In vitro perifusion for the study of parathyroid hormone secretion: Effects of extracellular calcium concentration and beta-adrenergic regulation on bovine parathyroid hormone secretion in vitro

1980 ◽  
Vol 32 (1) ◽  
pp. 19-27 ◽  
Author(s):  
David A. Hanley ◽  
Kensuke Takatsuki ◽  
Maria E. Birnbaumer ◽  
Arthur B. Schneider ◽  
Louis M. Sherwood
Keyword(s):  
Parathyroid Hormone ◽  
Calcium Concentration ◽  
Hormone Secretion ◽  
Extracellular Calcium ◽  
Beta Adrenergic ◽  
Adrenergic Regulation ◽  
Extracellular Calcium Concentration ◽  
Bovine Parathyroid Hormone

scholarly journals Calcium and Spike Timing-Dependent Plasticity

2021 ◽  
Vol 15 ◽  
Author(s):  
Yanis Inglebert ◽  
Dominique Debanne
Keyword(s):  
Synaptic Plasticity ◽  
Calcium Concentration ◽  
Calcium Influx ◽  
Spike Timing ◽  
Extracellular Calcium ◽  
Dependent Plasticity ◽  
Extracellular Calcium Concentration ◽  
Activity Dependent

Since its discovery, spike timing-dependent synaptic plasticity (STDP) has been thought to be a primary mechanism underlying the brain’s ability to learn and to form new memories. However, despite the enormous interest in both the experimental and theoretical neuroscience communities in activity-dependent plasticity, it is still unclear whether plasticity rules inferred from in vitro experiments apply to in vivo conditions. Among the multiple reasons why plasticity rules in vivo might differ significantly from in vitro studies is that extracellular calcium concentration use in most studies is higher than concentrations estimated in vivo. STDP, like many forms of long-term synaptic plasticity, strongly depends on intracellular calcium influx for its induction. Here, we discuss the importance of considering physiological levels of extracellular calcium concentration to study functional plasticity.

Defective regulation of the cytosolic Ca2+ activity in parathyroid cells from patients with hyperparathyroidism

1984 ◽  
Vol 4 (11) ◽  
pp. 909-915 ◽  
Author(s):  
Rolf Larsson ◽  
Chris Wallfelt ◽  
Håkan Abrahamsson ◽  
Erik Gylfe ◽  
Sverker Ljunghall ◽  
...  
Keyword(s):  
Parathyroid Hormone ◽  
Calcium Concentration ◽  
Close Correlation ◽  
Extracellular Calcium ◽  
Hormone Release ◽  
Extracellular Calcium Concentration ◽  
The Individual ◽  
Release Characteristic ◽  
In Cells

The parathyroid hormone (PTH) release and cytosolic Ca2+ activity were determined in normal bovine parathyroid cells and parathyroid cells obtained from patients with hyperparathyroidism (HPT). There was a sigmoid relation between the cytosolic Ca2+ activity and the extracellular calcium concentration between 0.5 and 6.0 mmol/l. The PTH release was inhibited in parallel with the rise in the cytosolic Ca2+ activity. Both the hormone release and the cytosolic Ca2+ activity were lower in cells from human adenomas and hyperplastic glands∼ and in comparison with the bovine preparations these ceils had higher set points for the cytosolic Ca2+ activity and PTH release. There was a close correlation between the individual set points for the cytosolic Ca2+ activity and PTH release in a material containing both normal and pathological cells. The results indicate that the abnormal PTH release characteristic of HPT is due to a defective regulation of the cytosolic Ca2+ activity.

scholarly journals Rare diseases caused by abnormal calcium sensing and signalling

Endocrine ◽  
2021 ◽  
Vol 71 (3) ◽  
pp. 611-617
Author(s):  
Judit Tőke ◽  
Gábor Czirják ◽  
Péter Enyedi ◽  
Miklós Tóth
Keyword(s):  
Calcium Homeostasis ◽  
Calcium Concentration ◽  
Gene Mutations ◽  
Cell Types ◽  
Bartter Syndrome ◽  
Extracellular Calcium ◽  
Calcium Signal ◽  
Extracellular Calcium Concentration ◽  
Calcium Sensing ◽  
Increased Risk

AbstractThe calcium-sensing receptor (CaSR) provides the major mechanism for the detection of extracellular calcium concentration in several cell types, via the induction of G-protein-coupled signalling. Accordingly, CaSR plays a pivotal role in calcium homeostasis, and the CaSR gene defects are related to diseases characterized by serum calcium level changes. Activating mutations of the CaSR gene cause enhanced sensitivity to extracellular calcium concentration resulting in autosomal dominant hypocalcemia or Bartter-syndrome type V. Inactivating CaSR gene mutations lead to resistance to extracellular calcium. In these cases, familial hypocalciuric hypercalcaemia (FHH1) or neonatal severe hyperparathyroidism (NSHPT) can develop. FHH2 and FHH3 are associated with mutations of genes of partner proteins of calcium signal transduction. The common polymorphisms of the CaSR gene have been reported not to affect the calcium homeostasis itself; however, they may be associated with the increased risk of malignancies.

scholarly journals Magnesium modulates parathyroid hormone secretion and upregulates parathyroid receptor expression at moderately low calcium concentration

2013 ◽  
Vol 29 (2) ◽  
pp. 282-289 ◽  
Author(s):  
M. E. Rodriguez-Ortiz ◽  
A. Canalejo ◽  
C. Herencia ◽  
J. M. Martinez-Moreno ◽  
A. Peralta-Ramirez ◽  
...  
Keyword(s):  
Parathyroid Hormone ◽  
Calcium Concentration ◽  
Hormone Secretion ◽  
Receptor Expression ◽  
Low Calcium
Sign in / Sign up

Export Citation Format

Share Document