Leucomyosuppressin, a novel insect neuropeptide, inhibits evoked transmitter release at the mealworm neuromuscular junction.
The action of leucomyosuppressin (LMS: pGlu-Asp-Val-Asp-His-Val-Phe-Leu-Arg-Phe-NH2) on the glutamate-mediated neuromuscular transmission in the mealworm, Tenebrio molitor, was studied by the microelectrode current-clamp and voltage-clamp techniques. Submicromolar concentrations of LMS reversibly attenuate evoked release of transmitter from the motor nerve terminals, as evidenced by a decrease in the quantum content estimated by the number of failures of extracellular EPSPs. LMS has no effect on the glutamate-induced depolarization. Possible intracellular mediators for the LMS action are discussed.
Yamamoto
D
D
Laboratory of Neurophysiology, Mitsubishi-Kasei Institute of Life Sciences, Tokyo, Japan.
Ishikawa
S
S
Holman
G M
GM
Nachman
R J
RJ
D000200:Action Potentials / Q000187:drug effects; D000818:Animals; D004558:Electric Stimulation; D009469:Neuromuscular Junction / Q000187:drug effects / Q000378:metabolism*; D009479:Neuropeptides / Q000494:pharmacology*; D009435:Synaptic Transmission / Q000187:drug effects*; D013712:Tenebrio / Q000187:drug effects / Q000378:metabolism* / Q000502:physiology
D009479:Neuropeptides; C058650:leucomyosuppressin