High affinity specific (/sup 3/H)(/sup +/)PN 200-110 binding to dihydropyridine receptors associated with calcium channels in rat cerebral cortex and heart
The binding properties of the 1,4-dihydropyridine calcium channel antagonist, (/sup 3/H)(/sup +/)PN 200-110, were studied in rat cerebral cortical and cardiac homogenates (37/sup 0/C, Krebs phosphate buffer). Specific binding of (/sup 3/H)(/sup +/)PN 200-110 was saturable, reversible, and of high affinity (K/sub d/ values are 35 and 64 pM for the cerebral cortex and heart, respectively). In parallel studies with (/sup 3/H)(/sup +/)PN 200-110, the dissocation constant of (/sup 3/H)nitrendipine was 10-12 times higher. Substituted dihydropyridine calcium channel antagonists and agonists competively inhibited specific (/sup 3/H)(/sup +/)PN 200-110 binding, but d-cis diltiazem enhanced and verapamil incompletely inhibited (/sup 3/H)(/sup +/)PN 200-110 binding in both the cerebral cortex and the heart. The effects of diltiazem and verapamil on
- Research Organization:
- Univ. of Arizona Coll. of Medicine, Tucson
- OSTI ID:
- 6271877
- Journal Information:
- Life Sci.; (United States), Journal Name: Life Sci.; (United States) Vol. 35:7; ISSN LIFSA
- Country of Publication:
- United States
- Language:
- English
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