MRI-based adrenal gland volume is associated with cardiovascular alterations in individuals without prior cardiovascular disease.

Aim of this study was to analyse the associations of cardiovascular health and adrenal gland volume as a rather new imaging biomarker of chronic hypothalamic-pituitary-adrenal (HPA) axis activation. The study population originates from the KORA population-based cross-sectional prospective cohort. 400 participants without known cardiovascular disease underwent a whole-body MRI. Manual segmentation of adrenal glands was performed on VIBE-Dixon gradient-echo sequence. MRI based evaluation of cardiac parameters was achieved semi-automatically. Cardiometabolic risk factors were obtained through standardized interviews and medical examination. Univariate and multivariate associations were derived. Bi-directional causal mediation analysis was performed. 351 participants were eligible for analysis (56 ± 9.1 years, male 58.7%). In multivariate analysis, significant associations were observed between adrenal gland volume and hypertension (outcome hypertension: Odds Ratio = 1.11, 95% CI [1.01, 1.21], p = 0.028), left ventricular remodelling index (LVRI) (outcome LVRI: ß = 0.01, 95% CI [0.00, 0.02], p = 0.011), and left ventricular (LV) wall thickness (outcome LV wall thickness: ß = 0.06, 95% CI [0.02, 0.09], p = 0.005). In bi-directional causal mediation analysis adrenal gland volume had a borderline significant mediating effect on the association between hypertension and LVRI (p = 0.052) as well as wall thickness (p = 0.054). MRI-based assessment of adrenal gland enlargement is associated with hypertension and LV remodelling. Adrenal gland volume may serve as an indirect cardiovascular imaging biomarker.

Suppression of adult cytogenesis in the rat brain leads to sex-differentiated disruption of the HPA axis activity.

OBJECTIVES: The action of stress hormones, mainly glucocorticoids, starts and coordinates the systemic response to stressful events. The HPA axis activity is predicated on information processing and modulation by upstream centres, such as the hippocampus where adult-born neurons (hABN) have been reported to be an important component in the processing and integration of new information. Still, it remains unclear whether and how hABN regulates HPA axis activity and CORT production, particularly when considering sex differences. MATERIALS AND METHODS: Using both sexes of a transgenic rat model of cytogenesis ablation (GFAP-Tk rat model), we examined the endocrinological and behavioural effects of disrupting the generation of new astrocytes and neurons within the hippocampal dentate gyrus (DG). RESULTS: Our results show that GFAP-Tk male rats present a heightened acute stress response. In contrast, GFAP-Tk female rats have increased corticosterone secretion at nadir, a heightened, yet delayed, response to an acute stress stimulus, accompanied by neuronal hypertrophy in the basal lateral amygdala and increased expression of the glucocorticoid receptors in the ventral DG. CONCLUSIONS: Our results reveal that hABN regulation of the HPA axis response is sex-differentiated.

Brain structural network alterations related to serum cortisol levels in drug-naïve, first-episode major depressive disorder patients: a source-based morphometric study.

Higher cortisol levels due to a hyperactive hypothalamic-pituitary-adrenal axis have been reported in patients with major depressive disorder (MDD). Increased cortisol levels change both the brain morphology and function in MDD patients. The multivariate source-based morphometry (SBM) technique has been applied to investigate neuroanatomical changes in some neuropsychiatric diseases, but not MDD. We aimed to examine the alterations in gray matter (GM) networks and their relationship with serum cortisol levels in first-episode, drug-naïve MDD patients using SBM. Forty-two patients with MDD and 39 controls were recruited via interviews. Morning serum cortisol levels were measured, and high-resolution T1-weighted imaging followed by SBM analysis was performed in all participants. The patients had significantly higher serum cortisol levels than the controls. We found two GM sources, which were significantly different between patients with MDD and controls (prefrontal network, p < .01; insula-temporal network, p < .01). Serum cortisol levels showed a statistically significant negative correlation with the loading coefficients of the prefrontal network (r = - 0.354, p = 0.02). In conclusion, increased serum cortisol levels were associated with reductions in the prefrontal network in the early stage of MDD, and SBM may be a useful approach for analyzing structural MRI data.

The influence of hypertensive environment on adipose tissue remodeling measured by fluorescence lifetime imaging in spontaneously hypertensive rats.

There is a lack of information correlating low adiposity with hypertension experienced by Spontaneous Hypertensive Rats (SHR) or overweight and normotension in Wistar-Kyoto (WKY). We aimed to investigate this lipodystrophy phenomenon by measuring fluorescence lifetime (FLIM), optical redox ratio (ORR), serum levels of hypothalamic-pituitary-adrenal (HPA) and/or hypothalamic-pituitary-thyroid (HPT) hormones axes between Wistar, WKY and SHR before and after establishment of hypertension. Under high blood pressure, we evaluated serum adipokines. Brown adipose tissue was characterized as lower ORR and shorter FLIM compared to white adipose tissue. HPT axis showed a crucial role in the SHR adipose tissue configuration by attenuating whitening. The increased adiposity in WKY may act as a preventive agent for hypertension, since SHR, with low adiposity, establishes the disease. The hypertensive environment can highlight key adipokines that may result in new therapeutic approaches to the treatment of adiposity dysfunctions and hypertension.

Chronic itch impairs mood and HPA axis function in mice: modulation by CRFR1 antagonist.

Chronic itch is clinically correlated with the development of mood disorders such as anxiety and depression. Nonetheless, whether this relevance exists in rodents is unknown, and evidence demonstrating chronic itch can affect mood is lacking. The aim of this study is to characterize the affective consequences of chronic itch, and explore potential mechanisms and interventional strategy. We subjected mice to chronic itch by repetitive cutaneous treatment with acetone and diethylether followed by water (AEW) that models "dry skin." After 3 to 4 weeks AEW treatment, the mice developed behavioral phenotypes of anxiety and depression assessed by a battery of behavioral paradigms, such as light-dark box and forced swim test. These behavioral symptoms of mood disturbance were independent of cutaneous barrier disruption, but correlated well with the degree of the irritating itch sensation. Although AEW mice showed normal circadian hypothalamic-pituitary-adrenal (HPA) axis activity, their neuroendocrine functionality was dampened, including impaired endocrine stress responsivity, altered neuroendocrine-immune interaction, and blunted corticosterone response to both dexamethasone and CRF. Parameters of HPA functionality at the level of mRNA transcripts are altered in stress-related brain regions of AEW mice, implying an overdrive of central CRF system. Remarkably, chronic treatment of AEW mice with antalarmin, a CRFR1 antagonist, ameliorated both their mood impairment and stress axis dysfunction. This is the first evidence revealing mood impairment, HPA axis dysfunction, and potential therapeutic efficacy by CRFR1 antagonist in mice with chronic itch, thus providing a preclinical model to investigate the affective consequence of chronic itch and the underlying mechanisms.

MANAGEMENT OF ENDOCRINE DISEASE: Can we cure Cushing's disease? A personal view.

One of today's challenges in endocrinology is the treatment of Cushing's disease: Although pituitary surgery has the potential to 'cure' the patient and restore a completely normal pituitary adrenal axis, there are immediate failures and late recurrences that will ultimately require alternate therapeutic approaches. Their high number is in direct correlation with their serious limitations and they all appear to be 'default options'. This 'personal view' tries to shed some light on the inescapable difficulties of the current treatments of Cushing's disease and to provide some optimistic view for the future where the pituitary adenoma should be the 'reasonable obsession' of a successful therapeutist.

Pituitary gland shrinkage in bipolar disorder: The role of gender.

BACKGROUND: Hyperactivity of the Hypothalamic-Pituitary-Adrenal Axis (HPAA) has been consistently reported in mood disorders. However, only few studies investigated the Pituitary gland (PG) in Bipolar Disorder (BD) and the results are so far contrasting. Therefore, the aim of this study is to explore the integrity of the PG as well as the role of gender and the impact of clinical measurements on this structure in a sample of BD patients compared to healthy controls (HC). METHODS: 34 BD patients and 41 HC underwent a 1.5 T MRI scan. PG volumes were manually traced for all subjects. Psychiatric symptoms were assessed by means of the Brief Psychiatry Rating Scale, the Hamilton Depression Rating Scale and the Bech Rafaelsen Mania Rating Scale. RESULTS: We found decreased PG volumes in BD patients compared to HC (F = 24.9, p < 0.001). Interestingly, after dividing the sample by gender, a significant PG volume decrease was detected only in female BD patients compared to female HC (F = 9.1, p < 0.001), but not in male BD compared to male HC (F = -0.12, p = 0.074). No significant correlations were observed between PG volumes and clinical variables. CONCLUSIONS: Our findings suggest that BD patients have decreased PG volumes, probably due to the long-term hyperactivity of the HPAA and to the consequent strengthening of the negative feedback control towards the PG volume itself. This alteration was particularly evident in females, suggesting a role of gender in affecting PG volumes in BD. Finally, the absence of significant correlations between PG volumes and clinical variables further supports that PG disruption is a trait feature of BD, being independent of symptoms severity and duration of treatment.

Coupling corticotropin-releasing-hormone and angiotensin converting enzyme 2 dampens stress responsiveness in male mice.

This study used mice to evaluate whether coupling expression of corticotropin-releasing hormone (CRH) and angiotensin converting enzyme 2 (ACE2) creates central interactions that blunt endocrine and behavioral responses to psychogenic stress. Central administration of diminazene aceturate, an ACE2 activator, had no effect on restraint-induced activation of the hypothalamic-pituitary-adrenal (HPA) axis; however, mice that ubiquitously overexpress ACE2 had reduced plasma corticosterone (CORT) and pituitary expression of POMC mRNA. The Cre-LoxP system was used to restrict ACE2 overexpression to CRH synthesizing cells and probe whether HPA axis suppression was the result of central ACE2 and CRH interactions. Within the paraventricular nucleus of the hypothalamus (PVN), mice with ACE2 overexpression directed to CRH had a ≈2.5 fold increase in ACE2 mRNA, which co-localized with CRH mRNA. Relative to controls, mice overexpressing ACE2 in CRH cells had a decreased CORT response to restraint as well as decreased CRH mRNA in the PVN and CEA and POMC mRNA in the pituitary. Administration of ACTH similarly increased plasma CORT, indicating that the blunted HPA axis activation that accompanies ACE2 overexpression in CRH cells is centrally mediated. Anxiety-like behavior was assessed to determine whether the decreased HPA axis activation was predictive of anxiolysis. Mice with ACE2 overexpression directed to CRH cells displayed decreased anxiety-like behavior in the elevated plus maze and open field when compared to that of controls. Collectively, these results suggest that exogenous ACE2 suppresses CRH synthesis, which alters the central processing of psychogenic stress, thereby blunting HPA axis activation and attenuating anxiety-like behavior.

HPA Axis Genes, and Their Interaction with Childhood Maltreatment, are Related to Cortisol Levels and Stress-Related Phenotypes.

Stress responses are controlled by the hypothalamus pituitary adrenal (HPA)-axis and maladaptive stress responses are associated with the onset and maintenance of stress-related disorders such as major depressive disorder (MDD). Genes that play a role in the HPA-axis regulation may likely contribute to the relation between relevant neurobiological substrates and stress-related disorders. Therefore, we performed gene-wide analyses for 30 a priori literature-based genes involved in HPA-axis regulation in 2014 subjects (34% male; mean age: 42.5) to study the relations with lifetime MDD diagnosis, cortisol awakening response, and dexamethasone suppression test (DST) levels (subsample N=1472) and hippocampal and amygdala volume (3T MR images; subsample N=225). Additionally, gene by childhood maltreatment (CM) interactions were investigated. Gene-wide significant results were found for dexamethasone suppression (CYP11A1, CYP17A1, POU1F1, AKR1D1), hippocampal volume (CYP17A1, CYP11A1, HSD3B2, PROP1, AVPRA1, SRD5A1), amygdala volume (POMC, CRH, HSD3B2), and lifetime MDD diagnosis (FKBP5 and CRH), all permutation p-values<0.05. Interactions with CM were found for several genes; the strongest interactions were found for NR3C2, where the minor allele of SNP rs17581262 was related to smaller hippocampal volume, smaller amygdala volume, higher DST levels, and higher odds of MDD diagnosis only in participants with CM. As hypothesized, several HPA-axis genes are associated with stress-related endophenotypes including cortisol response and reduced brain volumes. Furthermore, we found a pleiotropic interaction between CM and the mineralocorticoid receptor gene, suggesting that this gene plays an important moderating role in stress and stress-related disorders.

The Utility of Routine Ultrasound in the Diagnosis and Management of Adolescents with Abnormal Uterine Bleeding.

STUDY OBJECTIVE: Despite the fact that most cases of abnormal uterine bleeding (AUB) in adolescence are due to an immature hypothalamic-pituitary-ovarian (HPO) axis, the current approach to investigating adolescents who present with AUB often includes pelvic ultrasound to exclude rare structural causes. The aim of this study was to determine whether an ultrasound ordered for the investigation of AUB in adolescents detects any significant anatomic pathology or alters diagnosis and management. DESIGN, SETTING, PARTICIPANTS, AND INTERVENTIONS: A retrospective chart review of 230 patients younger than 18 years of age who presented with AUB to the gynecology clinic at the Hospital for Sick Children in Toronto, Canada between January 2010 and December 2012 was completed. MAIN OUTCOME MEASURES: Findings on pelvic ultrasound and any further imaging as well as management choices for these patients were examined. RESULTS: Of all patients, 67.8% (156/230) had ultrasound done as part of their AUB workup. The most common diagnosis for the patients who received ultrasound examinations and the patients who did not was AUB due to an immature HPO axis. Of the patients who received an ultrasound examination, 72.4% (113/156) had normal findings; incidental findings were identified in 17.9% (28/156) and polycystic ovary syndrome morphology in 6.4% (10/156). Structural causes of AUB were found in only 2 (1.3%) of the adolescents imaged. No patient had a change in her AUB management plan because of ultrasound findings. CONCLUSION: Our results strongly suggest that pelvic ultrasound examination is not required in the initial investigation of AUB in the adolescent population because it did not alter treatment in any of our patients.

Circadian and homeostatic modulation of functional connectivity and regional cerebral blood flow in humans under normal entrained conditions.

Diurnal rhythms have been observed in human behaviors as diverse as sleep, olfaction, and learning. Despite its potential impact, time of day is rarely considered when brain responses are studied by neuroimaging techniques. To address this issue, we explicitly examined the effects of circadian and homeostatic regulation on functional connectivity (FC) and regional cerebral blood flow (rCBF) in healthy human volunteers, using whole-brain resting-state functional magnetic resonance imaging (rs-fMRI) and arterial spin labeling (ASL). In common with many circadian studies, we collected salivary cortisol to represent the normal circadian activity and functioning of the hypothalamic-pituitary-adrenal (HPA) axis. Intriguingly, the changes in FC and rCBF we observed indicated fundamental decreases in the functional integration of the default mode network (DMN) moving from morning to afternoon. Within the anterior cingulate cortex (ACC), our results indicate that morning cortisol levels are negatively correlated with rCBF. We hypothesize that the homeostatic mechanisms of the HPA axis has a role in modulating the functional integrity of the DMN (specifically, the ACC), and for the purposes of using fMRI as a tool to measure changes in disease processes or in response to treatment, we demonstrate that time of the day is important when interpreting resting-state data.

[Effects of alpha lipoic acid on hypothalamus-pituitary-adrenal axis in rats].

OBJECTIVE: To study the functional and ultramicrostructural effects of alpha lipoic acid on hypothalamus-pituitary-adrenal (HPA) axis in normal and diabetic rats. METHODS: Using radioimmunoassay we observed the effects of three doses (1, 20, and 100 mg/kg) of alpha lipoic acid injected intraperitoneally for 3 weeks on the plasma levels of CRH, ACTH and COR in normal and diabetic rats. The ultramicrostructural changes of the hypophysis and pituitary gland after alpha lipoic acid treatment were observed under transmission electron microscope. RESULTS: Compared with the control group, CRH level in lipoicin-treated normal and diabetic rats was significantly reduced (P<0.05). ACTH level of the 3 lipoicin doses groups of normal rats decreased, and a significant reduction occurred in medium-dose lipoicin group of diabetic rats (P<0.05). COR level showed the same changes as CRH level in normal rats, but decreased significantly in high- and medium-dose lipoicin groups of diabetic rats. Lipoicin treatment produced no apparent effect on the ultramicrostructures of the hypophysis and pituitary gland cells, which were the targets of diabetic lesions with low metabolism functions. Lipoicin treatment obviously enhanced the hypophysis and pituitary gland cell metabolism function to resist diabetic oxidative stress. CONCLUSION: Lipoicin can inhibit the HPA axis directly or indirectly in normal and diabetic rats.

Subgenual prefrontal cortex activity predicts individual differences in hypothalamic-pituitary-adrenal activity across different contexts.

BACKGROUND: Hypothalamic-pituitary-adrenal (HPA) system activation is adaptive in response to stress, and HPA dysregulation occurs in stress-related psychopathology. It is important to understand the mechanisms that modulate HPA output, yet few studies have addressed the neural circuitry associated with HPA regulation in primates and humans. Using high-resolution F-18-fluorodeoxyglucose positron emission tomography (FDG-PET) in rhesus monkeys, we assessed the relation between individual differences in brain activity and HPA function across multiple contexts that varied in stressfulness. METHODS: Using a logical AND conjunctions analysis, we assessed cortisol and brain metabolic activity with FDG-PET in 35 adolescent rhesus monkeys exposed to two threat and two home-cage conditions. To test the robustness of our findings, we used similar methods in an archival data set. In this data set, brain metabolic activity and cortisol were assessed in 17 adolescent male rhesus monkeys that were exposed to three stress-related contexts. RESULTS: Results from the two studies revealed that subgenual prefrontal cortex (PFC) metabolism (Brodmann's area 25/24) consistently predicted individual differences in plasma cortisol concentrations regardless of the context in which brain activity and cortisol were assessed. CONCLUSIONS: These findings suggest that activation in subgenual PFC may be related to HPA output across a variety of contexts (including familiar settings and novel or threatening situations). Individuals prone to elevated subgenual PFC activity across multiple contexts may be individuals who consistently show heightened cortisol and may be at risk for stress-related HPA dysregulation.

Medial prefrontal cortex and right insula activity predict plasma ACTH response to trauma recall.

Neural substrates underlying psychological activation of the limbic-hypothalamic-pituitary-adrenal (LHPA) axis are not well understood in humans. Trauma recall (using autobiographical script-driven imagery) may provide a model to study neural circuitry involved in LHPA axis activation to personally threatening psychological stimuli. This study sought to identify brain activation patterns that differentiated combat veterans who mounted an LHPA response to trauma recall from those who did not. Twenty-five Vietnam combat veterans (14 with current PTSD, 11 with no PTSD history) experienced autobiographic script-driven imagery in an [(15)O] H(2)O positron emission tomography (PET) paradigm with recurrent blood sampling. Trauma recall elicited acute ACTH responses in some but not all veterans, regardless of the PTSD status and independent of emotional responses. ACTH responders (mean ACTH increase of 24+/-7 pg/ml, n=13) were compared to non-responders (mean decrease of -0.6+/-0.6 pg/ml, n=12) in regional cerebral blood flow (rCBF). Both groups activated right insula (BA13) in response to trauma recall. However, ACTH responders deactivated rostral mPFC (BA10)/rostral ACC (BA32), whereas non-responders activated this same mPFC region, and deactivated amygdala, hippocampus, and temporal pole. In group contrasts comparing ACTH responders to non-responders, the responders had significantly higher rCBF in right insula and right temporal pole, whereas non-responders had higher rCBF in rostral mPFC and dorsal ACC. These results support the hypotheses that right insula is involved in psychological activation of the LHPA axis and that rostral mPFC may negatively modulate LHPA axis responses.

Paralimbic and medial prefrontal cortical involvement in neuroendocrine responses to traumatic stimuli.

OBJECTIVE: Hypothalamic-pituitary-adrenal axis activity and cortisol release are consequences of central stress system activation, but they may also influence cognitive and emotional processes within the brain. Despite the importance of central stress response systems, little is known about the specific brain circuits through which psychosocial stimuli activate the hypothalamic-pituitary-adrenal axis and through which cortisol feedback modulates central processing. The authors used [(15)O]H(2)O positron emission tomography (PET) on subjects with posttraumatic stress disorder (PTSD) to study these circuits. METHOD: Participants were combat-PTSD patients, combat-exposed healthy comparison subjects, and noncombat-exposed healthy comparison subjects. Participants were scanned using [(15)O]H(2)O PET while they experienced a series of emotional-induction conditions, which included aversive pictures and autobiographic narratives. Blood samples were obtained 2 minutes before and 5 minutes after each activation scan in order to measure the subjects' plasma adrenocorticotropic hormone and cortisol levels. RESULTS: In voxel-wise analyses, the authors found that adrenocorticotropic hormone responses were covaried with regional cerebral blood flow (rCBF) in the dorsal medial prefrontal cortex, rostral anterior cingulate cortex, and right insula, with some differences between PTSD patients and comparison subjects. Prestimulus cortisol levels covaried with rCBF responses in the rostral anterior cingulate cortex. In combat-PTSD patients only, prestimulus cortisol levels covaried with rCBF in the subgenual anterior cingulate cortex. CONCLUSIONS: These findings provide evidence of cortical involvement in hypothalamic-pituitary-adrenal responses to psychological stimuli, specifically implicating the insula, dorsal medial prefrontal cortex, and rostral anterior cingulate cortex. These findings also show, for the first time, that cortisol may modulate activity in specific brain areas such as the rostral and subgenual anterior cingulate cortices. Differential patterns of covariation between combat veterans with and without PTSD potentially implicate the dorsal medial prefrontal cortex and subgenual anterior cingulate cortex as areas of dysregulation in PTSD.

Reversible MRI changes of hypothalamus in a multiple sclerosis patient with homeostatic disturbances.

Multiple sclerosis (MS) patients occasionally present with homeostatic disturbances suggestive of hypothalamic dysfunction; however, the hypothalamus often appears normal on imaging, apart from confirmation in a few necropsy studies. In this article we describe a Chinese woman with atypical clinical presentation. She presented with relapsing symptoms and signs consistent with hypothalamic dysfunction including hyperprolactinema, syndrome of inappropriate secretion of anti-diuretic hormone (SIADH), hypersomnolence and temperature dysregulation. Serial MRI depicted the atypical reversible changes in the hypothalamus, correlating with the observed homeostatic abnormalities.

Autonomy of cortisol secretion in clinically silent adrenal incidentaloma.

Recent progress in non-invasive imaging techniques have resulted in an increasing frequency of adrenal incidentaloma discovery. In addition, even clinically silent adrenal tumor has been suggested to possess a subtle production of adrenal hormones. The aim of the study was to ascertain the autonomy of cortisol production in clinically silent adrenocortical incidentaloma. We investigated the hypothalamic-pituitary-adrenal axis in 38 patients with adrenal incidentaloma. Basal plasma cortisol level was reproducibly within normal range in all the patients with adrenal incidentaloma, but was also normal in half of the Cushing's syndrome cases studied. Eighteen of 38 patients showed plasma cortisol above 3 microg/dl after 1 mg dexamethasone (Dex) and above 1 microg/dl after 8 mg Dex, respectively, and were defined as preclinical Cushing's syndrome. These patients were subjected to further evaluation of the autonomy of cortisol production. The incidence of positive findings indicating autonomy of cortisol secretion was as follows: suppressed basal plasma ACTH level in 44%, loss of normal diurnal rhythm in 79%, lack of ACTH response to CRF in 35%, decreased plasma DHEA-S level in 28%, significant laterality of 131I-adosterol uptake in 75%, atrophy of the contralateral side of the adrenal on CT scan in 6%, and histological atrophy of the adjacent adrenal cortex in 56%, respectively. The endocrine feature relevant to the hypothalamic-pituitary-adrenal axis varied from patient to patient, ranging from the non-functioning adrenal adenoma to Cushing's syndrome. In addition, the results of each test did not coincide with others in each patient. These results clearly demonstrated that the incidence of autonomy of cortisol production in the clinically silent adrenal incidentaloma is not infrequent, showing significant diversity. Systemic evaluation of the hypothalamic-pituitary-adrenal axis before adrenal surgery is warranted for an appropriate glucocorticoid replacement after adrenal surgery.

Hippocampal perfusion and pituitary-adrenal axis in Alzheimer's disease.

The hippocampus is involved in Alzheimer's disease (AD) and regulates the hypothalamus-pituitary-adrenal axis (HPAA). Enhanced cortisol secretion has been reported in AD. Increased cortisol levels affect hippocampal neuron survival and potentiate beta-amyloid toxicity. Conversely, dehydroepiandrosterone (DHEA) and its sulfate (DHEAS) are believed to antagonize noxious glucocorticoid effects and exert a neuroprotective activity. The present study was aimed at investigating possible correlations between hippocampus perfusion - evaluated by SPECT - and HPAA function in AD. Fourteen patients with AD and 12 healthy age-matched controls were studied by (99m)Tc-HMPAO high-resolution brain SPECT. Plasma adrenocorticotropin, cortisol, and DHEAS levels were determined at 2.00, 8.00, 14.00, 20.00 h in all subjects and their mean values were computed. Cortisol/DHEAS ratios (C/Dr) were also calculated. Bilateral impairment of SPECT hippocampal perfusion was observed in AD patients as compared to controls. Mean cortisol levels were significantly increased and DHEAS titers were lowered in patients with AD, as compared with controls. C/Dr was also significantly higher in patients. Using a stepwise procedure for dependent SPECT variables, the variance of hippocampal perfusional data was accounted for by mean basal DHEAS levels. Moreover, hippocampal SPECT data correlated directly with mean DHEAS levels, and inversely with C/Dr. These data show a relationship between hippocampal perfusion and HPAA function in AD. Decreased DHEAS, rather than enhanced cortisol levels, appears to be correlated with changes of hippocampal perfusion in dementia.

Psychoneuroendocrinology and brain imaging in depression.

In the past three decades, psychoneuroendocrinologic investigations have generated a great volume of information, particularly in the field of affective disorders, which has formed the basis for designing studies with newer tools such as anatomic and functional imaging. In this article, the authors focus on endocrine imaging in psychiatry and attempt to relate morphometric findings to physiologic neuroendocrine dysfunction in depression.

Changes of sympatho-adrenal and hypothalamo-pituitary-adrenocortical system in patients with head injury.

To determine the role of the sympatho-adrenal (SAS) and hypothalamo-pituitary-adrenocortical system (HPAS) after head injury, the relationship between venous blood epinephrine (E), norepinephrine (NE), adrenocorticotropic hormone (ACTH), cortisol levels, and clinical condition was examined in 55 patients. These observations suggest that head injury causes mainly activation of the above-mentioned systems depending on the severity of trauma. An inverse correlation between the levels of E, NE and Glasgow Coma Scale score, indicating the severity of head injury was revealed. ACTH and cortisol were similarly related to the clinical condition, although the observed correlation was less expressed. The changes in hormonal levels were present during the whole research period (1 week), although a certain shift to normalization was observed. However, catecholamines and ACTH levels in plasma were relatively low in severely head-injured patients whose CT scans revealed serious alterations in the mesencephalic-diencephalic area. At the same time their cortisol levels obtained maximal values and their chance to survive was diminutive. The results of this study indicate that investigation of hormones of SAS and HPAS might be useful as an additional method in the complex of ordinary examinations in establishing early prognosis in patients with brain injury.