The influence ofBlastocrithidia triatomae(Trypanosomatidae) on the reduviid bugTriatoma infestans: in vivoandin vitrodiuresis and production of diuretic hormone

Abstract

SUMMARYThe homoxenous flagellateBlastocrithidia triatomaedisturbs excretion inTriatoma infestans. During the first 4 and 24 h after feeding, infected 5th instars excreted approximately a 2·5-fold smaller volume of urine. Consequently, about double the normal volume of haemolymph could be obtained from these infected bugs 24 h after feeding. Surprisingly, thein vitrosecretion rates of Malpighian tubules from uninfected and infected bugs were nearly identical. In addition, the storage and release of diuretic hormone in infected bugs was sufficient to induce normal secretion rates by isolated Malpighian tubules. Therefore, the previously observed ultrastructural alterations in the upper Malpighian tubules of infected bugs do not result in a disturbedin vitrosecretion, althoughin vivoexcretion is reduced.