TY - JOUR
T1 - Dual effect of isoprostanes on the release of [3H]D-aspartate from isolated bovine retinae
T2 - Role of arachidonic acid metabolites
AU - Opere, Catherine A.
AU - Zheng, Wei Dong
AU - Huang, Jifan
AU - Adewale, Adeniran
AU - Kruglet, Michael
AU - Ohia, Sunny E.
PY - 2005/1/1
Y1 - 2005/1/1
N2 - The effect of 8-isoprostanes on potassium (K+)-depolarization- evoked release of [3H]D-aspartate from bovine isolated retinae was investigated. Isolated bovine retinae were prepared for studies of K +-evoked release of [3H]D-aspartate using the Superfusion Method. Low concentrations of 8-isoPGF2α (1-100 nM) inhibited whereas higher concentrations of this 8-isoprostane (100 nM-30 μM) enhanced K+-induced [3H]D-aspartate overflow. The excitatory effect of 8-isoPGF2α was mimicked by thromboxane receptor agonist, U-46619 and blocked by thromboxane receptor antagonist, SQ 29,548 (10 μM). Pretreatment of tissues with the cyclooxygenase (COX) inhibitor, flurbiprofen unmasked an inhibitory effect of high concentrations of 8-isoPGF 2α (1-30 μM) on [3H]D-aspartate release that was attenuated by AH 6809 (10 μM). In conclusion, 8-isoPGF2α exhibits a dual regulatory effect on K+-induced [3H]D- aspartate release in isolated bovine retinae. The inhibitory action caused by 8-isoPGF2α is due to the activation of EP1/EP 2 receptors while the excitatory effects are due to the activation of thromboxane receptors.
AB - The effect of 8-isoprostanes on potassium (K+)-depolarization- evoked release of [3H]D-aspartate from bovine isolated retinae was investigated. Isolated bovine retinae were prepared for studies of K +-evoked release of [3H]D-aspartate using the Superfusion Method. Low concentrations of 8-isoPGF2α (1-100 nM) inhibited whereas higher concentrations of this 8-isoprostane (100 nM-30 μM) enhanced K+-induced [3H]D-aspartate overflow. The excitatory effect of 8-isoPGF2α was mimicked by thromboxane receptor agonist, U-46619 and blocked by thromboxane receptor antagonist, SQ 29,548 (10 μM). Pretreatment of tissues with the cyclooxygenase (COX) inhibitor, flurbiprofen unmasked an inhibitory effect of high concentrations of 8-isoPGF 2α (1-30 μM) on [3H]D-aspartate release that was attenuated by AH 6809 (10 μM). In conclusion, 8-isoPGF2α exhibits a dual regulatory effect on K+-induced [3H]D- aspartate release in isolated bovine retinae. The inhibitory action caused by 8-isoPGF2α is due to the activation of EP1/EP 2 receptors while the excitatory effects are due to the activation of thromboxane receptors.
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U2 - 10.1007/s11064-004-9694-3
DO - 10.1007/s11064-004-9694-3
M3 - Article
C2 - 15756941
AN - SCOPUS:13844292772
VL - 30
SP - 129
EP - 137
JO - Neurochemical Research
JF - Neurochemical Research
SN - 0364-3190
IS - 1
ER -