Printed in U.S.A. FURTHER EVALUATION OF AN INTRA VITAM STAINING I-1ETHOD FOR THE DETECTION OF EARLY IN VIVO

Bousomis, JOHN 0. AND ERNEST BuEDING: Further evaluation of an intra vitam staining method for the detection of early in vito antischistosomal effects. J. Pharmacol. Exp. Ther. 176: 455-463. 1971. One of the earliest effects of a number of structurally unrelated anti-schistosomal drugs is damage to the female reproductive organs. This is demonstrable by the use of an intra ui/am staining method with a tetrazolium salt. The administration of potassium antimony tartrate, niridazole, nicarbazin and p-rosaniline to mice infected with mature Schi,slosonma man.soni resulted in detectable damage to the reproductive organs of female worms within 5 miulutes, 4 to 6 hours, 12 hours and 3 days, respectively. Although tIme effects produced by each of these four drugs were reversed in the five months after treatment, no such reversal was seen after this time interval when the mice were treated with sublethal doses of a nitrofuran derivative. Although these changes can be brought about also by compounds which selectively produce only a reversible functional damage to the female reproductive system of the worm, it is suggested that this procedure could he useful for the rapid detection of compounds which have potential chemotherapeuti