Consequences of long-term selenium-deficient diet on the prostacyclin and thromboxane release from rat aorta.
It is known that peroxides, which are increased during Se deficiency because of reduced glutathione peroxidase (GSH-Px) activity, can influence the prostacyclin I2/thromboxane A2 (PGI2/TXA2) ratio. In this study we analyzed the PGI2 and TXA2 formation of aortas of long-term Se-deficient rats. Despite low GSH-Px activity in the Se-deficient group, the basal PGI2 and TXA2 formation was not different versus control animals (PGI2: 2295+/-1134 pg/mg vs 2940+/-1134 pg/mg; TXA2: 3.83+/-1.06 pg/mg vs 5.67+/-2.99 pg/mg). However, we checked the capacity of the aortas of Se-deficient rats to compensate for a suddenly increased peroxide concentration. After peroxide stimulation, the PGI2 release was significantly lower in the Se-deficient group compared to the control group (PGI2: 3507+/-1829 pg/mg vs 7986+/-2636 pg/mg). Again, the TXA2 release did not show any differences. The release ratio of PGI2/TXA2 decreased under peroxide stress in Se-deficient animals. Although long-term Se deficiency showed a relatively well-balanced metabolism under resting conditions, sudden stress, accompanied by an excessive radical production, cannot be compensated.
Haberland
A
A
Medizinische Klinik (Kardiologie, Angiologie, Pneumologie), Humboldt-Universität, Berlin, Germany.
Neubert
K
K
Kruse
I
I
Behne
D
D
Schimk
I
I
D000818:Animals; D001011:Aorta / Q000201:enzymology / Q000378:metabolism*; D003677:Deficiency Diseases / Q000378:metabolism*; D011464:Epoprostenol / Q000378:metabolism*; D005979:Glutathione Peroxidase / Q000378:metabolism; D066298:In Vitro Techniques; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D012643:Selenium / Q000172:deficiency*; D013928:Thromboxane A2 / Q000378:metabolism*
D013928:Thromboxane A2; D011464:Epoprostenol; D005979:Glutathione Peroxidase; D012643:Selenium