1. K+-induced and Ca2+-induced contractures of rat prostatic and epididymal vas deferens smooth muscle were used to screen ABA and its analogue SD217595 for Ca2+ modulatory activity.
2. The Ca2+ agonist BAY K8644 significantry enhanced Ca2+-induced contractures while the Ca2+ entry blocker nifedipine strongly inhibited such contractures in both types of vas deferens preparation over the whole Ca2+ concentration range employed.
3. At 10(-7) mol l(-1) ABA had no significant effect on K+-induced or Ca2+-induced contractures nor did it change the phasic/tonic force ratio in the preparations.
4. The ABA analogue SD217595 strongly inhibited Ca2+-induced contractures over the whole Ca2+ concentration range employed in both prostatic and epididymal vas deferens.
5. It is concluded that ABA is without significant Ca2+ modulatory activity in this smooth muscle preparation but the ABA analogue SD217595 possesses strong Ca2+ entry blocking ability.
|Number of pages||6|
|Publication status||Published - May 1994|