Endothelin-1 and endothelin-3 modulate dopaminergic neurons through different mechanisms.
Novel vasoconstrictor peptides, endothelin-1 (ET-1) and endothelin-3 (ET-3), are also known as neuropeptides or neuromodulators. When either ET-1 or ET-3 was administered to the rat striatum via a microinjection needle, the dopamine release from the striatum dose-dependently increased. Pretreatment with a glutamate receptor blocker, glutamate diethyl ester hydrochloride, inhibited the dopamine release induced by ET-3, whereas it further enhanced the dopamine release by ET-1. This suggests that ET-1 directly induces the dopamine release, whereas the action of ET-3 is mediated by glutamate receptors. We postulate that this difference may result from the different distributions of endothelin receptors: ETA receptors may be present on the dopaminergic neurons, but ETB receptors on the glutamatergic neurons.
Horie
K
K
Laboratory of Nutritional Biochemistry, School of Food and Nutritional Sciences, University of Shizuoka, Japan.
Morita
A
A
Yokogoshi
H
H
D000818:Animals; D003342:Corpus Striatum / Q000187:drug effects / Q000378:metabolism; D004298:Dopamine / Q000378:metabolism*; D016232:Endothelins / Q000378:metabolism*; D018691:Excitatory Amino Acid Antagonists; D005971:Glutamates / Q000378:metabolism / Q000494:pharmacology; D008297:Male; D009474:Neurons / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar
D016232:Endothelins; D018691:Excitatory Amino Acid Antagonists; D005971:Glutamates; C011829:glutamic acid diethyl ester; D004298:Dopamine