Biomaterial Database

Gap junctional conductance: comparison of sensitivities to H and Ca ions. 1982

D C Spray, and J H Stern, and A L Harris, and M V Bennett

One cytoplasmic aspect of the junctional membrane between coupled pairs of Fundulus blastomeres was perfused with solutions of known H and Ca ion concentrations. Conductance of junctional membrane was decreased by either ion. The sensitivity to H ions was about 10,000 times greater than that to Ca ions. The results suggest that junctional conductance can be modulated by changes in H ion concentration near physiological pH, but that unphysiologically high concentrations of Ca ion, such as would be reached only on cell death, are required for comparable changes in junctional conductance.

UI	MeSH Term	Description	Entries
D007365	Intercellular Junctions	Direct contact of a cell with a neighboring cell. Most such junctions are too small to be resolved by light microscopy, but they can be visualized by conventional or freeze-fracture electron microscopy, both of which show that the interacting CELL MEMBRANE and often the underlying CYTOPLASM and the intervening EXTRACELLULAR SPACE are highly specialized in these regions. (From Alberts et al., Molecular Biology of the Cell, 2d ed, p792)	Cell Junctions,Cell Junction,Intercellular Junction,Junction, Cell,Junction, Intercellular,Junctions, Cell,Junctions, Intercellular
D007695	Killifishes	Small oviparous fishes mostly in the family Cyprinodontidae but also some members of families Aplocheilidae, Fundulidae, Profundulidae, and Rivulidae. Some killifishes are used in mosquito control. Killifishes are vertebrate model organisms in various fields, e.g., environmental toxicology and neurobiology, because of their short lifespans, ease of maintenance and large number of eggs produced.	Cyprinodon,Cyprinodontidae,Pupfishes
D011522	Protons	Stable elementary particles having the smallest known positive charge, found in the nuclei of all elements. The proton mass is less than that of a neutron. A proton is the nucleus of the light hydrogen atom, i.e., the hydrogen ion.	Hydrogen Ions,Hydrogen Ion,Ion, Hydrogen,Ions, Hydrogen,Proton
D002118	Calcium	A basic element found in nearly all tissues. It is a member of the alkaline earth family of metals with the atomic symbol Ca, atomic number 20, and atomic weight 40. Calcium is the most abundant mineral in the body and combines with phosphorus to form calcium phosphate in the bones and teeth. It is essential for the normal functioning of nerves and muscles and plays a role in blood coagulation (as factor IV) and in many enzymatic processes.	Coagulation Factor IV,Factor IV,Blood Coagulation Factor IV,Calcium-40,Calcium 40,Factor IV, Coagulation
D002450	Cell Communication	Any of several ways in which living cells of an organism communicate with one another, whether by direct contact between cells or by means of chemical signals carried by neurotransmitter substances, hormones, and cyclic AMP.	Cell Interaction,Cell-to-Cell Interaction,Cell Communications,Cell Interactions,Cell to Cell Interaction,Cell-to-Cell Interactions,Communication, Cell,Communications, Cell,Interaction, Cell,Interaction, Cell-to-Cell,Interactions, Cell,Interactions, Cell-to-Cell
D002970	Cleavage Stage, Ovum	The earliest developmental stage of a fertilized ovum (ZYGOTE) during which there are several mitotic divisions within the ZONA PELLUCIDA. Each cleavage or segmentation yields two BLASTOMERES of about half size of the parent cell. This cleavage stage generally covers the period up to 16-cell MORULA.	Segmentation Stage, Ovum,Cleavage Stages, Ovum,Ovum Cleavage Stage,Ovum Cleavage Stages,Ovum Segmentation Stage,Ovum Segmentation Stages,Segmentation Stages, Ovum
D004553	Electric Conductivity	The ability of a substrate to allow the passage of ELECTRONS.	Electrical Conductivity,Conductivity, Electric,Conductivity, Electrical
D006863	Hydrogen-Ion Concentration	The normality of a solution with respect to HYDROGEN ions; H+. It is related to acidity measurements in most cases by pH	pH,Concentration, Hydrogen-Ion,Concentrations, Hydrogen-Ion,Hydrogen Ion Concentration,Hydrogen-Ion Concentrations
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia