Relaxant effects of some benzothiazolinone derivatives on isolated rabbit corpus cavernosum

In the present study, two 6-(fluorobenzoyl)-3-piperazinomethyl-2benzothiazo line ne derivatives were synthesized and their relaxant effects on isolated rabbit corpus cavernosum investigated. Compounds Y-16 and Y-21 can alter t he ability of corpus cavernosum smooth muscle to contract. Strips of rabbit corpus cavernosum smooth muscle were mounted in isolated tissue baths for measurement of isometric contractile force. Compounds (10(-6)-10(-3) M) did not cause contraction but induced relaxation in precontracted corpus caver nosum smooth muscle. Neither N-nitro-L-arginine methylester (L-NAME) nor in domethacin affected the relaxant effect of these compounds. Glibenclamide a nd tetraethylammonium chloride (TEA) also did not influence the relaxation induced by the compounds. In conclusion, in isolated rabbit corpus cavenosu m, Y16 and Y21 have a relaxant potency equal or superior to known vasoactiv e agents. Further investigations are needed to show the importance of these effects for the diagnosis and treatment of erectile dysfunction.