Biomaterial Database

Effect of okadaic acid on human basophil secretion. 1993

L M Botana, and D W MacGlashan

Johns Hopkins Asthma and Allergy Center, Baltimore, MD 21224.

We examined the effects of a phosphatase inhibitor, okadaic acid, on mediator secretion from human basophils. These cells are known to respond to a number of stimuli that appear to utilize distinct biochemical pathways converging on mediator release. Okadaic acid was found to inhibit IgE-mediated release (histamine release inhibited 80 +/- 12% and leukotriene release inhibited 100% following a 10-min preincubation with okadaic acid and stimulation with an optimal concentration of anti-IgE antibody) at a concentration of 1 microM. The concentration-response curve to okadaic acid was steep, with 0.1 microM yielding only 20 +/- 10% inhibition of either mediator. Secretion following stimulation with the univalent stimulus, fMet-Leu-Phe peptide, was not inhibited by okadaic acid. Unlike cAMP-active agents that inhibit cytosolic Ca2+ elevations following IgE-mediated stimulation, the increased state of cellular protein phosphorylation, which presumably results from treatment with 1 microM okadaic acid, had no effect on the elevations in free cytosolic Ca2+ that follow stimulation with anti-IgE antibody of fMet peptide.

UI	MeSH Term	Description	Entries
D007073	Immunoglobulin E	An immunoglobulin associated with MAST CELLS. Overexpression has been associated with allergic hypersensitivity (HYPERSENSITIVITY, IMMEDIATE).	IgE
D009239	N-Formylmethionine	Effective in the initiation of protein synthesis. The initiating methionine residue enters the ribosome as N-formylmethionyl tRNA. This process occurs in Escherichia coli and other bacteria as well as in the mitochondria of eucaryotic cells.	N Formylmethionine,Formylmethionine, N
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
D004988	Ethers, Cyclic	Compounds of the general formula R-O-R arranged in a ring or crown formation.	Cyclic Ether,Cyclic Ethers,Ether, Cyclic
D006632	Histamine	An amine derived by enzymatic decarboxylation of HISTIDINE. It is a powerful stimulant of gastric secretion, a constrictor of bronchial smooth muscle, a vasodilator, and also a centrally acting neurotransmitter.	Ceplene,Histamine Dihydrochloride,Histamine Hydrochloride,Peremin
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D001491	Basophils	Granular leukocytes characterized by a relatively pale-staining, lobate nucleus and cytoplasm containing coarse dark-staining granules of variable size and stainable by basic dyes.	Basophil
D015289	Leukotrienes	A family of biologically active compounds derived from arachidonic acid by oxidative metabolism through the 5-lipoxygenase pathway. They participate in host defense reactions and pathophysiological conditions such as immediate hypersensitivity and inflammation. They have potent actions on many essential organs and systems, including the cardiovascular, pulmonary, and central nervous system as well as the gastrointestinal tract and the immune system.	Leukotriene
D015398	Signal Transduction	The intracellular transfer of information (biological activation/inhibition) through a signal pathway. In each signal transduction system, an activation/inhibition signal from a biologically active molecule (hormone, neurotransmitter) is mediated via the coupling of a receptor/enzyme to a second messenger system or to an ion channel. Signal transduction plays an important role in activating cellular functions, cell differentiation, and cell proliferation. Examples of signal transduction systems are the GAMMA-AMINOBUTYRIC ACID-postsynaptic receptor-calcium ion channel system, the receptor-mediated T-cell activation pathway, and the receptor-mediated activation of phospholipases. Those coupled to membrane depolarization or intracellular release of calcium include the receptor-mediated activation of cytotoxic functions in granulocytes and the synaptic potentiation of protein kinase activation. Some signal transduction pathways may be part of larger signal transduction pathways; for example, protein kinase activation is part of the platelet activation signal pathway.	Cell Signaling,Receptor-Mediated Signal Transduction,Signal Pathways,Receptor Mediated Signal Transduction,Signal Transduction Pathways,Signal Transduction Systems,Pathway, Signal,Pathway, Signal Transduction,Pathways, Signal,Pathways, Signal Transduction,Receptor-Mediated Signal Transductions,Signal Pathway,Signal Transduction Pathway,Signal Transduction System,Signal Transduction, Receptor-Mediated,Signal Transductions,Signal Transductions, Receptor-Mediated,System, Signal Transduction,Systems, Signal Transduction,Transduction, Signal,Transductions, Signal
D019319	Okadaic Acid	A specific inhibitor of phosphoserine/threonine protein phosphatase 1 and 2a. It is also a potent tumor promoter. It is produced by DINOFLAGELLATES and causes diarrhetic SHELLFISH POISONING.	Ocadaic Acid