Document Detail


Neuroprotective activities of carvedilol and a hydroxylated derivative: role of membrane biophysical interactions.
MedLine Citation:
PMID:  9973186     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
Carvedilol is a vasodilating beta-blocker and antioxidant approved for treatment of mild to moderate hypertension, angina, and congestive heart failure. SB 211475 (4-[2-hydroxyl-3-[[2-(2-methoxyphenoxy)ethyl]amino]propoxyl]-9H-++ +carbazol-3-ol), a hydroxylated carvedilol analogue, is an even more potent antioxidant in several assay systems. Carvedilol also has neuroprotective capacity with modulatory actions at N-methyl-D-aspartate (NMDA) receptors and Na+ channels. In the present study, we demonstrated that in cultured rat cerebellar neurons, SB 211475 has 28-fold greater antioxidant activity than carvedilol, but is 2- to 6-fold less potent, respectively, at inhibiting neurotoxic activities at Na+ channels and at NMDA receptor channels. To determine a biophysical rationale for these differential activities, small angle x-ray scattering data were obtained from model lipid and brain membrane bilayers containing either carvedilol, SB 211475, or dihydropyridine calcium channel blockers. Electron density profiles revealed that the location of SB 211475 was restricted to the glycerol backbone/hydrocarbon interface and significantly reduced membrane width by 5%, whereas the time-averaged location for carvedilol and flunarizine also extended to the hydrated surface of the bilayer. Comparison of carvedilol with several dihydropyridines showed a correlation between high ClogP values (lipophilicity), Na+ channel inhibitory potency, and bilayer localization. The antioxidant activity of SB 211475 could be explained by restricted intercalation into the glycerol phosphate/hydrocarbon interface, creating an increase in volume associated with the phospholipid acyl chains, which would then become resistant to lipid peroxidation. Differential channel modulation may also be explained by these membrane structural results, which indicate that carvedilol and the less spatially restricted dihydropyridine molecules are more likely to inhibit transmembrane receptor channels.
Authors:
P G Lysko; K A Lysko; C L Webb; G Feuerstein; P E Mason; M F Walter; R P Mason
Related Documents :
6354566 - Update on calcium-channel blocking agents.
8733036 - Effects of antihypertensive therapy on platelet cytosolic calcium responses to low dens...
2156356 - Protease activity in brain, nerve, and muscle of hens given neuropathy-inducing organop...
3544786 - Short- and long-term effects of calcium entry blockers on the kidney.
3770186 - Nicotine-evoked disassembly of cortical actin filaments in adrenal chromaffin cells.
6329336 - Inhibition of bovine spermatozoa by caudal epididymal fluid: i. studies of a sperm moti...
Publication Detail:
Type:  Journal Article    
Journal Detail:
Title:  Biochemical pharmacology     Volume:  56     ISSN:  0006-2952     ISO Abbreviation:  Biochem. Pharmacol.     Publication Date:  1998 Dec 
Date Detail:
Created Date:  1999-02-12     Completed Date:  1999-02-12     Revised Date:  2003-11-14    
Medline Journal Info:
Nlm Unique ID:  0101032     Medline TA:  Biochem Pharmacol     Country:  ENGLAND    
Other Details:
Languages:  eng     Pagination:  1645-56     Citation Subset:  IM    
Affiliation:
Department of Cardiovascular Pharmacology, SmithKline Beecham Pharmaceuticals, King of Prussia, PA, USA. Paul_G_Lysko@sbphrd.com
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Animals
Antioxidants / pharmacology
Calcium Channel Blockers / chemistry
Carbazoles / chemistry,  pharmacology*
Cell Membrane / chemistry,  drug effects*
Cells, Cultured
Cerebellum / chemistry
Dihydropyridines / antagonists & inhibitors
Free Radical Scavengers / pharmacology
Lipid Bilayers / chemistry
Models, Molecular
Neurons / chemistry,  drug effects*
Neuroprotective Agents / pharmacology*
Propanolamines / chemistry,  pharmacology*
Rats
Rats, Sprague-Dawley
Receptors, N-Methyl-D-Aspartate / drug effects
Sodium Channel Blockers
Veratridine / toxicity
X-Ray Diffraction
Chemical
Reg. No./Substance:
0/Antioxidants; 0/Calcium Channel Blockers; 0/Carbazoles; 0/Dihydropyridines; 0/Free Radical Scavengers; 0/Lipid Bilayers; 0/Neuroprotective Agents; 0/Propanolamines; 0/Receptors, N-Methyl-D-Aspartate; 0/Sodium Channel Blockers; 146574-43-8/SB 211475; 71-62-5/Veratridine; 72956-09-3/carvedilol

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  Incorporation of exogenous precursors into neutral lipids and phospholipids in rat hepatocytes: effe...
Next Document:  Methoxyresorufin: an inappropriate substrate for CYP1A2 in the mouse.