EN
The corazonin (Crz), was originally purifi ed as a cardioacceleratory neuropeptide in P. americana. Following studies indicated that Crz induces dark colorization and morphometric changes in locust; reduces the spanning rate of silk in B. mori; is implicated in circadian clock. The pigment dispersing hormone/pigment dispersing factor (PDH/PDF), primary was described in crustaceans and in following studies in insects. Researchers have shown its role in circadian organization of insects as a important output factor of circadian clock. CCAP (crustacean cardioactive peptide), has a broad range of activity including: cardioacceleratory effect; affecting muscle and gut functions; induces release of AKH. Mapping of Crz-, PDF-, CCAP- containing neurons provides an important information concerning sites of release and action of these peptides. Here we employed immunohistochemical methods to confi rm the presence of above mentioned neuropeptides and to investigate their distribution in the brain of Spodoptera exigua (Lepidoptera) and Pyrrhocoris apterus (Hemiptera). Using [His7]-Crz antibody we were able to detect immunoreactive signal in both species in dorsolateral (DL) neurosecretory cells projecting ipsilateraly to the corpora cardiaca. Additional immunoreative somata were observed in pars intercerebralis (PIC). PDF-like immunoreativity was observed in optic lobes, DL and much weaker in PIC. CCAP-ir was detected in OL and PIC.