Characterization of the effect of chronic administration of a calcium-sensing receptor antagonist, ronacaleret, on renal calcium excretion and serum calcium in postmenopausal women

Bone ◽  
2013 ◽  
Vol 56 (1) ◽  
pp. 154-162 ◽  
Author(s):  
Stephen Caltabiano ◽  
Colin T. Dollery ◽  
Mohammad Hossain ◽  
Milena T. Kurtinecz ◽  
John P. Desjardins ◽  
...  
2012 ◽  
Vol 27 (2) ◽  
pp. 255-262 ◽  
Author(s):  
Lorraine A Fitzpatrick ◽  
Christine E Dabrowski ◽  
Gregory Cicconetti ◽  
David N Gordon ◽  
Thomas Fuerst ◽  
...  

2020 ◽  
Vol 2020 ◽  
pp. 1-5
Author(s):  
Sachin K. Majumdar ◽  
Tess Jacob ◽  
Allen Bale ◽  
Allison Bailey ◽  
Jeffrey Kwon ◽  
...  

Familial hypocalciuric hypercalcemia (FHH) is considered a relatively benign condition characterized by mild elevations in serum calcium and relatively low urinary calcium excretion. It results from an elevated set point in serum calcium arising from variants in the calcium-sensing receptor (CaSR) gene but also AP2S1 and GNA11 genes, which encode for adaptor-related protein complex 2 and G11 proteins, respectively. The manifestations of FHH can vary and sometimes overlap with primary hyperparathyroidism making the diagnosis challenging. Case Presentations. We report a mother and daughter with a novel heterozygous variant in the CaSR gene resulting in a serine to leucine substitution at position 147 (S147L) of the CaSR. Both patients had mild hypercalcemia, relatively low urinary calcium excretion, elevated calcitriol, and low-to-normal intact PTH. The proband (daughter) presented with symptoms associated with hypercalcemia and was incidentally found to have a bony lesion suspicious for osteitis fibrosa cystica, and she was also diagnosed with sarcoidosis. Subtotal parathyroidectomy revealed normal-weight parathyroid glands comprised of 50–80% parathyroid epithelial cells, which has been documented as within the spectrum of normal. Her mother had no symptoms, and no intervention was pursued. Conclusion. We report a novel variant in the CaSR associated with FHH in two patients with similar biochemical features yet differing clinical manifestations. While the relationship of the bony findings and parathyroid histology with this variant remains unclear, these cases enrich our knowledge of CaSR physiology and provide further examples of how varied the manifestations of FHH can be.


2002 ◽  
Vol 87 (7) ◽  
pp. 3068-3073 ◽  
Author(s):  
Kohei Sato ◽  
Yukihiro Hasegawa ◽  
Jun Nakae ◽  
Kenji Nanao ◽  
Ikuko Takahashi ◽  
...  

Gain-of-function mutations of the calcium-sensing receptor (CaR) gene cause autosomal dominant and/or sporadic hypocalcemia with hypercalciuria. Because treatment of the hypocalcemia with vitamin D and/or calcium in patients with such mutations results in increased hypercalciuria, nephrocalcinosis, and renal impairment, its use should be limited to alleviating the symptoms of symptomatic patients. Because thiazide diuretics have been successfully used to treat patients with hypercalciuria and hypoparathyroidism, they are theoretically useful in reducing urine calcium excretion and maintaining serum calcium levels in patients with gain-of-function mutations of the CaR gene. In this study, we report on the clinical course, molecular analysis, and effects of hydrochlorothiazide therapy in two Japanese patients with gain-of-function mutations of the CaR gene. Within a few weeks after birth, they developed generalized tonic seizures due to hypocalcemia (serum calcium values: 1.1 mmol/liter and 1.3 mmol/liter, respectively). Despite treatment with the standard dose of 1,25-dihydroxyvitamin D3 in one patient and 1α-hydroxyvitamin D3 in the other, acceptable serum calcium levels near the lower limit of normal were not established, and their urinary calcium excretion inappropriately increased. Addition of hydrochlorothiazide (1 mg/kg) reduced their urinary calcium excretion and maintained their serum calcium concentrations near the lower limit of normal, allowing the 1,25-dihydroxyvitamin D3 and 1α-hydroxyvitamin D3 doses to be reduced, and it alleviated their symptoms. A heterozygous missense mutation was identified in both patients. In one patient, the mutation was A843E in the seventh transmembrane domain of the CaR, and in the other it was L125P in the N-terminal extracellular domain. In vitro transient transfection of their mutant CaR cDNAs into HEK293 cells shifted the concentration-response curve of Ca2+ to the left. In conclusion, two sporadic cases of hypercalciuric hypocalcemia were due to de novo gain-of-function mutations of the CaR gene. Hydrochlorothiazide with vitamin D3 successfully reduced the patients’ urinary calcium excretion and controlled their serum calcium concentrations and symptoms. Thiazide diuretics are effective in patients with gain-of function mutations of the CaR gene.


2016 ◽  
Vol 8 (3) ◽  
pp. 341-346 ◽  
Author(s):  
Anna Papadopoulou ◽  
Evangelia Gole ◽  
Katerina Melachroinou ◽  
Christos Meristoudis ◽  
Tania Siahanidou ◽  
...  

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