| 1. |
- Kawai, Mayumi, et al.
(author)
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C-type natriuretic peptide as a possible local modulator of aldosterone secretion in bovine adrenal zona glomerulosa
- 1996
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In: Endocrinology. - : Oxford University Press. - 0013-7227 .- 1945-7170. ; 137:1, s. 42-46
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Journal article (peer-reviewed)abstract
- Although atrial and brain natriuretic peptides are well known to be involved in the regulation of cardiovascular and endocrine functions as circulating hormones, the roles of the C-type natriuretic peptide (CNP) remain unknown. We examined the effects of CNP on the secretion of aldosterone and cyclic nucleotides from bovine adrenal zona glomerulosa cells in culture. CNP produced a dose-dependent increase in the basal secretion of cGMP, with an EC50 of 3.8 x 10(-10)M. CNP significantly inhibited the ACTH-induced increase in aldosterone and cAMP in a dose-related manner, with an IC50 of 3.6 x 10(-10)M. Although ACTH itself did not increase cGMP secretion, the addition of CNP elicited a significant increase in cGMP secretion. The effects of CNP on the basal secretion of cGMP and the ACTH-induced secretion of aldosterone were significantly reversed by a nonpeptide natriuretic peptide receptor antagonist, HS-142-1. CNP immunoreactivity was localized in the zona glomerulosa by immunohistochemical staining. In addition, expression of CNP messenger RNA and natriuretic peptide B receptor messenger RNA was demonstrated by RT-PCR in the zona glomerulosa tissue and cells in culture. These findings suggest that CNP is a local factor regulating ACTH-induced aldosterone secretion through a guanylyl cyclase-cGMP pathway.
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| 2. |
- Yoshimoto, Takanobu, et al.
(author)
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Angiotensin Converting Enzyme Inhibitor Normalizes Vascular Natriuretic Peptide Type A Receptor Gene Expression via Bradykinin-Dependent Mechanism in Hypertensive Rats
- 1996
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In: Biochemical and Biophysical Research Communications - BBRC. - : Elsevier. - 0006-291X .- 1090-2104. ; 218:1, s. 50-53
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Journal article (peer-reviewed)abstract
- We previously demonstrated that angiotensin converting enzyme (ACE) inhibitor normalizes the up-regulated gene expression of vascular natriuretic peptide type A (NP-A) receptor in hypertensive rats. To elucidate the mechanism, we examined the effect of angiotensin II receptor (AT1) antagonist (TCV-116) and bradykinin receptor (B2) antagonist (Hoe 140) on the NP-A receptor mRNA level in the aorta of genetically hypertensive rats (SHR-SP/Izm) using ribonuclease protection assay. The effect of ACE inhibitor on the NP-A receptor mRNA level was completely abolished by a concomitant administration of Hoe 140, while TCV-116 did not show any significant effect on the NP-A receptor mRNA level. These results suggest that bradykinin plays an important role in the regulation of the vascular NP-A receptor gene expression.
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| 3. |
- Yoshimoto, Takanoubu, et al.
(author)
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Angiotensin II-dependent down-regulation of vascular natriuretic peptide type C receptor gene expression in hypertensive rats
- 1996
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In: Endocrinology. - : Oxford University Press. - 0013-7227 .- 1945-7170. ; 137:3, s. 1102-1107
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Journal article (peer-reviewed)abstract
- Biological actions of natriuretic peptide (NP) are determined by the condition of the receptor as well as that of the hormone. Although we previously demonstrated in hypertensive rats the up-regulation of NP-A receptor that mediates various biological actions of NPs, the pathophysiologic significance of NP-C receptor, another subtype thought to be related to clearance of NPs and possibly to biological actions, remains unknown. In the present study, we determined NP-C receptor messenger RNA (mRNA) level in the aortic tissue of stroke-prone spontaneously hypertensive rats (SHR-SP/Izm) and in cultured aortic smooth muscle cells by ribonuclease protection assay. The aortic NP-C receptor mRNA level in SHR-SP/Izm was significantly lower than that in the control WKY/Izm. Oral administration of an angiotensin (Ang) II receptor (AT1) antagonist, TCV-116, but not a calcium channel blocker, manidipine, reversed the down-regulated NP-C receptor mRNA in SHR-SP/Izm to the level in WKY/Izm, whereas the latter was more potent in decreasing the blood pressure. In cultured aortic smooth muscle cells, the NP-C receptor was the predominant subtype. Ang II decreased the NP-C receptor mRNA level in a dose-dependent manner, but this effect was reversed by an AT1 antagonist, CV-11974. Neither the NP-A nor NP-B receptor mRNA level was altered by Ang II. These findings indicate that vascular NP-C receptor is down- regulated via Ang-II-mediated mechanism in SHR-SP/Izm. The phenomenon, together with the up-regulation of the NP-A receptor, may play an important role in counteracting hypertension by enhancing the action of NPs.
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| 4. |
- Yoshimoto, Takanobu, et al.
(author)
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Differential Gene Expression of Vascular Natriuretic Peptide Receptor Subtype in Artery and Vein
- 1995
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In: Biochemical and Biophysical Research Communications - BBRC. - : Elsevier. - 0006-291X .- 1090-2104. ; 216:2, s. 535-539
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Journal article (peer-reviewed)abstract
- Although the vasorelaxation by natriuretic peptide (NP) is much less potent in the vein than in the artery, mechanism underlying the phenomenon remains unknown. Since NP receptor consists of three subtypes with different functions, we determined the mRNA level of each NP receptor subtype in the artery and vein by ribonuclease protection assay. In the aorta, NP-A receptor related to the biological action of NP was the predominant form. By contrast, NP-C receptor related mainly to the clearance of NP was the predominant form in the inferior vena cava: NP-C mRNA level was about two fold higher than in the aorta, while both NP-A and NP-B receptor mRNA levels were about half of that in the aorta. These results provide the molecular basis for the different biological response to NP in the artery and vein. Differential gene expression of NP receptor subtype could be an important determinant of the biological actions of NP.
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| 5. |
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| 6. |
- Crona, Joakim, et al.
(author)
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ENSAT registry-based randomized clinical trials for adrenocortical carcinoma
- 2021
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In: European Journal of Endocrinology. - : Bioscientifica. - 0804-4643 .- 1479-683X. ; 184:2, s. R51-R59
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Research review (peer-reviewed)abstract
- Adrenocortical carcinoma (ACC) is an orphan disease lacking effective systemic treatment options. The low incidence of the disease and high cost of clinical trials are major obstacles in the search for improved treatment strategies. As a novel approach, registry-based clinical trials have been introduced in clinical research, so allowing for significant cost reduction, but without compromising scientific benefit. Herein, we describe how the European Network for the Study of Adrenal Tumours (ENSAT) could transform its current registry into one fit for a clinical trial infrastructure. The rationale to perform randomized registry-based trials in ACC is outlined including an analysis of relevant limitations and challenges. We summarize a survey on this concept among ENSAT members who expressed a strong interest in the concept and rated its scientific potential as high. Legal aspects, including ethical approval of registry-based randomization were identified as potential obstacles. Finally, we describe three potential randomized registry-based clinical trials in an adjuvant setting and for advanced disease with a high potential to be executed within the framework of an advanced ENSAT registry. Thus we, therefore, provide the basis for future registry-based trials for ACC patients. This could ultimately provide proof-of-principle of how to perform more effective randomized trials for an orphan disease.
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| 7. |
- Kobayashi, Hiroki, et al.
(author)
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Assessing Lateralization Index of Adrenal Venous Sampling for Surgical Indication in Primary Aldosteronism
- 2024
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In: JOURNAL OF CLINICAL ENDOCRINOLOGY & METABOLISM. - 0021-972X .- 1945-7197.
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Journal article (peer-reviewed)abstract
- Context Clinical practice guidelines recommend the lateralization index (LI) as the standard for determining surgical eligibility in primary aldosteronism (PA).Objective Our goal was to identify the optimal LI cutoffs in adrenal venous sampling (AVS) for diagnosing PA that is amenable to surgical cure.Methods We conducted a retrospective international cohort study across 16 institutions in 11 countries, including 1550 patients with PA who underwent AVS, with and/or without adrenocorticotropin (ACTH) stimulation. The establishment of optimal cutoffs was informed by a survey of 82 patients with PA in Japan, aimed at determining the LI cutoff aligned with patient expectations for a surgical cure rate.Results The survey revealed that a median cure rate expectation of 80% would motivate patients with PA towards undergoing adrenalectomy. The optimal LI cutoffs achieving an adjusted positive predictive value (PPV) of 80% were identified as 3.8 for unstimulated AVS and 3.4 for ACTH-stimulated AVS. Furthermore, a contralateral ratio of less than 0.4 and the detection of an adrenal nodule on computed tomography imaging were identified as independent predictors of surgically curable PA. Incorporating these factors with the optimal LI cutoffs, the adjusted PPV increased to 96.6% for unstimulated AVS and 89.6% for ACTH-stimulated AVS. No clear differences in predictive ability between unstimulated and ACTH-stimulated LI were found.Conclusion The present study clarified the optimal LI cutoffs for without and with ACTH stimulation. The presence of contralateral suppression and adrenal nodule on CT imaging seems to provide additional available information besides LI for surgical indication.
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| 8. |
- Naruse, Mitsuhide, et al.
(author)
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International multicenter survey on screening and confirmatory testing in primary aldosteronism.
- 2023
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In: European journal of endocrinology. - : Oxford University Press (OUP). - 1479-683X .- 0804-4643. ; 188:1
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Journal article (peer-reviewed)abstract
- Primary aldosteronism (PA) is one of the most frequent causes of secondary hypertension. Although clinical practice guidelines recommend a diagnostic process, details of the steps remain incompletely standardized.In the present SCOT-PA survey, we have investigated the diversity of approaches utilized for each diagnostic step in different expert centers through a survey using Google questionnaires. A total of 33 centers from 3 continents participated.We demonstrated a prominent diversity in the conditions of blood sampling, assay methods for aldosterone and renin, and the methods and diagnostic cutoff for screening and confirmatory tests. The most standard measures were modification of antihypertensive medication and sitting posture for blood sampling, measurement of plasma aldosterone concentration (PAC) and active renin concentration by chemiluminescence enzyme immunoassay, a combination of aldosterone-to-renin ratio with PAC as an index for screening, and saline infusion test in a seated position for confirmatory testing. The cutoff values for screening and confirmatory testing showed significant variation among centers.Diversity of the diagnostic steps may lead to an inconsistent diagnosis of PA among centers and limit comparison of evidence for PA between different centers. We expect the impact of this diversity to be most prominent in patients with mild PA. The survey raises 2 issues: the need for standardization of the diagnostic process and revisiting the concept of mild PA. Further standardization of the diagnostic process/criteria will improve the quality of evidence and management of patients with PA.
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| 9. |
- Taïeb, David, et al.
(author)
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Management of phaeochromocytoma and paraganglioma in patients with germline SDHB pathogenic variants : an international expert Consensus statement
- 2024
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In: Nature Reviews Endocrinology. - : Springer Nature. - 1759-5029 .- 1759-5037. ; 20:3, s. 168-184
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Research review (peer-reviewed)abstract
- Adult and paediatric patients with pathogenic variants in the gene encoding succinate dehydrogenase (SDH) subunit B (SDHB) often have locally aggressive, recurrent or metastatic phaeochromocytomas and paragangliomas (PPGLs). Furthermore, SDHB PPGLs have the highest rates of disease-specific morbidity and mortality compared with other hereditary PPGLs. PPGLs with SDHB pathogenic variants are often less differentiated and do not produce substantial amounts of catecholamines (in some patients, they produce only dopamine) compared with other hereditary subtypes, which enables these tumours to grow subclinically for a long time. In addition, SDHB pathogenic variants support tumour growth through high levels of the oncometabolite succinate and other mechanisms related to cancer initiation and progression. As a result, pseudohypoxia and upregulation of genes related to the hypoxia signalling pathway occur, promoting the growth, migration, invasiveness and metastasis of cancer cells. These factors, along with a high rate of metastasis, support early surgical intervention and total resection of PPGLs, regardless of the tumour size. The treatment of metastases is challenging and relies on either local or systemic therapies, or sometimes both. This Consensus statement should help guide clinicians in the diagnosis and management of patients with SDHB PPGLs.
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