[Vertebrate hormones influence on the reproduction of Biomphalaria glabrata and on Schistosoma mansoni infection (author's transl)].

The influence of fifteen vertebrate hormones on the B. glabrata reproduction and on S. mansoni infection have been studied. Hecogenine and pregnadienolone significantly increased the snail's number of eggs; testosterone, diethylstilbestrol and estradiol valerianate decreased their number of eggs and the mesterolone and progesterone produced a slight decrease in the number of eggs. Crude hecogenine, pregnenolone, prednisone, estradiol, cholic acid, diosgenin, estrone and pregnadione have not shown any significant alteration on the snail reproduction. None of these hormones presented any influence upon the S. mansoni cycle in B. glabrata. Molluscicidal, oocidal and cercarcidal activities have been observed with diethylstilbestrol in concentrations below 10 ppm.