Biomaterial Database

Differential covalent labeling of apical and basal-lateral membranes of the epithelium of the toad bladder. 1976

E B Ekblad, and J M Strum, and I S Edelman

The apical (luminal) plasma membrane of toad bladder epithelial cells has been labeled with (125I) diazo-diiodo sulfanilic acid (125I-DDISA) as demonstrated by electron-microscopic autoradiography. The silver grains (125I) were localized exclusively to the apical surface. At concentrations of DDISA of 10(-3) M or less, binding to the apical membrane had no significant effect on the fine structure of the epithelium. At concentrations of DDISA of 10(-6) M or less, the baseline short-circuit current (SCC), and the response to cyclic 3',5'-adenosine monophosphate (cAMP) plus theophylline were unimpaired. At 10(-5) M, baseline SCC was unchanged and the response to cyclic AMP plus theophylline was enhanced. At concentrations of 10(-4) M and greater baseline SCC was depressed and the response to the nucleotide inhibited. The basal-lateral epithelial plasma membranes were labeled by exposing the serosal side to pyridoxal phosphate and reducing the resultant Schiff base with sodium borotritide (3H-NaBH1). In electron-microscopic autoradiographs, the silver grains (3H) were found over the basal and lateral surfaces of the epithelium. At concentrations of pyridoxal phosphate of 10(-4) M and 3H-NaBH1 of 10(-3) M, there were no significant changes in the fine structure of the epithelium. Addition of pyridoxal phosphate (10(-4) M) and NaBH4 (10(-3) M) to the serosal side decreased the baseline SCC significantly but not the response to vasopressin. Covalent attachment of the 125I and the 3H was indicated by resistance to elution in the preparation of the sections for electron-microscopy and the reagent requirements for binding.

UI	MeSH Term	Description	Entries
D008854	Microscopy, Electron	Microscopy using an electron beam, instead of light, to visualize the sample, thereby allowing much greater magnification. The interactions of ELECTRONS with specimens are used to provide information about the fine structure of that specimen. In TRANSMISSION ELECTRON MICROSCOPY the reactions of the electrons that are transmitted through the specimen are imaged. In SCANNING ELECTRON MICROSCOPY an electron beam falls at a non-normal angle on the specimen and the image is derived from the reactions occurring above the plane of the specimen.	Electron Microscopy
D011732	Pyridoxal Phosphate	This is the active form of VITAMIN B 6 serving as a coenzyme for synthesis of amino acids, neurotransmitters (serotonin, norepinephrine), sphingolipids, aminolevulinic acid. During transamination of amino acids, pyridoxal phosphate is transiently converted into pyridoxamine phosphate (PYRIDOXAMINE).	Pyridoxal 5-Phosphate,Pyridoxal-P,Phosphate, Pyridoxal,Pyridoxal 5 Phosphate,Pyridoxal P
D001743	Urinary Bladder	A musculomembranous sac along the URINARY TRACT. URINE flows from the KIDNEYS into the bladder via the ureters (URETER), and is held there until URINATION.	Bladder,Bladder Detrusor Muscle,Detrusor Urinae,Bladder Detrusor Muscles,Bladder, Urinary,Detrusor Muscle, Bladder,Detrusor Muscles, Bladder
D001894	Borohydrides	A class of inorganic or organic compounds that contain the borohydride (BH4-) anion.	Borohydride
D002024	Bufo marinus	A species of the true toads, Bufonidae, becoming fairly common in the southern United States and almost pantropical. The secretions from the skin glands of this species are very toxic to animals.	Rhinella marina,Toad, Giant,Toad, Marine,Giant Toad,Giant Toads,Marine Toad,Marine Toads,Toads, Giant,Toads, Marine
D002462	Cell Membrane	The lipid- and protein-containing, selectively permeable membrane that surrounds the cytoplasm in prokaryotic and eukaryotic cells.	Plasma Membrane,Cytoplasmic Membrane,Cell Membranes,Cytoplasmic Membranes,Membrane, Cell,Membrane, Cytoplasmic,Membrane, Plasma,Membranes, Cell,Membranes, Cytoplasmic,Membranes, Plasma,Plasma Membranes
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
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
D001391	Azo Compounds	Organic chemicals where aryl or alkyl groups are joined by two nitrogen atoms through a double bond (R-N	Azo Dye,Azo Dyes,Compounds, Azo,Dye, Azo,Dyes, Azo