Studies on the cardiac physiology of Onychophora and Chilopoda.
Cardiac physiology in Onychophora and Chilopoda has not yet been studied by electrophysiological methods. Here we present ECGs and the first intracellular recordings from dorsal vessel muscle cells in Scolopendra cingulata, Lithobius forficatus and Peripatopsis sp. In Onychophora, a myogenic automatism generates the heart function. In the Chilopoda examined, heartbeat is triggered by a neurogenic automatism that is superimposed over a basic myogenic rhythm, which occurs under experimental conditions. The neuropeptide proctolin and the head peptide have no significant effects in the species investigated. The results are discussed from the viewpoints of comparative physiology and phylogenetics.
Hertel
W
W
Institut für Allgemeine Zoologie und Tierphysiologie, Friedrich-Schiller-Universität Jena, D-07743, Jena, Germany. christian.wirkner@web.de
Wirkner
C S
CS
Pass
G
G
D000200:Action Potentials / Q000187:drug effects / Q000502:physiology; D000779:Anesthetics, Local / Q000494:pharmacology; D000818:Animals; D001181:Arthropods / Q000502:physiology*; D001683:Biological Clocks / Q000502:physiology; D004562:Electrocardiography; D004594:Electrophysiology; D006321:Heart / Q000294:innervation / Q000502:physiology*; D009200:Myocardial Contraction / Q000187:drug effects / Q000502:physiology; D009420:Nervous System / Q000187:drug effects; D009479:Neuropeptides; D018377:Neurotransmitter Agents / Q000494:pharmacology; D009842:Oligopeptides / Q000494:pharmacology; D013779:Tetrodotoxin / Q000494:pharmacology
D000779:Anesthetics, Local; D009479:Neuropeptides; D018377:Neurotransmitter Agents; D009842:Oligopeptides; D013779:Tetrodotoxin; C011536:proctolin