These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.
Pubmed for Handhelds
PUBMED FOR HANDHELDS
Search MEDLINE/PubMed
Title: The actions of FxRFamide related neuropeptides on identified neurones from the snail, Helix aspersa. Author: Pedder SM, Walker RJ. Journal: Acta Biol Hung; 1999; 50(1-3):185-98. PubMed ID: 10574439. Abstract: Intracellular recordings were made from identified neurones in the suboesophageal ganglia of the snail, Helix aspersa. The actions of the eight FxRFamide analogues were investigated on these neurones. These peptides included ones isolated from arthropods and nematodes. All the peptides excited certain neurones while inhibiting others, though their relative potencies varied. Overall on neurones inhibited by these peptides the potency order was: DNFLRFamide > FMRFamide > PDVDHVFLRFamide = KNEFIRFamide > FLRFamide >> SDRNFLRFamide = SDPNFLRFamide > KHEYLRFamide. However, if the responses are compared on individual cell types, then the picture becomes more complex. For example, on cell F-2, KNEFIRFamide proved to be potent with an EC-50 value of 0.54 microM. On neurones F-13/16 and E-16, PDVDHVFLRFamide was inhibitory while FMRFamide, FLRFamide, SDRNFLRFamide and SDPNFLRFamide were excitatory. In terms of overall excitatory actions, the data are less complete but an approximate order of potency is: FMRFamide > DNFLRFamide >> SDPNFLRFamide > PDVDHVFLRFamide >> KNEFIRFamide = KHEYLRFamide = SDRNFLRFamide. However this again varies between specific neurones. These results demonstrate that peptides from insects, crustacea and nematodes are active on Helix neurones and may activate specific receptor subtypes, indicating the possible presence of endogenous analogues of these non-molluscan peptides in the Helix nervous system.[Abstract] [Full Text] [Related] [New Search]