Biomaterial Database

Cholera toxin: radio-iodination and uptake by the intestine of sucking rats. 1993

Aye-Kyaw, and K T Win, and L L Oo, and T Oo

Department of Medical Research, Yangon, Myanmar, Burma.

1. The chloramine-T procedure was employed to radio-iodinate cholera toxin using Na125I. The procedure was found to be efficient and reproducible. 2. Intragastric injections of both the labelled and the unlabelled toxin produced (a) significant increases in intestinal fluid accumulation as measured by the fluid accumulation ratio; (b) significant increases in cAMP levels; and (c) significant decreases in cAMP-phosphodiesterase activities when compared with the controls suggesting that radio-iodination did not impair the biological activity of the toxin. 3. In vivo uptake studies of the labelled toxin by different parts of the intestine indicated that the uptake by the duodenum and jejunum was high and rapid when compared with the ileum implying that there are more binding sites (or receptor proteins) for cholera toxin in the duodenum and jejunum than in the ileum.

UI	MeSH Term	Description	Entries
D007408	Intestinal Absorption	Uptake of substances through the lining of the INTESTINES.	Absorption, Intestinal
D007457	Iodine Radioisotopes	Unstable isotopes of iodine that decay or disintegrate emitting radiation. I atoms with atomic weights 117-139, except I 127, are radioactive iodine isotopes.	Radioisotopes, Iodine
D007553	Isotope Labeling	Techniques for labeling a substance with a stable or radioactive isotope. It is not used for articles involving labeled substances unless the methods of labeling are substantively discussed. Tracers that may be labeled include chemical substances, cells, or microorganisms.	Isotope Labeling, Stable,Isotope-Coded Affinity Tagging,Isotopically-Coded Affinity Tagging,Affinity Tagging, Isotope-Coded,Affinity Tagging, Isotopically-Coded,Isotope Coded Affinity Tagging,Labeling, Isotope,Labeling, Stable Isotope,Stable Isotope Labeling,Tagging, Isotope-Coded Affinity,Tagging, Isotopically-Coded Affinity
D002700	Chloramines	Inorganic derivatives of ammonia by substitution of one or more hydrogen atoms with chlorine atoms or organic compounds with the general formulas R2NCl and RNCl2 (where R is an organic group).	Chloroamines
D002772	Cholera Toxin	An ENTEROTOXIN from VIBRIO CHOLERAE. It consists of two major protomers, the heavy (H) or A subunit and the B protomer which consists of 5 light (L) or B subunits. The catalytic A subunit is proteolytically cleaved into fragments A1 and A2. The A1 fragment is a MONO(ADP-RIBOSE) TRANSFERASE. The B protomer binds cholera toxin to intestinal epithelial cells and facilitates the uptake of the A1 fragment. The A1 catalyzed transfer of ADP-RIBOSE to the alpha subunits of heterotrimeric G PROTEINS activates the production of CYCLIC AMP. Increased levels of cyclic AMP are thought to modulate release of fluid and electrolytes from intestinal crypt cells.	Cholera Toxin A,Cholera Toxin B,Cholera Toxin Protomer A,Cholera Toxin Protomer B,Cholera Toxin Subunit A,Cholera Toxin Subunit B,Choleragen,Choleragenoid,Cholera Enterotoxin CT,Cholera Exotoxin,Cholera Toxin A Subunit,Cholera Toxin B Subunit,Procholeragenoid,Enterotoxin CT, Cholera,Exotoxin, Cholera,Toxin A, Cholera,Toxin B, Cholera,Toxin, Cholera
D003967	Diarrhea	An increased liquidity or decreased consistency of FECES, such as running stool. Fecal consistency is related to the ratio of water-holding capacity of insoluble solids to total water, rather than the amount of water present. Diarrhea is not hyperdefecation or increased fecal weight.	Diarrheas
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
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
D000833	Animals, Suckling	Young, unweaned mammals. Refers to nursing animals whether nourished by their biological mother, foster mother, or bottle fed.	Animal, Suckling,Suckling Animal,Suckling Animals
D014105	Tosyl Compounds	Toluenesulfonyl compounds with general formula CH3C6H4S(O2)R” widely used to block amino groups in the course of syntheses of drugs and other biologically active compounds.	Toluenesulfonyl Compounds,Compounds, Toluenesulfonyl,Compounds, Tosyl