Characteristics of [125I]omega-conotoxin MVIIA binding to rat neocortical membranes

• Published in: Neuroscience letters Vol. 161; no. 1; p. 113
• Main Authors: Stoehr, S J, Dooley, D J
• Format: Journal Article
• Language: English
• Published: Ireland 14-10-1993
• Subjects: Amino Acid Sequence; Animals; Calcium Channel Blockers - pharmacology; Calcium Channels - metabolism; Cerebral Cortex - metabolism; Humans; Male; Membranes - metabolism; Molecular Sequence Data; Neomycin - pharmacology; Neurons - metabolism; omega-Conotoxin GVIA; omega-Conotoxins; Peptides - antagonists & inhibitors; Peptides - genetics; Peptides - metabolism; Rats; Rats, Sprague-Dawley; Spermine - pharmacology
• ISSN: 0304-3940
• DOI: 10.1016/0304-3940(93)90153-C

[125I]omega-Conotoxin MVIIA (omega-CTM) binding to N-type voltage-sensitive calcium channels (VSCCs) was characterized using rat neocortical membranes. [125I]omega-CTM bound rapidly and with high affinity; these parameters were similar to binding using omega-conotoxin GVIA ([125I]omega-CTG). Unlike [125I]omega-CTG, however, [125I]omega-CTM readily dissociated from its binding site. Monovalent and divalent cations, polyamines, and aminoglycosides inhibited [125I]omega-CTM binding. Since [125I]omega-CTM appears to bind to the same site as [125I]omega-CTG in mammalian neurons, the reversibility of [125I]omega-CTM binding makes this ligand preferable for equilibrium binding analyses.