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Factors modulating the response of a porcine renal tubular cell line to calcitonin and antidiuretic hormone.

A cell line (LLC-PK1) isolated from porcine kidney increases 3'5'-cyclic adenosine monophosphate (cAMP) content when incubated with salmon calcitonin (SCT) or antidiuretic hormone (ADH). We have examined several factors which modulate the hormone-induced changes in cAMP levels in these cells. Preincubation with increasing concentrations of SCT results in a dose-dependent decrease in cAMP levels in cells retested with this hormone. Addition of 3-isobutyl-l-methylxanthine (IBMX) to cells preincubated with SCT results in 15--30-fold increases in cAMP levels compared to cells preincubated without …

Calcitonin-like immunoreactivity in rat and human pituitary glands: histochemical, in vitro, and in vivo studies.

This study was designed to determine whether pituitary glands contain an immunoreactive material which reacts with antisera to calcitonin (CT) and, if so, whether secretion of the material could be demonstrated. Testing 15 antisera to rat and human CT and using an immunoperoxidase method, we found 2 antisera to human CT which stained rat pituitaries and several which stained human pituitaries. Essentially all cells in the rat intermediate lobe and scattered cells in the rat and human anterior lobes showed staining, and staining was not entirely abolished by prior adsorption of antisera with ra…

ACTH, ADH, and calcitonin concentrations as markers of response and relapse in small-cell carcinoma of the lung.

The ectopically produced polypeptide hormones ACTH, ADH, and calcitonin were investigated as tumor markers in patients with small-cell carcinoma of the lung (SCC). Plasma ADH concentrations were evaluated separately as well as in relation to concomitantly obtained plasma osmolality levels. No significant nor consistent changes of marker concentrations caused by lysis of tumor cells were found immediately after administration of cytotoxic drugs. After tumor regression, plasma ACTH and serum calcitonin concentrations and inappropriate ADH secretion (plasma ADH levels inappropriately high compare…

Small cell carcinoma of the lung: relation of calcitonin to bone marrow metastases, parathormone and gastrin.

The relations of calcitonin concentrations to the presence of bone marrow metastases and to the concentrations of calcium, parathormone and gastrin in serum were investigated in 74 untreated patients with small cell carcinoma of the lung. Calcitonin concentrations were enhanced in two thirds of the patients, while serum calcium concentrations were normal in all. In 19 of 57 patients parathormone concentrations were slightly above the normal range, but the concentrations of parathormone and calcitonin were not correlated. Bone marrow metastases had no influence on the concentration of serum cal…

Bone matrix studies. Influences of parathyroid extract, calcitonin, and cholecalciferol and of rickets and its treatment.

Bones from young rats were incubated with radioactive glucosamine and proline. The concentrations and specific activities of matrix glycosaminoglycan fractions, prepared by a cetylpyridinium chloride method, and the specific activity of insoluble collagen hydroxyproline were determined. Acute parathyroid extract treatment increased labelling of hyaluronic acid and a glycopeptide fraction. These effects were partially blocked by calcitonin treatment which had no effect by itself. Parathyroid extract inhibited collagen synthesis and this effect was not blocked by calcitonin. Effects of these two…

Does salmon calcitonin influence the motility of the human gastrointestinal tract? An electromanometric and endoscopic study.

The effect of salmon calcitonin--as a relatively high dose of 25 mug by single iv. injection--upon the basal and metoclopramide-stimulated motility phenomena of the stomach and proximal duodenum as well as upon the unstimulated colon and rectosigmoid was evaluated in 12 subjects without gastrointestinal disease by quantitative electromanometric measurements performed for one hour with the aid of fluid-filled micro-balloon-catheter-systems. Additionally, in 9 subjects the reaction of the cardia, stomach, pylorus and proximal duodenum upon the same dose of the hormone was observed endoscopically…

Effects of synthetic salmon calcitonin on gastric secretion and ulcer formation in conscious cats and rats.

In conscious and unrestrained cats the gastric secretion and ulcer formation induced by i.v. infusion of pentagastrin can be inhibited by synthetic salmon calcitonin given simultaneously. The volume and various constituents of gastric juice are proportionally diminished. Pepsin alone is definitely more inhibited, which may be of significance in respect to the mode of action of calcitonin. These effects are dose dependent in the range of 0.01 mug - 1.0 mug/kg/h salmon calcitonin, corresponding to 0.05 - 5.0 MRC units. Based on the finding that such minute doses have effects, it may be speculate…

Paradoxical effect of salmon calcitonin on serum calcium: studies in intact and thyroparathyroidectomized men and dogs.

Total serum calcium of normal men, a hypoparathyroid man, two thyroparathyroidectomized men, and intact and thyroparathyroidectomized dogs were studied at multiple intervals following the acute administration of synthetic salmon calcitonin. Calcitonin produced marked fluctuations in serum calcium in one normal man and a biphasic hypocalcaemic response in another. In four of five intact dogs, calcitonin caused absolute or relative hypercalcaemia. In contrast, administration of calcitonin to thyroparathyroidectomized dogs caused a hypocalcaemia with less fluctuations and with no periods of hyper…

[Calcitonin measurement in fine needle aspiration washout fluid : when biology arbitrates between two cytological diagnoses].

Medullary thyroid carcinoma is a lesion whose preoperative diagnosis mainly relies on serum calcitonin measurement and cytology obtained by fine-needle aspiration. A marked elevation of calcitonin during the evaluation of a thyroid nodule constitutes a warning signal. The sensitivity of cytology is limited because of the tumor's morphological heterogeneity. Measurement of calcitonin in the washout fluid from the aspiration needle and syringe significantly improves diagnostic performance, both for thyroid nodules and for suspicious lymph nodes. This clinical vignette illustrates the importance …

Arterial hypertension: A safety risk of calcitonin gene-related peptide ligand and receptor blocker class.

OBJECTIVE: To identify and analyze adverse event reports of arterial hypertension (hereinafter referred as hypertension) associated with calcitonin gene-related peptide (CGRP) ligand (L) and receptor (R) blockers. BACKGROUND: CGRP is a potent peripheral and cerebral vasodilator and plays a key role in the pathogenesis of migraine. The US Food and Drug Administration (FDA) previously identified postmarketing case reports of hypertension associated with erenumab resulting in an amendment of the US Prescribing Information. However, at that time, no hypertension safety signal was apparent for oth…

Enteric glia, neuropeptides, and Parkinson's: impacts of calcitonin gene-related peptide on gut alpha synuclein.

Parkinson's disease is a neurodegenerative disorder pathologically characterized by accumulation of misfolded α-synuclein in the central and peripheral nervous systems, influencing symptomology at both sites. Calcitonin gene-related peptide (CGRP), a neuropeptide produced in the brain and intestine, has been linked with altered α-synuclein aggregation. This study examines the role of calcitonin gene-related peptide in modulating enteric α-synuclein accumulation and enteric glial cell reactivity using an ex vivo slice culture model from A53T+/- human α-synuclein mutant mice. In slices treated w…

Both single mutation and molecular conjugation on the mutant prevent calcitonin from forming amyloid fibrils.

Human calcitonin (hCT) is a peptide hormone made up of 32 amino acids, produced by the parafollicular cells of the thyroid gland. Its main role is to decrease blood calcium levels by inhibiting osteoclast activity and reducing calcium reabsorption in the kidneys and intestines. This characteristic positions hCT as a potential treatment for bone-related conditions, such as osteoporosis and Paget's disease. However, hCT has a strong tendency to form amyloid fibrils, which can lead to a loss of its biological function. This research aims to stabilize hCT's conformation through molecular conjugati…

Intrarectal Antagonism of Calcitonin Gene-Related Peptide Prevents Spinal Cord Injury-Associated Neurogenic Bowel Phenotypes.

Neurogenic bowel (NB) affects roughly 60% of people with a spinal cord injury (SCI), and these patients present with slow colonic transit, constipation, and chronic abdominal pain. The mechanisms by which NB bowel develops are unclear, thereby limiting interventions to being primarily symptom-focused and ineffective. Therefore, the main goal of this study was to identify the mechanisms that initiate and maintain NB after SCI as a critical step to develop evidence-based, novel therapeutic options to prevent NB. In previous studies, the neurogenic inflammatory mediator calcitonin gene-related pe…

Половые особенности участия пептида кальцитонина, связанного с геном, сигнализирующего о боли в экспериментальном аутоиммунном энцефаломиелите.

ВВЕДЕНИЕ: Нейропическая боль (НФ) является одним из наиболее разрушительных и недостаточно управляемых симптомов множественного склероза (МС). В его нынешнем виде NP - это трудное состояние, которое нужно лечить, поскольку многие широко используемые методы болеутоляющего лечения неэффективны. В настоящее время проводятся исследования, свидетельствующие о гендерных различиях в механизме NP в MS, что усложняет поиск новых методов лечения. Хотя широко известно, что пациенты-женщины чаще, чем пациенты-мужчины, развивают СС, в меньшей степени признается тот факт, что у них также более высока вероят

Совпадение в аннотации оригинала
INTRODUCTION: Neuropathic pain (NP) is one of the most devastating and under-managed symptoms of multiple sclerosis (MS). As it stands, NP i … d EAE both in vitro and in vivo, as well as increased antibody stain intensity for the neuropeptide calcitonin gene-related peptide (CGRP). Using a receptor antagonist for CGRP (CGRP8-37), we were able to reverse spontaneous pain in female EAE animals. CONCLUSIONS: These results suggest that targeting peptidergic nociceptors and CGRP signaling, specifically …

Calcitonin-Gene-Related Peptide in Migraine and Tension-Type Headache in Children During Interictal Period.

Background/Objectives: Research on calcitonin-gene-related peptide (CGRP) in adult migraine is extensive, but its role in childhood migraine remains unclear. This study aimed to evaluate serum CGRP levels in children experiencing migraine and tension-type headache (TTH) during interictal periods, comparing these levels to age-matched healthy controls. Methods: A total of 66 migraine patients, 59 with TTH, and 53 controls were recruited and stratified by headache onset age: under 7, 7-12, and over 12 years. CGRP levels were quantified using enzyme-linked immunosorbent assay (ELISA). Results: Th…

Characterization of trigeminal C-fiber reactivity through capsaicin-induced release of calcitonin gene-related peptide.

OBJECTIVE: We hypothesized that the response of trigeminal dermal blood flow (DBF) in the trigeminal system and consecutive expansion of flare response to capsaicin would differ from the somatosensory system (arm). We also investigated whether there are differences between patients with migraine and healthy controls (HC). BACKGROUND: Functional differences between the trigeminal and extracephalic somatosensory systems may partly explain the susceptibility for headaches in patients with migraine. Capsaicin-induced activation of nociceptive C-fibers in the skin is mainly mediated by calcitonin …

Calcitonin Gene-Related Peptide (CGRP) and Pituitary Adenylate Cyclase-Activating Polypeptide (PACAP) in Migraine Pathogenesis.

Migraine is a prevalent and debilitating neurologic disorder. Advancements in understanding the underlying pathophysiological mechanisms are spearheading the effort to introduce disease-specific treatment options. In recent years this effort has largely focused on alteration of endogenous neuropeptide signaling, namely the peptides calcitonin gene-related peptide (CGRP) and pituitary adenylate cyclase-activating polypeptide (PACAP). Human studies into the pathophysiological underpinnings of CGRP and PACAP in migraine are manifold and here we review the works investigating these neuropeptides i…

Case Report: A Challenging Clinical Problem of Calcitonin-Negative Medullary Thyroid Cancer Diagnosis and Surveillance.

Medullary carcinoma of the thyroid is a rare neuroendocrine carcinoma that originates from the malignant proliferation of parafollicular C cells. In almost 100% of the cases, medullary carcinoma of the thyroid is associated with high levels of calcitonin and carcinoembryonic acid (CEA). Both carcinoembryonic antigen and calcitonin are used for the diagnosis and surveillance of medullary carcinoma of the thyroid. Calcitonin-negative medullary carcinoma of the thyroid is an extremely rare entity that is characterized by classic medullary carcinoma of the thyroid morphology without raised serum c…