Endothelin-1 in periaqueductal gray area of mice induces analgesia via glutamatergic receptors.
The aim of the study was to examine whether endothelin-1 (ET-1) injected into dorsolateral periaqueductal gray (PAG) area of mice produces antinociception. ET-1, from 1 to 4 pmol/mouse, induced antinociceptive effect in a dose-dependent manner. This antinociceptive effect was prevented by NMDA receptor antagonists (2-APV and MK-801) injected in the same area (2-APV) or by intraperitoneal route (MK-801). CNQX, a non-NMDA receptor antagonist, did not inhibit the ET-1 effects. Prazosin, an alpha 1-adrenergic blocking agent, also prevented the ET-1 antinociceptive effect. We suggest that the activation of NMDA glutamatergic receptors in the PAG area may be a necessary step for ET-1 induced antinociception.
D'Amico
M
M
Institute of Pharmacology and Toxicology, Faculty of Medicine and Surgery, II University of Naples, Italy.
Berrino
L
L
Maione
S
S
Filippelli
A
A
de Novellis
V
V
Rossi
F
F
D015763:2-Amino-5-phosphonovalerate / Q000494:pharmacology; D018750:6-Cyano-7-nitroquinoxaline-2,3-dione / Q000494:pharmacology; D000317:Adrenergic alpha-Antagonists / Q000494:pharmacology; D000700:Analgesics / Q000494:pharmacology*; D000818:Animals; D016291:Dizocilpine Maleate / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D019332:Endothelin-1 / Q000494:pharmacology*; D018691:Excitatory Amino Acid Antagonists / Q000494:pharmacology; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D010487:Periaqueductal Gray / Q000187:drug effects*; D011224:Prazosin / Q000494:pharmacology; D017470:Receptors, Glutamate / Q000187:drug effects*
D000317:Adrenergic alpha-Antagonists; D000700:Analgesics; D019332:Endothelin-1; D018691:Excitatory Amino Acid Antagonists; D017470:Receptors, Glutamate; D016291:Dizocilpine Maleate; D018750:6-Cyano-7-nitroquinoxaline-2,3-dione; D015763:2-Amino-5-phosphonovalerate; D011224:Prazosin