Biomaterial Database

Evidence for Na+/Ca2+ exchange in isolated smooth muscle cells: a fura-2 study. 1987

K Pritchard, and C C Ashley

University Laboratory of Physiology, Oxford, Great Britain.

Isolated smooth muscle cells (SMC) from guinea pig taenia coli were employed. Suspension of cells were externally loaded in saline with the fluorescent calcium indicators quin-2/AM or fura-2/AM at 20-40 microM or 4 microM respectively, resulting in an estimated intracellular concentration of 100-200 microM for quin-2 or 10-20 microM fura-2 (free acid). On addition of 100 microM carbachol or high K+o (80 mM) depolarization, fura-2 loaded cells contracted (104 +/- 47 micron, n = 121 rest: 39 +/- 13 micron, n = 59 contracted) identically to control (103 +/- 35 micron, n = 232 rest: 39 +/- 16 micron, n = 89 contracted) cells, whereas quin-2 loaded cells were unresponsive to these protocols and there was no significant length change. The Ca2+i of fura-2 loaded cells was 100 +/- 18 nM (mean +/- SD, n = 15) and was not significantly different from quin-2 loaded cells 107 +/- 26 nM (n = 13). Treatment of fura-2 loaded cells with 100 microM ouabain saline for 10-60 min progressively elevated the Ca2+i to a mean of 266 +/- 83 nM (n = 15). Reduction of Na+o (96% Li+ replaced) significantly increased Ca2+i to 317 +/- 77 nM (n = 8). After pretreatment with ouabain (100 microM), Na+o replacement (Li+) increased Ca2+i at a significantly faster rate [3.6 nM min-1 (control) cf. 19.8 nM min-1 (ouabain)].

UI	MeSH Term	Description	Entries
D009130	Muscle, Smooth	Unstriated and unstriped muscle, one of the muscles of the internal organs, blood vessels, hair follicles, etc. Contractile elements are elongated, usually spindle-shaped cells with centrally located nuclei. Smooth muscle fibers are bound together into sheets or bundles by reticular fibers and frequently elastic nets are also abundant. (From Stedman, 25th ed)	Muscle, Involuntary,Smooth Muscle,Involuntary Muscle,Involuntary Muscles,Muscles, Involuntary,Muscles, Smooth,Smooth Muscles
D010042	Ouabain	A cardioactive glycoside consisting of rhamnose and ouabagenin, obtained from the seeds of Strophanthus gratus and other plants of the Apocynaceae; used like DIGITALIS. It is commonly used in cell biological studies as an inhibitor of the NA(+)-K(+)-EXCHANGING ATPASE.	Acocantherin,G-Strophanthin,Acolongifloroside K,G Strophanthin
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
D005456	Fluorescent Dyes	Chemicals that emit light after excitation by light. The wave length of the emitted light is usually longer than that of the incident light. Fluorochromes are substances that cause fluorescence in other substances, i.e., dyes used to mark or label other compounds with fluorescent tags.	Flourescent Agent,Fluorescent Dye,Fluorescent Probe,Fluorescent Probes,Fluorochrome,Fluorochromes,Fluorogenic Substrates,Fluorescence Agents,Fluorescent Agents,Fluorogenic Substrate,Agents, Fluorescence,Agents, Fluorescent,Dyes, Fluorescent,Probes, Fluorescent,Substrates, Fluorogenic
D006168	Guinea Pigs	A common name used for the genus Cavia. The most common species is Cavia porcellus which is the domesticated guinea pig used for pets and biomedical research.	Cavia,Cavia porcellus,Guinea Pig,Pig, Guinea,Pigs, Guinea
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
D001572	Benzofurans	Compounds that contain a BENZENE ring fused to a furan ring.	Coumarones,Diphenylbenzofuran
D012964	Sodium	A member of the alkali group of metals. It has the atomic symbol Na, atomic number 11, and atomic weight 23.	Sodium Ion Level,Sodium-23,Ion Level, Sodium,Level, Sodium Ion,Sodium 23
D013050	Spectrometry, Fluorescence	Measurement of the intensity and quality of fluorescence.	Fluorescence Spectrophotometry,Fluorescence Spectroscopy,Spectrofluorometry,Fluorescence Spectrometry,Spectrophotometry, Fluorescence,Spectroscopy, Fluorescence
D016257	Fura-2	A fluorescent calcium chelating agent which is used to study intracellular calcium in tissues.	Fura 2