Biomaterial Database

Control of cultured epithelial (MDCK) cell transport function: identification of a beta-adrenoceptor coupled to adenylate cyclase. 1984

E L Rugg, and N L Simmons

A catecholamine-sensitive adenylate cyclase activity was observed in cell homogenates of cultured renal epithelial (MDCK) cells. 10 microM isoprenaline gave a 2.85-fold increase in adenylate cyclase activity above basal levels. A series of adrenoceptor agonists gave a relative potency series of isoprenaline greater than adrenaline greater than noradrenaline (K1(9) values of 1.9 X 10(-7), 1.6 X 10(-6) and 1.9 X 10(-5) M respectively), consistent with activation of a beta-adrenoceptor. Intracellular accumulation of cyclic AMP was also stimulated by 10 microM isoprenaline, peak values being observed after 2 min, followed by a decline to lower maintained levels. The phosphodiesterase inhibitor isobutylmethylzanthine (1 mM) augmented isoprenaline-stimulated cyclic AMP accumulation. In epithelial preparations of MDCK cells grown upon Millipore filters and mounted in Ussing chambers isoprenaline was only effective in elevating intracellular cyclic AMP contents when applied to the basal cell surfaces. Direct measurement of beta-adrenoceptor density and subtype was determined by (+/-)-3-[125I]iodocyanopindolol binding to MDCK cell homogenates. Binding consisted of a saturable component (Vmax = 14.9 fmol/mg cell protein) of high molar affinity (Kd = 10.8 pM) and a non-saturable component which showed a linear dependence on iodocyanopindolol concentration. In addition to the high-affinity binding site, dissociation kinetics revealed a low-affinity component (Kd = 450 pM) comprising 24% of saturable binding. Competition of (+/-)-3-[125I]iodocyanopindolol binding with beta-adrenoceptor agonists and antagonists was entirely consistent with the existence of a beta 2-adrenoceptor. Examination of various MDCK cultures and clones revealed the existence of MDCK cultures whose adenylate cyclase activity was unresponsive to catecholamine stimulation; this correlated with a reduced or undetectable level of (+/-)-3-[125I]iodocyanopindolol binding. The control of transepithelial chloride transport in MDCK epithelia by catecholamines is discussed.

UI	MeSH Term	Description	Entries
D007668	Kidney	Body organ that filters blood for the secretion of URINE and that regulates ion concentrations.	Kidneys
D010641	Phenotype	The outward appearance of the individual. It is the product of interactions between genes, and between the GENOTYPE and the environment.	Phenotypes
D010869	Pindolol	A moderately lipophilic beta blocker (ADRENERGIC BETA-ANTAGONISTS). It is non-cardioselective and has intrinsic sympathomimetic actions, but little membrane-stabilizing activity. (From Martindale, The Extra Pharmocopoeia, 30th ed, p638)	Prindolol,LB-46,Visken,LB 46,LB46
D011943	Receptors, Adrenergic, beta	One of two major pharmacologically defined classes of adrenergic receptors. The beta adrenergic receptors play an important role in regulating CARDIAC MUSCLE contraction, SMOOTH MUSCLE relaxation, and GLYCOGENOLYSIS.	Adrenergic beta-Receptor,Adrenergic beta-Receptors,Receptors, beta-Adrenergic,beta Adrenergic Receptor,beta-Adrenergic Receptor,beta-Adrenergic Receptors,Receptor, Adrenergic, beta,Adrenergic Receptor, beta,Adrenergic beta Receptor,Adrenergic beta Receptors,Receptor, beta Adrenergic,Receptor, beta-Adrenergic,Receptors, beta Adrenergic,beta Adrenergic Receptors,beta-Receptor, Adrenergic,beta-Receptors, Adrenergic
D002395	Catecholamines	A general class of ortho-dihydroxyphenylalkylamines derived from TYROSINE.	Catecholamine,Sympathin,Sympathins
D002460	Cell Line	Established cell cultures that have the potential to propagate indefinitely.	Cell Lines,Line, Cell,Lines, Cell
D004847	Epithelial Cells	Cells that line the inner and outer surfaces of the body by forming cellular layers (EPITHELIUM) or masses. Epithelial cells lining the SKIN; the MOUTH; the NOSE; and the ANAL CANAL derive from ectoderm; those lining the RESPIRATORY SYSTEM and the DIGESTIVE SYSTEM derive from endoderm; others (CARDIOVASCULAR SYSTEM and LYMPHATIC SYSTEM) derive from mesoderm. Epithelial cells can be classified mainly by cell shape and function into squamous, glandular and transitional epithelial cells.	Adenomatous Epithelial Cells,Columnar Glandular Epithelial Cells,Cuboidal Glandular Epithelial Cells,Glandular Epithelial Cells,Squamous Cells,Squamous Epithelial Cells,Transitional Epithelial Cells,Adenomatous Epithelial Cell,Cell, Adenomatous Epithelial,Cell, Epithelial,Cell, Glandular Epithelial,Cell, Squamous,Cell, Squamous Epithelial,Cell, Transitional Epithelial,Cells, Adenomatous Epithelial,Cells, Epithelial,Cells, Glandular Epithelial,Cells, Squamous,Cells, Squamous Epithelial,Cells, Transitional Epithelial,Epithelial Cell,Epithelial Cell, Adenomatous,Epithelial Cell, Glandular,Epithelial Cell, Squamous,Epithelial Cell, Transitional,Epithelial Cells, Adenomatous,Epithelial Cells, Glandular,Epithelial Cells, Squamous,Epithelial Cells, Transitional,Glandular Epithelial Cell,Squamous Cell,Squamous Epithelial Cell,Transitional Epithelial Cell
D004848	Epithelium	The layers of EPITHELIAL CELLS which cover the inner and outer surfaces of the cutaneous, mucus, and serous tissues and glands of the body.	Mesothelium,Epithelial Tissue,Mesothelial Tissue,Epithelial Tissues,Mesothelial Tissues,Tissue, Epithelial,Tissue, Mesothelial,Tissues, Epithelial,Tissues, Mesothelial
D000242	Cyclic AMP	An adenine nucleotide containing one phosphate group which is esterified to both the 3'- and 5'-positions of the sugar moiety. It is a second messenger and a key intracellular regulator, functioning as a mediator of activity for a number of hormones, including epinephrine, glucagon, and ACTH.	Adenosine Cyclic 3',5'-Monophosphate,Adenosine Cyclic 3,5 Monophosphate,Adenosine Cyclic Monophosphate,Adenosine Cyclic-3',5'-Monophosphate,Cyclic AMP, (R)-Isomer,Cyclic AMP, Disodium Salt,Cyclic AMP, Monoammonium Salt,Cyclic AMP, Monopotassium Salt,Cyclic AMP, Monosodium Salt,Cyclic AMP, Sodium Salt,3',5'-Monophosphate, Adenosine Cyclic,AMP, Cyclic,Adenosine Cyclic 3',5' Monophosphate,Cyclic 3',5'-Monophosphate, Adenosine,Cyclic Monophosphate, Adenosine,Cyclic-3',5'-Monophosphate, Adenosine,Monophosphate, Adenosine Cyclic
D000262	Adenylyl Cyclases	Enzymes of the lyase class that catalyze the formation of CYCLIC AMP and pyrophosphate from ATP.	Adenyl Cyclase,Adenylate Cyclase,3',5'-cyclic AMP Synthetase,Adenylyl Cyclase,3',5' cyclic AMP Synthetase,AMP Synthetase, 3',5'-cyclic,Cyclase, Adenyl,Cyclase, Adenylate,Cyclase, Adenylyl,Cyclases, Adenylyl,Synthetase, 3',5'-cyclic AMP