title: Inhibition and structural changes of liver alkaline phosphatase by tramadol.
abstract: Tramadol is a potent analgesic drug which interacts with mu-opioid and has low effect on other opioid receptors. Unlike other opioids, it has no clinically significant effect on respiratory or cardiovascular parameters. Alakaline phosphatase is a hydrolase enzyme that prefers alkaline condition and removes phosphate group from different substrates. In this study, the interaction between tramadol and calf liver alkaline phosphatase was investigated. The results showed that tramadol can bind to alakaline phosphatase and inhibit the enzyme in an un-competitive manner. Ki and IC50 values of tramadol were determined as about 91 and 92 μM, respectively. After enzyme purification, structural changes on alakaline phosphatase-drug interaction were studied by circular dichroism and fluorescence measurement. These data revealed the alteration in the content of secondary structures and also conformational changes in enzyme occurred when the drug bound to enzyme-substrate complex.
authors.forename: Dariush
authors.initials: D
authors.lastname: Minai-Tehrani
authors.forename: Mahya
authors.initials: M
authors.lastname: Eslami
authors.forename: Nafsa
authors.initials: N
authors.lastname: Khazaei
authors.forename: Elmira
authors.initials: E
authors.lastname: Katebian
authors.forename: Leila
authors.initials: L
authors.lastname: Azizi
authors.forename: Fatemeh
authors.initials: F
authors.lastname: Yazdi
authors.forename: Akram Sadat
authors.initials: AS
authors.lastname: Hosseini
authors.affiliation: BioResearch Lab, Faculty of Biological Sciences, Shahid Beheshti University,G.C. Iran. d_mtehrani@sbu.ac.ir.
authors.forename: Mohammadreza
authors.initials: M
authors.lastname: Taheri
mesh_terms: D000469:Alkaline Phosphatase / Q000037:antagonists & inhibitors* / Q000737:chemistry / Q000378:metabolism; D000701:Analgesics, Opioid / Q000008:administration & dosage / Q000378:metabolism / Q000494:pharmacology*; D000818:Animals; D002417:Cattle; D002942:Circular Dichroism; D020128:Inhibitory Concentration 50; D008099:Liver / Q000201:enzymology*; D011485:Protein Binding; D011487:Protein Conformation; D013050:Spectrometry, Fluorescence; D014147:Tramadol / Q000008:administration & dosage / Q000378:metabolism / Q000494:pharmacology*
chemical_list: D000701:Analgesics, Opioid; D014147:Tramadol; D000469:Alkaline Phosphatase