“Treatment … with idazoxan reduced MTT conversion by 50% at 100microM … by 98% at 1000microM. Phentolamine and quinine reduced viability comparably at 1000microM, but were less toxic at 100microM. On the other hand, the … alinidine and the sulfonylurea tolbutamide were only moderately toxic (less than 40% viability loss at 1000microM).”