Distribution of FMRFamide‐related peptides in the blood‐feeding bug Rhodnius prolixus

Abstract

Immunohistochemistry was used to study the distribution of FMRFamide-like material in the central and peripheral nervous systems and visceral tissues of 5th instar Rhodnius prolixus. Over 200 immunoreactive cell bodies and their processes as well as extensive neuropile regions were distributed throughout the nervous system. Immunoreactive processes were seen over the cephalic aorta, corpus cardiacum/corpus allatum complex, and in neurohaemal sites on the abdominal nerves. In visceral tissues, immunoreactive processes were seen innervating the salivary glands, the foregut, and the hindgut. Immunoreactive cells were also found in the anterior midgut (i.e., the crop and the anterior intestine). A radioimmunoassay specific for "RFamide" carboxy-terminal peptides was used to quantify the amount and the distribution of FMRFamide-like material. Reversed-phase high performance liquid chromatography of nervous tissue extracts revealed several peaks of immunoreactive material. The results suggest the existence of a number of FMRFamide-related peptides in Rhodnius which may have roles in both central and peripheral transmission, may be released as neurohormones and may have endocrine functions in the gut.

An unusual myosuppressin from the blood-feeding bugRhodnius prolixus

“…Immunohistochemistry using an anti-RFamide antibody in R. prolixus reveals immunostained processes projecting to the hindgut (Tsang and Orchard, 1991) and also positively stained endocrinelike cells throughout the entire midgut (this study). These endocrinelike cells appear to be of the open type with processes extending from the cell body towards the lumen.…”

“…FMRFamide-like immunoreactivity is distributed extensively in the neurons of the CNS, in processes associated with the hindgut of R. prolixus, and in processes over the foregut and hindgut (Tsang and Orchard, 1991). Closer examination of the anterior and posterior midgut of 5th instar R. prolixus for FMRFamide-like immunoreactivity revealed FMRFamide-like immunoreactive endocrine-like cells (Fig.4).…”

Identification of the elusive peptidergic diuretic hormone in the blood-feeding bugRhodnius prolixus: a CRF-related peptide

“…In R. prolixus the medial NSCs show immunoreactivity for several neuropeptides, including RF-amidelike (Tsang and Orchard, 1991) and DH 31 -like peptides (Te Brugge et al, 2005). Co-localization of kinin-like and CRF-like immunoreactivity is also observed in R. prolixus in the posterior lateral NSCs of the MTGM (Te Brugge et al, 2001).…”

Dopaminergic and serotonergic innervation of cockroach salivary glands:distribution and morphology of synapses and release sites

“…reported in the salivary glands of the locust and the bloodfeeding bug, Rhodnius prolixus (Myers and Evans, 1985;Tsang and Orchard, 1991;Veelaert et al, 1995;Fusé et al, 1996;Ali, 1997;Te Brugge and Orchard, 2002), our knowledge of the role of neuropeptides in the control of salivation is far from complete. In particular, evidence for the peptidergic innervation of cockroach salivary glands is still lacking and awaits detailed investigation.…”