TY - JOUR
T1 - Changes in renal haemodynamics induced by indomethacin in the rat involve cytochrome P450 arachidonic acid-dependent epoxygenases
AU - Caron, N.
AU - El Hajjam, A.
AU - Declèves, A. E.
AU - Joly, E.
AU - Falck, J. R.
AU - Kramp, Ronald
PY - 2004/10
Y1 - 2004/10
N2 - 1. A significant renal vasodilation was observed previously after an acute cyclo-oxygenase (COX) inhibition induced with indomethacin. Because this effect could be due to COX-dependent intrarenal metabolization of arachidonic acid through cytochrome P450 (CYP450) pathways, the aim of the present study was to investigate, in vivo, possible interactions between COX and CYP450 mono-oxygenases. 2. Mean arterial pressure (MAP) and renal blood flow (RBF), using an electromagnetic flow transducer for RBF evaluation, were measured continuously in 71 anaesthetized eovolaemic rats. Appropriate solvents (vehicle), 3 mg/kg indomethacin, 17-octadecynoic acid (17-OBYA; 2 mmol/L), either miconazole (MI; 1.5 mmol/L) or N-methylsulphonyl-6-(2-propargyloxyphenyl) hexanamide (MS-PPOH; 5 mg/kg) and N′-hydroxyphenylformamidine (HET0016; 5 or 10 mg/kg) were administered to inhibit either COX, CYP450 monooxygenases, epoxygenases or hydroxylase, respectively. The CYP450 and COX inhibitors were also combined as follows: 17-ODYA/indomethacin, MI (or MS-PPOH)/indomethacin, HET0016/indomethacin and indomethacin/HET0016. 3. Mean arterial pressure and RBF were not modified by vehicle, 17-ODYA or MI (or MS-PPOH). However, MAP decreased slightly (P < 0.05; paired t-test, 5 d.f.) and RBF increased transiently (P < 0.05; ANOVA, 5 d.f.) after HET0016. In contrast, MAP decreased by 10 mmHg (P < 0.05) and RBF increased by 10% (P < 0.05) after indomethacin. This enhancement was prevented by 17-ODYA or MI (or MS-PPOH), but not by HET0016. Moreover, RBF increased step-wise to 21% in the indomethacin/HET0016 experiment (P < 0.05). Consequently, changes from baseline in renal vascular resistance differed among treatments, averaging -2 ± 3 (vehicle), -13 ± 3 (indomethacin; P < 0.05 vs vehicle), -4 ± 3 (17-ODYA/indomethacin), -3 ± 4 (MI or MS-PPOH/indomethacin), -15 ± 3 (HET0016/indomethacin; P < 0.05) and -22 ± 4% (indomethacin/HET0016; P < 0.05). 4. In conclusion, these results demonstrate that the renal vasodilation induced by indomethacin can be prevented by prior inhibition of CYP450 mono-oxygenases and further suggest that the CYP450 epoxygenases pathway may prevail.
AB - 1. A significant renal vasodilation was observed previously after an acute cyclo-oxygenase (COX) inhibition induced with indomethacin. Because this effect could be due to COX-dependent intrarenal metabolization of arachidonic acid through cytochrome P450 (CYP450) pathways, the aim of the present study was to investigate, in vivo, possible interactions between COX and CYP450 mono-oxygenases. 2. Mean arterial pressure (MAP) and renal blood flow (RBF), using an electromagnetic flow transducer for RBF evaluation, were measured continuously in 71 anaesthetized eovolaemic rats. Appropriate solvents (vehicle), 3 mg/kg indomethacin, 17-octadecynoic acid (17-OBYA; 2 mmol/L), either miconazole (MI; 1.5 mmol/L) or N-methylsulphonyl-6-(2-propargyloxyphenyl) hexanamide (MS-PPOH; 5 mg/kg) and N′-hydroxyphenylformamidine (HET0016; 5 or 10 mg/kg) were administered to inhibit either COX, CYP450 monooxygenases, epoxygenases or hydroxylase, respectively. The CYP450 and COX inhibitors were also combined as follows: 17-ODYA/indomethacin, MI (or MS-PPOH)/indomethacin, HET0016/indomethacin and indomethacin/HET0016. 3. Mean arterial pressure and RBF were not modified by vehicle, 17-ODYA or MI (or MS-PPOH). However, MAP decreased slightly (P < 0.05; paired t-test, 5 d.f.) and RBF increased transiently (P < 0.05; ANOVA, 5 d.f.) after HET0016. In contrast, MAP decreased by 10 mmHg (P < 0.05) and RBF increased by 10% (P < 0.05) after indomethacin. This enhancement was prevented by 17-ODYA or MI (or MS-PPOH), but not by HET0016. Moreover, RBF increased step-wise to 21% in the indomethacin/HET0016 experiment (P < 0.05). Consequently, changes from baseline in renal vascular resistance differed among treatments, averaging -2 ± 3 (vehicle), -13 ± 3 (indomethacin; P < 0.05 vs vehicle), -4 ± 3 (17-ODYA/indomethacin), -3 ± 4 (MI or MS-PPOH/indomethacin), -15 ± 3 (HET0016/indomethacin; P < 0.05) and -22 ± 4% (indomethacin/HET0016; P < 0.05). 4. In conclusion, these results demonstrate that the renal vasodilation induced by indomethacin can be prevented by prior inhibition of CYP450 mono-oxygenases and further suggest that the CYP450 epoxygenases pathway may prevail.
KW - 20-hydroxyeicosatetraenoic acid
KW - Cyclo-oxygenase
KW - Cytochrome P450 epoxygenases
KW - Eicosanoids
KW - Haemodynamics
KW - Indomethacin
KW - N′-hydroxyphenylformamidine
KW - Renal blood flow
KW - Renal vascular resistance
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U2 - 10.1111/j.0305-1870.2004.04066.x
DO - 10.1111/j.0305-1870.2004.04066.x
M3 - Article
C2 - 15554908
AN - SCOPUS:9144275014
SN - 0305-1870
VL - 31
SP - 683
EP - 690
JO - Clinical and Experimental Pharmacology and Physiology
JF - Clinical and Experimental Pharmacology and Physiology
IS - 10
ER -