@article {KUREBE138, author = {MASARU KUREBE}, title = {Interaction of Dibucaine and Calcium Ion on a Calcium Pump Reconstituted from Defined Components of Intestinal Brush Border}, volume = {14}, number = {1}, pages = {138--144}, year = {1978}, publisher = {American Society for Pharmacology and Experimental Therapeutics}, abstract = {The uptake of Ca++ by reconstituted proteoliposomes involves an ATP-independent as well as an ATP-dependent process. In the presence of 0.7 mM ATP, 1 mM dibucaine inhibited Ca++ uptake and (Mg++ + Ca++)-ATPase activity, but 0.2 mM dibucaine stimulated both. The latter reduced the velocity of ATP-independent Ca++ uptake at low Ca++ concentrations, but increased it at a high concentration (0.15 mM of Ca++. ATP-dependent Ca++ uptake was facilitated by 0.2 mM dibucaine only in the presence of a high concentration of Ca++. Kinetic analyses of the data obtained with the lower dose of dibucaine suggest that this compound competes with Ca++ for binding sites on the outer surface of membranes and that its interaction with Ca++ induces a conformational change of membranes accompanied by an increase in the passive permeability of Ca++ and activation of the ATP-mediated Ca++ pump.}, issn = {0026-895X}, URL = {https://molpharm.aspetjournals.org/content/14/1/138}, eprint = {https://molpharm.aspetjournals.org/content/14/1/138.full.pdf}, journal = {Molecular Pharmacology} }