The influences of leukotriene C4 on the metabolism of labelled glucose in uteri isolated from ovariectomized and from ovariectomized-estrogenized rats. Effects of indomethacin.
The effects of leukotriene C4 (LTC4), nordihydroguaiaretic acid (NDGA) and FPL-55712, on the metabolism of labelled glucose (U14C-glucose) in uteri isolated from spayed rats and from spayed-estrogenized rats, incubated in the presence and in the absence of indomethacin, were explored. Indomethacin (10(-6)M), enhanced significantly 14CO2 formation from labelled glucose, both in uteri from ovariectomized rats and in uteri from ovariectomized-estrogenized animals. In uteri from spayed not-estrogenized rats, expose 'in vitro' to indomethacin, NDGA (10(-5)M), an inhibitor of the 5-lipoxygenase, as well as FPL-55712 (10(-5)M), a LT antagonist, reduced significantly the enhanced metabolism of glucose evoked by indomethacin, an inhibitor of the cyclo- oxygenase. On the other hand, LTC4 (10(-7)M), augmented the metabolism of labelled glucose, reaching values even greater than those induced by indomethacin. In the spayed-estrogenized group LTC4 (10(-10)-10(-7)M) enhanced the formation of labelled CO2 from labelled glucose as much as indomethacin (10(-6)M) did, whereas neither NDGA nor FPL-55712 were effective. In addition, in uteri from ovariectomized-estrogenized rats, incubated with indomethacin, NDGA and FPL-55712, decreased the augmenting action of indomethacin on glucose metabolism, whereas LTC4 (10(-10)-10(-7)M) evoked a complete reversal of the inhibitory influence of NDGA on the formation of 14CO2. The force-going results suggest that tissue 5-lipoxygenase products, particularly LTC4, are involved in the metabolism of labelled glucose by rat uteri, mainly when the cyclo-oxygenase pathway is inhibited by indomethacin and the tissue is deprived of estradiol.(ABSTRACT TRUNCATED AT 250 WORDS)
Gonzalez
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Centro de Estudios Farmacológicos y de Principios Naturales (CEFAPRIN), Consejo Nacional de Investigaciones Cientificas y Técnicas (CONICET), Buenos Aires, Argentina.
Gimeno
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Gimeno
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D000818:Animals; D002245:Carbon Dioxide / Q000378:metabolism; D002867:Chromones / Q000494:pharmacology; D004958:Estradiol / Q000494:pharmacology*; D005260:Female; D005947:Glucose / Q000378:metabolism*; D066298:In Vitro Techniques; D007213:Indomethacin / Q000494:pharmacology*; D009637:Masoprocol / Q000494:pharmacology; D010052:Ovariectomy; D051381:Rats; D011919:Rats, Inbred Strains; D013189:SRS-A / Q000494:pharmacology*; D014599:Uterus / Q000201:enzymology / Q000378:metabolism*
D002867:Chromones; D013189:SRS-A; D002245:Carbon Dioxide; D004958:Estradiol; D009637:Masoprocol; C006312:FPL 55712; D005947:Glucose; D007213:Indomethacin