P-glycoprotein


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Related to P-glycoprotein: ABCB1

glycoprotein

 [gli″ko-pro´tēn]
any of a class of conjugated proteins consisting of a compound of protein with a carbohydrate group.
α1-acid glycoprotein an acute phase protein found in blood plasma, an indicator of tissue necrosis and inflammation. Called also orosomucoid.
P-glycoprotein a cell-surface protein occurring normally in the colon, small intestine, adrenal glands, kidney, and liver, and also expressed by tumor cells. It is a modulator of multidrug resistance, mediating the transport of antineoplastic agents out of tumor cells.
variable surface glycoprotein any of several glycoproteins that form the antigenic protein coating of Trypanosoma brucei. The organisms contain numerous genes encoding hundreds of such glycoproteins and, by expressing individual ones successively, evade the immune system of the host.

P-gly·co·pro·tein

(glī'kō-prō'tēn),
Protein associated with tumor multidrug resistance; acts as energy-requiring efflux pump for many classes of natural products and chemotherapeutic drugs.
Synonym(s): P-170

P-gly·co·pro·tein

(glī'kō-prō'tēn)
Protein associated with tumor multidrug resistance; acts as an energy-requiring efflux pump for many classes of natural products and chemotherapeutic drugs.

P-glycoprotein

A cell membrane pump that influences cellular uptake and release of chemicals. It affects the relative resistance or susceptibility of cells to drug therapy.
See also: glycoprotein
References in periodicals archive ?
Xiaofeng, "The research of P-glycoprotein expression and drug-resistance reversion in peripheral blood lymphocytes of rheumatoid arthritis," Chinese Journal of Rheumatology, vol.
Pharmacokinetic interaction of cytochrome p450 3A-related compounds with rhodamine 123, a p-glycoprotein substrate, in rats pretreated with dexamethasone.
NIEHS postbaccalaureate fellow David Banks is lead author on the paper and described amitriptylines action on P-glycoprotein as rapid and reversible.
Another important reason for eradication failure was reduced permeability of cell membranes to certain drugs, reduced drug binding to intracellular targets, and the role of P-glycoprotein (5).
Basavappa, "Selective modulation of P-glycoprotein's ATPase and anion efflux regulation activities with PKC a and PKC E in Sf9 cells," Cancer Chemotherapy and Pharmacology, vol.
P-Glycoprotein which is present in tumor cells and which helps cytostatic elimination from the cells uses [sup.99m]Tc-MIBI as the substrate.
Zhou, "Structure, function and regulation of P-glycoprotein and its clinical relevance in drug disposition," Xenobiotica, vol.
Walker, "The role of the ATP-binding cassette transporter P-glycoprotein in the transport of [beta]-amyloid across the blood-brain barrier," Current Pharmaceutical Design, vol.
Liu, "Influence of P-glycoprotein on brucine transport at the in vitro blood-brain barrier," European Journal of Pharmacology, vol.
Predicted properties Epoxy-[alpha]- Epoxy-methoxy- lapachone lapachol Absorption Caco2 permeability 1.595 1.584 Intestinal absorption 100 100 Skin Permeability -3.242 -3.249 P-Glycoprotein substrate Yes Yes P-Glycoprotein inhibitor No No Distribution Volume of distribution 0.201 -0.012 Fraction unbound (human) 0.283 0.392 BBB permeability 0.325 0.260 CNS permeability -2.087 -2.014 Metabolism CYP3A4 substrate Yes No CYP2D6 substrate No No CYP3A4 inhibitor No No CYP2D6 inhibitor No No CYP1A2 inhibitor Yes Yes Excretion Total clearance 0.07 0.197 Toxicity AMES toxicity No Yes Max.
Recommended over-the-counter doses (range = 2-8 mg daily) do not produce opioid effects in the central nervous system because of poor oral bioavailability and P-glycoprotein efflux * of the medication (1); recent reports suggest that large doses (50-300 mg) of loperamide produce euphoria, central nervous system depression, and cardiotoxicity (2-4).
Keywords: Adenosine triphosphate-binding cassette subfamily B member 1 (ABCB1), Polymorphism, post-operative nausea and vomiting, P-glycoprotein (P-gp).