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  • 1
    ISSN: 1434-0879
    Keywords: Idiopathic calcium urolithiasis ; Test meal Hyperinsulinaemia ; Insulin resistance ; Inappropriate phosphaturia ; Ascorbic acid effects
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract In idiopathic recurrent calcium urolithiasis (RCU) the state of insulin and carbohydrate metabolism, and relationships to minerals such as phosphate, are insufficiently understood. Therefore, in two groups of males with RCU (n = 30) and healthy controls (n = 8) the response to an oral carbohydrate- and calcium-rich test meal was studied with respect to glucose, insulin, and C-peptide in peripheral venous blood (taken before and up to 180 min post-load), and phosphate and glucose in fasting and post-load urine. In one RCU group (n = 16) the meal was supplemented with ascorbic acid (ASC; 5 mg/kg body weight). The mean age (RCU 29, RCU + ASC 30, controls 27 years) and mean body mass index [RCU 24.4, RCU + ASC 25.0, controls 24.0 kg/m2] were similar. Insulin resistance (synonymous sensitivity of peripheral organs to insulin) was calculated from insulin serum concentration, as was also integrated insulin, C-peptide, and glucose. Untreated stone patients (RCU) developed hyperinsulinaemia between 60 and 120 min post-load, increased integrated insulin, and insulin resistance (P ≤ 0.05 vs controls)., whereas the rise of C-peptide and glycaemia (absolute and integrated values) was only of borderline significance. Fasting phosphaturia was low in both RCU subgroups vs controls; however, phosphaturia in untreated RCU rose in response to the meal, contrasting sharply with a decrease in controls. ASC supplementation of the meal (in the RCU + ASC subgroup) normalized insulin, failed to normalize postload phosphaturia, but reduced post-load glucosuria and urinary pH significantly (mean pH values 5.55 vs 5.93 in untreated RCU, controls 5.50). Postprandial urinary oxalate, calcium, protein, and supersaturation products were not changed. The postprandial changes in phosphaturia and insulin sensitivity were inversely correlated (n = 38,r = -0.44,P = 0.007). It was concluded that in younger RCU males: (1) postprandial hyperinsulinaemia, the failure to reduce phosphaturia and —within limits — glucosuria, appropriately, as well as poor urine acidification are important features of the metabolism; (2) these phenomena are probably caused by insulin resistance of organs, the kidney included; and (3) the addition of a supraphysiological dose of ASC to a meal, the subsequent abolition of hyperinsulinaemia, and the restoration of normal urine acidification suggest that this antioxidant is capable of counteracting some preexisting basic abnormality of cell metabolism in RCU.
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  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Cellular and molecular life sciences 39 (1983), S. 425-427 
    ISSN: 1420-9071
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary We studied duodenal and ileal magnesium (Mg) absorption in intact, parathyroidectomized (PTX), thyroid-(TX) and thyroparathyroidectomized (TPTX) rats with iodine hormones replaced, and, additionally, in PTX rats receiving bovine parathyroid hormone 1–34 and 1,25-dihydroxyvitamin D3, respectively. Ma absorption was reduced after PTX and TPTX in the duodenum, but not in the ileum, whereas TX had no influence on duodenal or ileal Mg absorption. Both bovine parathyroid hormone 1–34 and 1,25-dihydroxyvitamin D3 increased Mg absorption in the duodenum and the ileum in PTX rats.
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  • 3
    ISSN: 1420-9071
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Zusammenfassung Unter Zwangshaltung entwickeln intakte, scheinoperierte und adrenalektomierte Ratten eine Drosselung der Magenperfusion und unterschiedlich häufig Nekrosen und Erosionen in der Magenmukosa. Dieses Phänomen ist von einem erheblichen Anstieg an Pankreasglucagon begleitet, während Gastrin unter Stress eher abfällt.
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  • 4
    ISSN: 1432-0827
    Keywords: Key words: Gastric fundectomy — Hypergastrinemia — Calciotropic hormones — Bone — Mineral homeostasis.
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Abstract. In humans, gastric surgery results in in osteopenia via mechanisms that are insufficiently understood; surgery-induced changes in the hormonal axes involving the stomach, thyroid, and the parathyroids may play a role. To study this in more detail, we evaluated calcium (Ca), magnesium (Mg), and phosphorus (P) metabolism as well as physical, chemical, and histomorphometric bone parameters in rats rendered hypergastrinemic by fundectomy (FX). In independent experiments, the response to an oral Ca challenge was investigated in intact rats versus FX, and in thyroidectomized versus thyroid-intact FX rats. Sixteen weeks following FX, body weight was approximately 80% that of sham-operated controls. In urine, P excretion was elevated fivefold, the pH was significantly decreased, and cAMP excretion was elevated as compared with controls; serum parathyroid hormone (PTH), calcitonin, 25OHD, Ca, Mg, and P were normal; gastrin and 1,25(OH)2D were elevated. On the basis of bone ash mineral content, FX rats developed significant osteopenia, and histomorphometry indicated only slightly elevated bone turnover and mineralization. Following oral Ca, thyroid-intact FX rats developed hypercalcemia, serum gastrin decreased, and calcitonin increased significantly; in thyroidectomized FX rats, calcitonin remained at baseline levels although there was a similar degree of hypercalcemia; PTH decreased during the hypercalcemic period in both groups. Serum gastrin did not correlate with calcitonin or PTH, and in multivariate regression analysis the only predictor of serum 1,25(OH)2D was urinary phosphorus. It was concluded that in the FX rat (1) osteopenia is not caused by intestinal Ca malabsorption, vitamin D, Ca deficiency, or secondary hyperparathyroidism; (2) osteopenia may be related to PTH-independent urinary hyperexcretion of P, followed by a rise of serum 1,25(OH)2D; (3) the existence of endocrine axes among gastrin, calcitonin, and PTH cannot be substantiated. FX osteopenia appears to be related to gastric acid abolition, and the reactive hypergastrinemia probably stabilizes the mass and turnover of bone.
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  • 5
    ISSN: 1432-1440
    Keywords: Jejuno-ileal bypass ; Extreme obesity ; Mineral metabolism ; Jejuno-ilealer Bypass ; extreme Fettsucht ; Mineralstoffwechsel
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Bei morbider Adipositas wurde der Einfluß der jejuno-ilealen Bypass-Operation auf den Mineralstoffwechsel untersucht. Mit postoperativer oraler Calcium- und Kalium-Substitution blieben 2 und 5 Jahre nach Bypass-Operation im Serum die Calcium-Fraktionen, Parathormon, Phosphat, Kalium und der Knochenmineralgehalt unverändert, während Serum-Magnesium abfiel. Serum-25-Hydroxyvitamin D war bereits präoperativ niedrig und blieb so postoperativ. Nach der Operation stieg die Urinausscheidung von Oxalat bis in den oberen Normbereich an, während diejenige von Calcium, Magnesium und Citrat stark abfiel. Das Aktivitätsprodukt von Calciumoxalat im Urin blieb unverändert, während das von Brushit abfiel. Da diese Veränderungen im Urin aller Patienten nachweisbar waren, bleiben die Ursachen der postoperativen Steinbildung bei 4 von 19 Patienten zur Zeit unklar. Wir folgern, daß die Empfehlung zur präzisen oralen Calcium-Substitution nach jejuno-ilealem Bypass gerechtfertigt erscheint, weil dadurch langfristige ernste Störungen des Calcium-Stoffwechsels vermieden, außerdem die intestinale Oxalat-Absorption reduziert werden.
    Notes: Summary The influence of jejuno-ileal bypass surgery on mineral metabolism was studied in patients with morbid obesity before operation, and 2 and 5 years after-wards. When calcium and potassium were orally substituted post-operatively, in serum calcium fractions, parathyroid hormone, phosphate, potassium and the bone mineral content remained unchanged, while serum magnesium decreased. Serum 25-hydroxyvitamin D was already low before bypass operation, and did not change thereafter. Post-operatively, the urinary excretion of oxalate rose into the upper normal range, while that of calcium, magnesium and citrate was markedly reduced. The urinary activity product of calcium oxalate rose slightly, but that of brushite decreased. Since these changes were manifest in the urine of all patients, the reasons for the post-operative formation of renal stones in 4 of 19 patients remain unclear at the moment. We conclude that the recommendation for precise oral calcium substitution after jejuno-ileal bypass operation seems justified in order to avoid serious disturbances of calcium metabolism in the long term, and to reduce intestinal oxalate absorption.
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  • 6
    ISSN: 1432-1440
    Keywords: Urolithiasis subgroups ; Parathyroid hormone ; Blood and urine ; Cyclic AMP ; Cyclic GMP ; Nephrogenous nucleotides ; Urolithiasis-Untergruppen ; Parathormon ; Blut und Urin ; Zyklisches AMP ; Zyklisches GMP ; Nephrogene Nukleotide
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Bei Gesunden (n=34) und Urolithiasis-Patienten mit den verschiedenen definierten metabolischen Untergruppen, einschließlich primärer Hyperparathyreoidismus (pHPT), wurden Parathormon (PTH) mittels zwei verschiedenen Antikörpern, sowie zyklische Nukleotide (cAMP; cGMP im Urin und Plasma studiert, außerdem deren nephrogene Komponente berechnet. Bei Nicht-pHPT-Steinkrankheit (=sog. idiopathische Form) war das nephrogene cAMP (2 h-Nüchternurin) bei der normocalciurisch verlaufenden Mehrheit (n=60) signifikant niedriger als normal, und auch in den anderen Untergruppen (absorptive Hypercalciurie,n=15; renale Hypercalciurie,n=23; Harnsäure-Lithiasis,n=17; Harnsäure/Calciumoxalat-Lithiasis,n=12) waren die Medianwerte niedriger als jener der Kontrollgruppe. Umgekehrt ist nephrogenes cAMP bei pHPT (n=20) stark erhöht, und nur bei dieser Störung war nephrogenes cGMP (2 h-Urin) ebenfalls erhöht. Die gesamte Nukleotid-Produktion (=Summe der nephrogenen Anteile von cAMP und cGMP) ist bei normocalciurisch verlaufender Steinkrankheit signifikant erniedrigt, bei pHPT erhöht. Ausgenommen hohes cAMP bei pHPT sind die Plasma-Nukleotide nicht verschieden. Steinpatienten (idiopathisch und pHPT) haben gemeinsam ein signifikant niedrigeres Serum-Phosphat und eine niedrigere Phosphatschwelle als Gesunde. Ausgenommen pHPT sind die Unterschiede in allen Gruppen beim Serum-Gesamtcalcium nur minutiös, ionisiertes Calcium ist bei renaler Hypercalciurie innerhalb des Normbereiches mäßig erhöht. PTH ist in allen Untergruppen der idiopathischen Lithiasis entweder normal bis niedrig (assay für intaktes Hormon) oder in einigen (absorptive und renale Hypercalciurie, alternativ Harnsäure oder Calcium-Oxalat-bildende Patienten) gering, aber signifikant erhöht (assay für mittlere bioinaktive Hormonregion). Mit den gleichen Bestimmungsmethoden ist das mediane PTH bei operativ bewiesenem pHPT um Faktor 8 bzw. 3 höher als bei gesunden Kontrollen. Aus den Ergebnissen wird gefolgert, daß a) die idiopathische Harnsteinkrankheit mit normaler bis niedriger renaler Bioaktivität der Nebenschilddrüsen einhergeht und diese Patienten bei normal-niedrigem Urin-cAMP eine niedrige renale Phosphatschwelle unbekannter Ätiologie aufweisen; b) das bei drei Untergruppen erhöhte Serum-PTH, gemessen mit einem Antikörper mit vorrangiger Erkennung der bio-inaktiven mittleren Hormonregion, nicht mit dem gleichzeitig normalen Urin- bzw. nephrogenen cAMP dieser Gruppen übereinstimmt, wohl aber mit normalem oder niedrigem PTH, gemessen mit einem assay, der alle Anteile des menschlichen Hormons erkennt; c) die Aktivität der tubulären Guanylat-Zyklase bei pHPT wahrscheinlich gesteigert ist, nicht jedoch in Abwesenheit von Hypercalcämie oder größerem PTH-Exzeß (übrige Gruppen).
    Notes: Summary In healthy controls (n=34) and in the various metabolically defined subgroups of urolithiasis patients, including primary hyperparathyroidism (pHPT), parathyroid hormone (PTH) was studied using two different antisera, as were the cyclic nucleotides (cAMP; cGMP) and related variables in both urine and plasma; in addition, the nephrogenous components of the cyclic nucleotides were also determined. In nonpHPT (so-called idiopathic) stone disease, nephrogenous cAMP (2-h fasting urine) was significantly lower than normal in the normo-calciuric majority (n=60), and also lower than normal (medians) in all the other subgroups (absorptive hypercalciuria,n=15; renal hypercalciuria,n=23; uric acid lithiasis,n=17; uric/calcium oxalate lithiasis,n=12). In contrast, it was significantly elevated in pHPT (n=20), and only in this latter condition was nephrogenous cGMP (2-h urine) elevated. The total nucleotide production (sum of nephrogenous cAMP + nephrogenous cGMP) is again significantly lower only in normo-calciuric calcium stone disease. Except for high values in pHPT, no differences in plasma nucleotides are observed. Stone patients (idiopathic and pHPT) have significantly lower-than-normal serum phosphate and phosphate threshold in common. With the exception of pHPT, the differences in serum calcium are only minute, while ionised calcium is moderately elevated within the normal range in the serum of renal hypercalciuria patients. In all subgroups of idiopathic lithiasis, PTH is either normal to low (intact hormone assay), or slightly but significantly elevated in three subgroups (absorptive and renal hypercalciuria, patients alternately forming uric acid or calcium oxalate stones), when measured in an assay recognizing only a bioinactive hormone fragment (mid-portion assay). In surgically proven pHPT, median PTH established with the same two assays, is elevated by a factor of 8 (intact hormone assay), or 3 (mid-portion assay) in comparison with healthy controls. From the results it is concluded that a) idiopathic urolithiasis is accompanied by normal or low renal bioactivity of the parathyroid glands in the presence of a low renal phosphate threshold concentration; b) the elevated serum PTH in three idiopathic subgroups measured with an antibody with recognition largely of the bioinactive mid-portion of the hormone, is not in accordance with the simultaneously normal or low urinary and nephrogenous cAMP of these individuals, but is in accord with the normal or low serum PTH measured with an antibody recognizing all regions of the human hormone; c) the activity of tubular guanylate cyclase in pHPT is probably increased, but not in situations where both hypercalcemia and a considerable excess of parathyroid hormone are absent (remaining groups).
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  • 7
    ISSN: 1432-1440
    Keywords: Duodenal ulcer ; Controls ; Urinary minerals ; Urinary oxalate and citrate ; Highly selective vagotomy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The urinary excretion of calcium, oxalate, citrate and magnesium, and the relative saturation products in urine of either calcium oxalate or calcium phosphate, were determined in male duodenal ulcer (DU) patients preoperatively (n=60), and 1 and 5 years following highly selective vagotomy (HSV), and in male healthy controls (n=30). In DU before HSV citrate and magnesium were lowered, oxalate was in the low normal range and calcium was normal. The calcium oxalate product was lower than in controls, while the calcium phosphate product was unchanged. Within 5 years HSV normalized urinary citrate and oxalate, but not urinary magnesium, and the median urinary pH was lower than pre-operatively. There thus results a normal product for calcium oxalate, but a reduced one for calcium phosphate. It is suggested that: (1) unoperated DU patients have a urine composition similar to that cxhibited in normocalciuric recurrent calcium urolithiasis; (2) this spectrum of urinary constituents may be changed by HSV.
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  • 8
    Electronic Resource
    Electronic Resource
    Springer
    Journal of molecular medicine 62 (1984), S. 595-597 
    ISSN: 1432-1440
    Keywords: Plasma somatostatin ; Islet hormones ; Biliary stone patients ; Control subjects
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary We have searched for elevated basal plasma somatostatin in patients with documented cholelithiasis (n=37) and compared the data with healthy control subjects (n=27). Using an acidic assay system for measuring somatostatin in unprocessed plasma, we could not find deviations from normal values in biliary stone patients. Also basal blood levels of other islet cell hormones (insulin, glucagon) and minerals (calcium, magnesium) are unchanged. Further studies are needed to find out whether an abnormal response of plasma somatostatin to appropriate stimuli can play a role in the etiology of biliary stones.
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  • 9
    Electronic Resource
    Electronic Resource
    Springer
    Research in experimental medicine 165 (1975), S. 291-296 
    ISSN: 1433-8580
    Keywords: rat models ; stress ulcers ; calcitonin prophylaxis ; mucosal pO2 ; glucagon ; gastrin ; serum calcium ; ulcer index
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary During restraint stress (24 h) various rat models exhibit differences in ulcer index, a decrease in gastric perfusion (pO2), serum gastrin and calcium, but increased pancreatic glucagon. Prophylaxis by calcitonin prevents gastrin from falling, improves markedly ulcer index in intact, sham-operated and thyroparathyroidectomized rats, is ineffective following parathyroidectomy and augments stress sensivity following thyroidectomy. It is suggested that, in the presence of exogenous calcitonin, both vulnerability of gastric mucosa and responsiveness of pancreatic alpha cells largely depend on concentration of extracellular calcium and availability of endogenous thyroidal calcitonin and parathyroid hormone.
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  • 10
    ISSN: 1433-8580
    Keywords: gastric stress ulcer ; mucosal oxygen tension ; vagotomy/splanchnicotomy ; secretin ; gastrin/glucagon
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Restraint stress ulcers in rats were developed and procedures evaluated designed at preservation of intact gastric microcirculation (pO2). Neither prior truncal vagotomy, splanchnicotomy nor combined dissection of abdominal autonomic nerves were effective in preventing the stress mediated fall of mucosal pO2 and the rise in plasma glucagon. The ulcer index remained elevated and gastrin essentially was unchanged. Prophylactic injection of increasing doses (1, 2, 4, 8, 16 U/kg) secretin maintained microcirculation at pO2-levels subnormal for unstressed animals (Vmax 15.53 mm Hg; Km. 0.99 U/kg), but simultaneously brought about a continuous rise in serum gastrin. Up to 8 U/kg plasma glucagon was higher than in saline control groups reaching a peak value with 2 U/kg when ulcer index showed its nadir. Secretin therapy (4, 8 U/kg) markedly improves both mucosal pO2 and ulcer index. It is suggested that breakdown of gastric microcirculation may not be solely responsible for stress ulcer development.
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