Ca2+ sensing system

The rate of exocytosis from any type of cell is a very important factor and is therefore subject to strict regulation. This rate can be changed through the modification of different parameters of the exocytotic machinery. Analysis of pancreatic /J-cells shows that the latency time in the Ca2+ sensing system of the exocytotic machinery and the clustering of channels on the cell surface may be two convenient targets for adjusting the rate of the release of hormones or neurotransmitters from cells. 

Ca2+ sensing by 1 can be understood by considering a PET process originating in the Ca2+-free tetracarboxylate receptor and the linearly fused tricyclic system. The rapidity of the process may be ascribed to the low oxidation potential of the electron rich alkoxyaniline donor and to the short distance of separation between the two transfer components. The minimal separation arranged by a virtual spacer of zero carbon atoms is worthy of note. A low level of luminescence is seen owing to the fast PET. 

Ca2+, and it is a typical example of the power of the combinatorial method. Because of the ease of generating different sensing system pairs, it requires a minimal effort to synthesize layers with these small variations, which would usually be disregarded in solution state receptor synthesis. 

Solubilities of annealed skeletal carbonates were estimated by Land (1967) by allowing the system to reach a steady state pH and by determining dissolved Ca2+ and Mg2+ concentrations. Dissolution of the magnesian calcites in Land s experiments appeared to be congruent in the sense that the steady state solution had a molar Ca2+/Mg2+ ratio similar to that of the solid. 

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