Submitted to: Journal of Morphology
Publication Type: Peer reviewed journal
Publication Acceptance Date: 1/26/1999
Publication Date: N/A
Citation: Interpretive Summary: The stable fly and the tsetse fly are very serious biting pests that attack cattle and cause millions of dollars of losses each year; the tsetse fly transmits African sleeping sickness. Both of these insects are very difficult to control using chemical pesticides, and the use of such pesticides can be environmentally harmful. It is important to develop new methods of control that are effective and that do not harm the environment One possible means of controlling biting flies is to exploit the fact that flies (as do other insects), make small amounts of chemicals called neuropeptides that are responsible for regulating essentially all of their life processes (water balance, digestion, etc.). It may be possible to develop chemicals that mimic the actions of neuropeptides and that will successfully kill pest flies while being harmless to other creatures and that will not pollute the environment. In this present study, very careful lwork was done to examine the organ in the bodies of the stable fly and tsetse fly that makes neuropeptides. The work showed that there are significant differences in this organ between these two kinds of flies, and both of these flies differ from the mosquito. The studies were done with a technique called electron microscopy, which allows pictures to be taken at the microscopic level. These studies are important in understanding how neuropeptides are made within the bodies of the stable fly and tsetse fly, and they will provide solid scientific information to help in the ultimate development of methods to manage these insects using neuropeptide-based control technology.
Technical Abstract: Ultrastructural analysis of the corpora cardiaca of the stable fly, Stomoxys calcitrans and the tsetse fly, Glossina morsitans revealed the presence of elementary neurosecretory granules (ENG) unique to the intrinsic neurosecretory cells (INC) of these species. In addition to electron dense spherical ENG, the INC of the corpus cardiacum of the stable efly contain electron dense angular ENG, either square or rectangular in shape; while the INC of the tsetse fly contain only electron dense spindle-shaped ENG. The unique granules of these INC can be traced within nerves to their sites of storage and release, eliminating the need for labeling with artificial probes. Although the INC of the corpus cardiacum of most species have been found to be fuchsinophilic, neither the INC of the stable fly nor the tsetse fly are aldehyde-fuchsinophilic.