Effect of serotonin and opiate peptides on ion-currents of dialysed Helix neurons.
The effect of serotonin, Met- and Leu-enkephalin was studied on the dialysed neurons of Helix pomatia L. Both the Ca- and K-currents were modulated by the above agents. Two types of neurons could be distinguished by their response to serotonin in the case of the voltage activated Ca-current. One group responded by increasing the inward Ca-current, others by decreasing it. Met-enkephalin decreased the Ca-current on every studied neuron, while Leu-enkephalin had modulatory action to both directions. Opiate peptides and serotonin showed a dose-dependent effect, but had different threshold concentrations. The peptides and serotonin also influenced the voltage activated transient and delayed K-currents. Serotonin increased the K-current, while Met-enkephalin decreased it, and Leu-enkephalin could either decrease or increase it. The variations on the response to serotonin and the opiate peptides on non-identified dialysed neurons of Helix can be explained by the presence of different receptors on the neurons used.
Valasek
Z
Z
Balaton Limnological Research Institute, Academy of Sciences, Tihany, Hungary.
Rózsa
K S
KS
Fedulova
S A
SA
D000818:Animals; D002118:Calcium / Q000378:metabolism; D004743:Enkephalin, Leucine / Q000494:pharmacology; D004744:Enkephalin, Methionine / Q000494:pharmacology; D006372:Helix, Snails / Q000378:metabolism*; D017136:Ion Transport / Q000187:drug effects; D009474:Neurons / Q000187:drug effects / Q000378:metabolism*; D011188:Potassium / Q000378:metabolism; D012701:Serotonin / Q000494:pharmacology
D012701:Serotonin; D004744:Enkephalin, Methionine; D004743:Enkephalin, Leucine; D011188:Potassium; D002118:Calcium