title: Crustacean cardioactive peptide in the Chagas' disease vector, Rhodnius prolixus: presence, distribution and physiological effects.
abstract: Crustacean cardioactive peptide (CCAP), a cyclic nonapeptide (PFCNAFTGCamide), has multifunctional roles in insects including stimulating visceral and cardiac muscle contraction, and regulating ecdysis. Previously, we have sequenced the cDNA for CCAP from Rhodnius prolixus central nervous system (CNS) and shown expression of the CCAP transcript in neurons of the CNS. In the present study, we have biochemically identified and sequenced CCAP from 5th instar R. prolixus CNS using matrix-assisted laser desorption ionization-time of flight-tandem mass spectrometry, and mapped CCAP-like immunoreactivity in the CNS and peripheral tissues of 5th instar R. prolixus. Physiologically, the hindgut of R. prolixus was found to be sensitive to CCAP, showing dose-dependent increases in contractions with threshold at 5 × 10(-9) M and maximum response at 10(-7) M CCAP. Also, CCAP was found to increase the frequency of the heartbeat in a reversible, dose-dependent manner, with threshold close to 10(-11) M and maximum response at 10(-10) M CCAP.
authors.affiliation: Department of Biology, University of Toronto Mississauga, 3359 Mississauga Road North, Mississauga, Ontario, Canada L5L 1C6. dohee.lee@utoronto.ca
authors.forename: Do Hee
authors.initials: DH
authors.lastname: Lee
authors.forename: Angela B
authors.initials: AB
authors.lastname: Lange
mesh_terms: D000818:Animals; D002490:Central Nervous System / Q000378:metabolism; D014355:Chagas Disease / Q000635:transmission*; D004199:Disease Vectors; D041981:Gastrointestinal Tract / Q000187:drug effects / Q000378:metabolism; D006321:Heart / Q000187:drug effects; D007150:Immunohistochemistry; D009474:Neurons / Q000378:metabolism; D009479:Neuropeptides / Q000378:metabolism* / Q000494:pharmacology; D012239:Rhodnius / Q000378:metabolism*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
chemical_list: D009479:Neuropeptides; C058620:crustacean cardioactive peptide