Search results for "Adrenocorticotropic Hormone"
showing 10 items of 55 documents
Effects of 3,5-diiodo-L-thyronine on the liver of high fat diet fed rats
2016
Experimental studies have highlighted that the administration of 3,5-diiodo-L-thyronine (T2) to rats fed diets rich in lipids induces a decrease of cholesterol and triglycerides plasma levels and body weight (BW) without inducing liver steatosis. On the basis of these observations we carried out some experimental <em>in vivo</em> studies to assess the effects of multiple high doses of T2 on the pituitary thyroid axis of rats fed diet rich in lipids. Fifteen male Wistar rats were divided into three groups of five animals each. The first group (N group) received standard diet, the second group was fed with a high fat diet (HFD group), while the third group (HFDT2 group) was additi…
Involvement of interleukin-1 type 1 receptors in lipopolysaccharide-induced sickness responses
2017
Sickness responses to lipopolysaccharide (LPS) were examined in mice with deletion of the interleukin (IL)-1 type 1 receptor (IL-1R1). IL-1R1 knockout (1(0) mice displayed intact anorexia and HPA-axis activation to intraperitoneally injected LPS (anorexia: 10 or 120 mu g/kg; HPA-axis: 120 mu g/kg), but showed attenuated but not extinguished fever (120 g/kg). Brain PGE2 synthesis was attenuated, but Cox-2 induction remained intact. Neither the tumor necrosis factor-alpha (TNF alpha) inhibitor etanercept nor the IL -6 receptor antibody tocilizumab abolished the LPS induced fever in IL -1R1 KO mice. Deletion of IL -1R1 specifically in brain endothelial cells attenuated the LPS induced fever, b…
Pterostilbene Decreases the Antioxidant Defenses of Aggressive Cancer Cells In Vivo: A Physiological Glucocorticoids- and Nrf2-Dependent Mechanism
2016
Abstract Aims: Polyphenolic phytochemicals have anticancer properties. However, in mechanistic studies, lack of correlation with the bioavailable concentrations is a critical issue. Some reports had suggested that these molecules downregulate the stress response, which may affect growth and the antioxidant protection of malignant cells. Initially, we studied this potential underlying mechanism using different human melanomas (with genetic backgrounds correlating with most melanomas), growing in nude mice as xenografts, and pterostilbene (Pter, a natural dimethoxylated analog of resveratrol). Results: Intravenous administration of Pter decreased human melanoma growth in vivo. However, Pter, …
Perfusion MRI in normal and abnormal pituitary gland. A preliminary study.
1997
Perfusion MRI (magnetic resonance imaging) of the pituitary gland was performed in 20 healthy volunteers and 63 patients with various lesions involving the pituitary gland. All patients underwent sequential contrast-enhanced MRI using spoiled gradient recalled sequences with high temporal resolution (7 seconds). Four pituitary areas (pituitary stalk, posterior lobe, postero-superior, and antero-inferior adenohypophysis) were tested with a selected region of interest. Maximal contrast percentual variation was calculated. The timing of enhancement in normal patients matched perfectly with normal pituitary vascularization. Abnormal timing in pathological condition was investigated.
Acute hormonal responses to heavy resistance exercise in younger and older men
1998
The purpose of this investigation was to examine the acute responses of several hormones [total and free testosterone (TT and FT, respectively), adrenocorticotropic hormone (ACTH), cortisol (C), growth hormone (GH), and insulin (INS)] to a single bout of heavy resistance exercise (HRE). Eight younger [30-year (30y) group] and nine older [62-year (62y) group] men matched for general physical characteristics and activity levels performed four sets of ten repetitions maximum (RM) squats with 90 s rest between sets. Blood samples were obtained from each subject via an indwelling cannula with a saline lock pre-exercise, immediately post-exercise (IP), and 5, 15 and 30 min post-exercise. Levels o…
Indications of the occurrence of inflammatory reactions in the clinical improvement phase in multiple sclerosis patients.
2009
– In patients with multiple sclerosis (MS) the spontaneous burst activity (BA) of peripheral blood mononuclear cells was related to the clinical course of the disease. In five patients clinical improvement was found while the BA was significantly increased (more than 300% of the controls). During the appearance of new or deteriorating signs and in the period without clinical changes, the BA was not at all or not markedly increased. In two patients without clinical improvement the BA did not reach levels above 300% of the controls. Our findings suggest that inflammatory reactions represented by the BA occur in the phase of clinical improvement. Since burst-stimulating activity was found in t…
Pituitary-adrenal responses to corticotropin-releasing factor in late onset 21-hydroxylase deficiency
1990
Intravenous corticotropin-releasing factor (CRF) and adrenocorticotropin hormone (ACTH) were administered in patients with adult onset 21-hydroxylase deficiency to compare their diagnostic capability as well as to investigate hypothalamic-pituitary-adrenal function in this disorder. Responses of 17-hydroxyprogesterone, which were markedly elevated compared with controls, were identical with CRF and ACTH. However, intravenous ACTH resulted in higher androstenedione levels in comparison to CRF. Adrenocorticotropin hormone also resulted in decreased cortisol responses, confirming a defect in steroidogenesis, a finding that was not evident with CRF. Plasma ACTH responses to CRF were similar in …
Ovine corticotropin-releasing factor and dexamethasone responses in hyperandrogenic women
1990
Eighteen hyperandrogenic, hirsute women received ovine corticotropin-releasing factor (CRF; 1 microgram/kg) as well as a dexamethasone (DEX) suppression test. Nine of the 18 hirsute women exhibited increased DEX sensitivity. Plasma adrenocorticotropic hormone (ACTH) responses after ovine CRF were significantly lower in the DEX-sensitive subgroup, but serum androstenedione was higher. Baseline serum androgen levels could not predict DEX responses. A significant negative correlation existed between the suppression of androgens after DEX and the increase in ACTH after ovine CRF. The suppression of androgen correlated with the ratio of the increase in androgen to the increase in ACTH after ovin…
The endocrine pattern of late onset adrenal hyperplasia (21-hydroxylase deficiency)
1984
We describe 5 adult women with severe hirsutism due to late onset 21-hydroxylase deficiency. Diagnosis was performed on the finding of high serum 17-hydroxyprogesterone (17OHP) levels with a marked hyperresponse to an ACTH test. The endocrine study showed in most patients a gonadotropin behavior similar to that observed in classical polycystic ovary (PCO) syndrome. Prolactin levels were slightly increased in basal conditions and presented an exaggerated response to TRH stimulation.
Effect of serotonin uptake inhibition by zimelidine on hypothalamic-pituitary-adrenal activity
1983
Plasma ACTH levels after oral ingestion of 2 g metyrapone at 24.00 hours in six healthy subjects were higher after pretreatment with zimelidine (300 mg) in comparison to placebo. Since zimelidine is a relatively selective serotonin reuptake inhibitor its action on hypothalamic-pituitary-adrenal (HPA) activity suggests that serotonin is a potent stimulator of ACTH release. The ratio of cortisol to 11-deoxycortisol was taken as a measure of 11-hydroxylase activity, which indicates biological activity of secreted ACTH. These cortisol/11-deoxycortisol ratios were significantly increased after zimelidine treatment, when compared to placebo. Both the ACTH response and the cortisol/11-deoxycortiso…