Norepinephrine induces apoptosis in skin melanophores by attenuating cAMP-PKA signals via alpha 2-adrenoceptors in the medaka, Oryzias latipes

Citation
N. Uchida-oka et M. Sugimoto, Norepinephrine induces apoptosis in skin melanophores by attenuating cAMP-PKA signals via alpha 2-adrenoceptors in the medaka, Oryzias latipes, PIGM CELL R, 14(5), 2001, pp. 356-361
Citations number
28
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Cell & Developmental Biology
Journal title
PIGMENT CELL RESEARCH
ISSN journal
0893-5785 → ACNP
Volume
14
Issue
5
Year of publication
2001
Pages
356 - 361
Database
ISI
SICI code
0893-5785(200110)14:5<356:NIAISM>2.0.ZU;2-S
Abstract
The density of skin melanophores in many teleost fish decreases during long -term adaptation to a white background. Using the medaka, Oryzias latipes, we previously reported that apoptosis is responsible for the decrease in me lanophores, and that a sympathetic neurotransmitter, norepinephrine (NE), i nduces their apoptosis in skin tissue cultures. In this study, we show that NT-induced apoptosis of melanophores is mediated by the activation of alph a2-adrenoceptors. Clonidine, an alpha2-adrenoceptor agonist, induced apopto tic melanophore death in skin organ culture, while phenylephrine, an alpha1 -adrenoceptor agonist, had no effect. NE-induced apoptosis was diminished b y an alpha2-adrenoceptor antagonist, yohimbine, but an alpha1-adrenoceptor antagonist, prazosin, did not abrogate the effect of NE. Furthermore, forsk olin inhibited NE-induced apoptosis, while an inhibitor of PKA, H-89, mimic ked the effect of NE. These results suggest that NE induces apoptosis in me lanophores by attenuating cAMP-PKA signaling via alpha2-adrenoceptors.