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BACKGROUND: The mechanisms by which a derangement of glucose metabolism causes high blood pressure are not fully understood. OBJECTIVES: This study aimed to clarify the relation between salt sensitivity of blood pressure and insulin resistance, which are important subcharacteristics of hypertension and impaired glucose metabolism, respectively. Effects on the renin-angiotensin and sympathetic nervous systems were also studied. DESIGN: The state of glucose metabolism was assessed by a hyperinsulinemic euglycemic glucose clamp technique and a 75-g oral-glucose-tolerance test in 24 essential hypertensive patients who were lean and without diabetes or chronic kidney disease. The subjects were classified as salt-sensitive or salt-resistant on the basis of the difference (Delta mean blood pressure > or =5%) between 24-h ambulatory blood pressure monitoring results on the seventh day of low-salt (34 mmol/d) and high-salt (252 mmol/d) diets. Urine and blood samples were collected for analyses. RESULTS: There was a robust inverse relation between the glucose infusion rate (GIR) and the salt sensitivity index. The GIR correlated directly with the change in urinary sodium excretion and was inversely related to the change in hematocrit when the salt diet was changed from low to high, which is indicative of salt and fluid retention in salt-sensitive subjects. The GIR also showed an inverse correlation compared with the changes in urinary norepinephrine excretion, plasma renin activity, and plasma aldosterone concentration. CONCLUSIONS: Salt sensitivity of blood pressure is strongly associated with insulin resistance in lean, essential hypertensive patients. Hyperinsulinemia, sympathetic overactivation, and reduced suppression of the renin-angiotensin system may play a role in this relation. © 2010 American Society for Nutrition. [ABSTRACT FROM AUTHOR]

There are differences in the responsiveness to differential diagnostic tests for Cushing's disease (CD), corticotroph tumor size, and the somatostatin receptor (SSTR) 5 expression in corticotroph tumors between CD patients. The differences in SSTR5 expression are particularly significant for identifying therapeutic targets for CD. However, prospective predictors of SSTR5 expression remain unclear. Thus, our objective was to elucidate the relationships among these clinical characteristics of CD, including SSTR5 expression. In 27 hospitalized patients with CD at Osaka University Hospital, Osaka, Japan, associations between corticotroph tumor diameter, the response of ACTH and cortisol to differential diagnostic tests for CD (CRH, desmopressin [DDAVP], and high-dose dexamethasone suppression test [HDDST]), the ACTH/cortisol index, and the SSTR5 immunoreactive score were retrospectively investigated. The response to differential diagnostic tests, ACTH/cortisol index, tumor diameter, and SSTR5 expression were significantly related (vs. tumor diameter [CRH: r = -0.54; DDAVP: r = -0.54; HDDST r = -0.67; ACTH/cortisol index: r = 0.76; SSTR5: r = -0.61], vs. CRH [DDAVP: r = 0.63, HDDST: r = 0.72, ACTH/cortisol index: r = -0.45; SSTR5: r = 0.56], vs. DDAVP [HDDST: r = 0.66; ACTH/cortisol index: r = -0.46; SSTR5: r = 0.76], vs. HDDST [ACTH/cortisol index: r = -0.62; SSTR5: r = 0.77], ACTH/cortisol index vs. SSTR5: r = -0.67). The areas under the receiver operating characteristic curve for the prediction of high SSTR5 expression via the CRH test, DDAVP test, HDDST, ACTH/cortisol index, and tumor diameter were 0.79, 0.87, 0.80, 0.71, and 0.71, respectively. Tests for differential diagnosis of CD, the ACTH/cortisol index, and the corticotroph tumor diameter have the potential for identifying SSTR5 expression in corticotroph tumors. These parameters may reflect the biological characteristics of corticotroph tumors.

Objective Cortisol-producing adenoma (CPA) is a major subtype of functional adrenal tumors. CPAs are generally treated with adrenalectomy; however, it is difficult to predict the ideal duration of glucocorticoid replacement after resection. This study explored pre-operative factors predictive of glucocorticoid replacement therapy duration after CPA resection. Mehtods This multicenter retrospective observational study was conducted as part of the Advancing Care and Pathogenesis of Intractable Adrenal Diseases in Japan (ACPA-J) from January 2006 to December 2015. Patients This study was conducted at 10 referral centers and included 124 patients who received hydrocortisone replacement therapy after adrenalectomy for CPA. Results The median duration of replacement therapy was 12 (interquartile range, 5-24) months. In the single regression analysis, the sex (P=0.04), morning ACTH level (P=0.02), morning serum cortisol level (P=0.003), midnight serum cortisol level (P<0.001), serum cortisol level after a 1-mg dexamethasone suppression test (P<0.001), presence of lumbar compression fracture (P=0.015), and Cushingoid appearance (P<0.001) were all significantly associated with the replacement therapy duration. In multiple regression analyses, the midnight serum cortisol level and presence of lumbar compression fracture were significantly correlated with the replacement therapy duration after adjusting for other parameters. Conclusion Our results suggest that high midnight serum cortisol levels, which cause persistent suppression of the HPA axis, contribute to a delay in HPA axis recovery. Lumbar compression fracture is an important symptom that reflects the severity and persistence of cortisol secretion.

Unique polymer hydrogels with unusual cross-linking networks and self-healing properties have been recently reported. In this study, we fabricated hybrid hydrogels consisting of a chiral supramolecular one-dimensional assembly of glutamide-derived lipids bearing pyridinium head groups ( G -Py + ) cross-linked with termini-anionised hydrophilic polyethylene glycol polymers (S-PEG n -S). The cationic group-linked G -Py + forms nanotubular aggregates in water. G -Py + /S-PEG n -S aqueous mixtures formed hydrogels at certain concentrations and ambient temperatures. The terminal anionic sulfate groups play a key role in hydrogel formation, as evidenced by the absence of gelation in G -Py + /PEG n . The negative circular dichroism signal observed for pyridinium exhibited a blue shift upon the addition of S-PEG n -S but maintained its signal intensity even with excess S-PEG n -S, suggesting the chiral orientation of the nanofibrous G -Py + self-assembly preserved even complexation with S-PEG n -S in hydrogel. The hybrid hydrogel of sulfated polyethylene glycol with nanofibrous chiral supramolecular assembly exhibited self-healing property at a temperature below the gel-to-liquid crystalline phase transition ( T C ) of G -Py + aggregates, which was evidenced by the inversion fluid method and viscoelastic measurements., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Aldosterone secretion in primary aldosteronism (PA) is often regulated by adrenocorticotropic hormone (ACTH) in addition to its autonomous secretion. However, the clinical characteristics and risk of cardiovascular and cerebrovascular (CCV) events in PA patients with aldosterone responsiveness to ACTH stimulation remain unclear. This study aimed to investigate the prevalence of CCV events in PA patients with high aldosterone responsiveness to ACTH stimulation. A retrospective cross-sectional study was conducted as part of the Japan Primary Aldosteronism Study/Japan Rare Intractable Adrenal Disease project. PA patients with adrenal venous sampling (AVS) between January 2006 and March 2019 were enrolled. The ACTH-stimulated plasma aldosterone concentration (PAC) of the inferior vena cava during AVS was used to evaluate aldosterone responsiveness to ACTH. We analyzed the relationship between responsiveness and previous CCV events. Logistic regression analysis demonstrated that the ΔPAC (the difference between the PAC measurements before and after ACTH stimulation) significantly increased the odds of previous CCV events in PA patients after adjusting for classical CCV event risk factors, baseline PAC and duration of hypertension (relative PAC: odds ratio [OR], 2.896; 95% confidence interval [CI], 0.989-8.482; ΔPAC: OR, 2.344; 95% CI, 1.149-4.780; ACTH-stimulated PAC: OR, 2.098; 95% CI, 0.694-6.339). This study clearly demonstrated that aldosterone responsiveness to ACTH is closely related to previous CCV events. The responsiveness of the PAC to ACTH could be useful in predicting CCV event risk.Registration Number in UMIN-CTR is UMIN000032525.