Radiation-induced glomerular thrombus formation and nephropathy are not prevented by the ADP receptor antagonist clopidogrel.

Autor: te Poele JA; Division of Experimental Therapy, The Netherlands Cancer Institute, Amsterdam, The Netherlands., van Kleef EM, van der Wal AF, Dewit LG, Stewart FA
Jazyk: angličtina
Zdroj: International journal of radiation oncology, biology, physics [Int J Radiat Oncol Biol Phys] 2001 Aug 01; Vol. 50 (5), pp. 1332-8.
DOI: 10.1016/s0360-3016(01)01617-0
Abstrakt: Purpose: To assess the effects of kidney irradiation on glomerular adenosine diphosphatase (ADPase) activity and intraglomerular microthrombus formation, and their correlation to the development of renal functional impairment.
Methods and Materials: C3H/HenAf-nu(+) mice were given single-dose or fractionated kidney irradiations. Glomerular ADPase activity was measured using a cerium-based histochemical method. Microthrombus formation within the glomeruli was assessed by a semiquantitative immunohistochemical analysis of fibrinogen/fibrin deposits. Renal function was assessed by the [(51)Cr]EDTA retention assay.
Results: The ADPase activity was significantly reduced, to approximately 50% of pretreatment value, 4--40 weeks after 10--16 Gy single-dose irradiation and at 44 weeks after 20 x 2 Gy. No dose--effect relationship was found. An approximately fourfold increase in glomerular fibrinogen/fibrin staining was observed at 1 year after irradiation. This increase was not influenced by treating the mice with daily, oral clopidogrel, a platelet ADP receptor antagonist, which reduced platelet aggregation by more than 75%. Radiation-induced impairment of glomerular filtration was also not affected by the clopidogrel treatment.
Conclusion: These data indicate that irradiation significantly reduced glomerular ADPase activity, which correlated with an increased glomerular fibrinogen/fibrin deposition. We were not able to reduce these prothrombotic changes, nor to protect against radiation nephropathy, by pharmacological intervention with an ADP-receptor antagonist.
Databáze: MEDLINE