Characteristic differences in modulation of stomatogastric musculature by a neuropeptide in three species of Cancer crabs.
Stomatogastric musculature from crabs in the genus Cancer provides a system in which modulatory roles of peptides from the FLRFamide family can be compared. The anterior cardiac plexus (ACP) is a neuroendocrine release site within the Cancer stomatogastric nervous system that is structurally identical in C. borealis, C. productus, and C. magister but that appears to contain FLRFamide-like peptide(s) only in C. productus. We measured the effect of TNRNFLRFamide on nerve-evoked contractions of muscles that were nearby, an intermediate distance, or far from the ACP. We found the spatial pattern of FLRFamidergic modulation of muscles in C. productus to be qualitatively different than in C. borealis or C. magister. In C. productus, muscles proximal to the ACP were more responsive than distal muscles. In C. borealis, FLRFamidergic response was less dependent on muscle location. These results suggest that functionally different roles of FLRFamides in modulating stomatogastric muscle movements may have evolved in different Cancer species.
Verley
Derek R
DR
Department of Physics, Santa Clara University, Santa Clara, CA 95053, USA.
Doan
Vu
V
Trieu
Quoc
Q
Messinger
Daniel I
DI
Birmingham
John T
JT
D000818:Animals; D003386:Brachyura / Q000033:anatomy & histology / Q000502:physiology; D004068:Digestive System Physiological Phenomena / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D041981:Gastrointestinal Tract / Q000166:cytology*; D007447:Invertebrate Hormones / Q000494:pharmacology*; D008958:Models, Molecular; D009119:Muscle Contraction / Q000187:drug effects; D009132:Muscles / Q000187:drug effects / Q000294:innervation*; D009469:Neuromuscular Junction / Q000187:drug effects / Q000502:physiology; D009479:Neuropeptides / Q000737:chemistry / Q000494:pharmacology*; D013045:Species Specificity
D007447:Invertebrate Hormones; D009479:Neuropeptides; C070157:TNRNFLRFamide