Abstract
1. 1. The binding characteristics ( B max and K d ) of the α-adrenoceptor radioligand [ 3H] WB4101 in crude membrane fraction (fraction P 2) from cerebral cortex were studied after 13-day oral treatment of male Wistar rats with the Ca 2+-antagonists nifedipine (20 mg/kg), verapamil (50 mg/kg), flunarizine (10 mg/kg) and with the calmodulin-antagonist trifluoperazine (TFP) (3 mg/kg). 2. 2. A significant reduction of the binding sites ( B max) for [ 3H] WB4101 was established after the three Ca 2+-antagonists as well as after TFP treatment. 3. 3. Different changes in the affinity constant ( K d ) of brain adrenoceptors were observed depending on the type of the Ca 2+ or CaM- antagonist used: nifedipine did not change the K d value, verapamil and TFP decreased whereas flunarizine increased the K d value. 4. 4. Relationships between Ca ions and α-adrenoceptor functions are suggested.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
