinal, or thoracic). The mean follow-up time was 17.5 yr. Damage to the thyroid axis was found in 55 patients (26.8%). Thirty-seven patients (18%) had thyroidal disease. Diagnoses varied from TSH elevation to papillary carcinoma. After multivariate analysis, high risk radiation field, irradiation dose, and the diagnosis of non-Hodgkin lymphoma/Hodgkin's disease were found to be significant risk factors for developing thyroid disease. Treatment with chemotherapy did not have an additional negative effect on the thyroid axis. For the development of central (pituitary or hypothalamic) thyroid dysfunction, patients with a brain tumor were at increased risk. Chemotherapy for childhood cancer does not contribute to the damage on the thyroid axis inflicted by radiotherapy during young adulthood.

Adolescent↗