| Autor: |
Paulussen JJ; Department of Medicinal Chemistry, Utrecht Institute for Pharmaceutical Sciences, Faculty of Pharmacy, Utrecht University, The Netherlands., Fischer MJ, Zuidam NJ, v Miltenburg JC, de Mol NJ, Janssen LH |
| Jazyk: |
angličtina |
| Zdroj: |
Biochemical pharmacology [Biochem Pharmacol] 1999 Mar 01; Vol. 57 (5), pp. 503-10. |
| DOI: |
10.1016/s0006-2952(98)00317-7 |
| Abstrakt: |
Oxatomide is an H1 antihistaminic drug that also inhibits mediator release from mast cells. From previous studies, it appeared that inhibition of the influx of extracellular calcium is the major cause of this inhibition of exocytosis. Here, we explored the role of drug-membrane interactions in the inhibition of mediator release. We investigated the effects on phase transition and fluidity of artificial membranes. All compounds studied distorted the phase transition in L-alpha-dipalmitoylphosphatidylcholine liposomes, which correlated with the drug-induced increase in membrane fluidity measured by fluorescence anisotropy of the bilayer interacting probe 1-[4-(trimethylamino)-phenyl]-6-phenylhexa-1,3,5-triene. Erythrocytes were used to study membrane effects on a cellular level. The hypotonic-induced haemolysis of erythrocytes was inhibited by the drugs. Compounds which increased membrane fluidity of liposomes to a greater extent were also more active in decreasing haemolysis. Drug-induced disturbance of the membranes is related to their effect on the activity of store-operated Ca2+ channels. The activity of these channels in rat basophilic leukemia cells, assayed as 45Ca2+ influx, was most effectively inhibited by oxatomide derivatives, thereby inducing a more rigid membrane structure. Small changes in molecular structure affect the activity of the drugs and these structure-activity relations are discussed. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
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