Scanning electron microscopy of the dorsal vessel of Panstrongylus megistus (Burmeister, 1835) (Hemiptera: Reduviidae)

Abstract

In this study we analyzed the microanatomy of the dorsal vessel of the triatomine Panstrongylus megistus. The organ is a tubule anatomically divided into an anterior aorta and a posterior heart, connected to the body wall through 8 pairs of alary muscles. The heart is divided in 3 chambers by means of 2 pairs of cardiac valves. A pair of ostia can be observed in the lateral wall of each chamber. A bundle of nerve fibers was found outside the organ, running dorsally along its major axis. A group of longitudinal muscular fibers was found in the ventral portion of the vessel. The vessel was found to be lined both internally and externally by pericardial cells covered by a thin laminar membrane. Inside the vessel the pericardial cells were disposed in layers and on the outside they formed clusters or rows.

Drosophila pericardial nephrocyte ultrastructure changes during ageing

“…This work focuses on the ultrastructural analysis of PCNs in D. melanogaster at different develop mental stages. We complete and extend previous ultrastructural studies on pericardial nephrocytes, which mainly concentrated on cells at late larval stages (Brockhouse et al, 1999;Crossley, 1972;Crossley, 1985;Fife et al, 1987;Tepass and Hartenstein, 1994) or on pericardial cells of adult insects from various taxa (Bowers, 1964;Chagas and Caetano, 2003;Crossley, 1972;Mills and King, 1965;Nogueira et al, 1995;Poiani and da Cruz-Landim, 2007;Sanger and McCann, 1968). Less attention has been paid to the ultrastructure of embryonic PCNs.…”