Sense receptor

Ca2+ sensing receptor, a member of G-protein coupled receptors, is composed of seven transmembrane spanning domains. The extracellular domain contains clusters of negatively charged amino acids sensing even small fluctuations of extracellular calcium. Mutations in this receptor cause inheritable hypo- and hypercalcemic syndromes. 

Ca2+-sensing Receptor Calpains Protein Phosphates S100 Proteins... 

Calcium receptor Extracellular calcium-sensing receptor (CaSR)... 

The extracellular calcium Ca -sensing receptor plays a central role in maintaining a nearly constant level of extracellular calcium by sensing small changes in Ca and directly and/or indirectly altering the translocation of calcium ions into or out of the extracellular fluid so as to normalize CaQ+. Changes in the level of expression and/or function of the CaR reset the level of CaQ+. Recently developed activators (calcimimetics)... 

Hu J, Spiegel AM (2003) Naturally occurring mutations of the extracellular Ca2+-sensing receptor implications for its structure and function. Trends Endocrinol Metab 14 282-288... 

Tfelt-Hansen J, Brown EM (2005) The calcium-sensing receptor in normal physiology and pathophysiology a review. Crit Rev Clin Lab Sci 42(1 ) 3 5-70... 

A class of drugs that blocks the activation of the Ca2+-sensing receptor by extracellular Ca2+. 

A class of allosteric activators of the Ca2+-sensing receptor that sensitizes the receptor to extracellular calcium and acts only in the presence but not in the absence of calcium. Calcimimetics can be used to treat various forms of hyperparathyroidism, although they are only approved for use in patients with end stage renal disease receiving dialysis treatment. 

Proton-sensing GPCRs. Table 1 pH-sensing receptors... 

Extracellular Calcium-sensing Receptor (CaSR) Extracellular Matrix (ECM)... 

Naito T., Saito Y Yamamoto J., Nozaki Y., et al. (1998). Putative pheromone receptors related to the Ca2+-sensing receptor in Fugu. Proc Natl Acad Sci USA 95, 5178-5181. 

Not released from glands chemicals acting more quickly than hormones, but like them consequentially. Sometimes all the above set of messenger molecules are described under the endocrine system. Some are released by the peripheral sense receptors. There are many other possible hormones such as glucose and several of the simplest hormones are related to bacterial sensors e.g. NO and some ions (see Chapter 6). 

Cinacalcet reduces PTH secretion by increasing the sensitivity of the calcium-sensing receptor. The most common adverse events are nausea and vomiting. 

The mGluRs belong to family C of the GPCR superfamily, which also includes a calcium-sensing receptor (CaR), two y-aminobutyric acid type B (GABAb) receptors,... 

Pace, A. J., Gama, L and Breitwieser, G. E. (1999) Dimerization of the calcium-sensing receptor occurs within the extracellular domain and is eliminated by Cys— Ser mutations at Cys101 and Cys236. J. Biol. Chem. 274,11629-11634. 

Brauner-Osbome, H., Jensen, A. A., Sheppard, P. O., O Hara, P., and Krogsgaard-Larsen, P. (1999) The agonist-binding domain of the calcium-sensing receptor is located at the amino-terminal domain. J. Biol. Chem. 274,18382-18386. 

Zhang, Z., Sun, S., Quinn, S. J., Brown, E. M., and Bai, M. (2001) The extracellular calcium-sensing receptor dimerizes through multiple types of intermolecular interactions../. 

Jensen, A. A., Spalding, T. A., Burstein, E. S., et al. (2000) Functional importance of the Ala116-Pro136 region in the calcium-sensing receptor constitutive activity and inverse ago-nism in a family C G protein coupled receptor../. Biol. Chem. 275,29547-29555. 

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