Abstract
This study was carried out to investigate the effect of tinoridine (2-amino-3-ethoxycarbonyl-6-benzyl-4, 5, 6, 7-tetrahydrothieno [2, 3-c] pyridine), a non-steroidal antiinflammatory drug, on the lipid peroxidation and renin release in the renin granule fraction. The renin granule fraction was prepared from the kidney cortex homogenate by a discontinuous sucrose density gradient centrifugation. Incubation of this fraction at 37°C resulted in an increase in lipid peroxide formation, accompanied by increased release of renin from the granules. When the renin granule fraction was incubated with 50 μM tinoridine at 37°C, lipid peroxide formation in this fraction was completely inhibited. Simultaneously, the rate of renin release from the granules was significantly suppressed. Tinoridine, at concentrations from 5 μM up to 100 μM, produced a concentration-dependent inhibition on the simultaneous increases in lipid peroxide formation and renin release induced by 50 μM ascorbic acid in the renin granule fraction. On the other hand, indomethacin, hydrocortisone and prednisolone, which had no ability to inhibit the lipid peroxidation in the renin granule fraction, did not influence the release of renin from the granules. The results suggest that tinoridine suppresses renin release by inhibiting the oxidative disintegration of membranes of renin granules.
