Early and long-term effects of radiation on intercellular adhesion molecule 1 (ICAM-1) expression in mouse urinary bladder endothelium.
The aim was to assess the effect of irradiation on intercellular adhesion molecule 1 (ICAM-1) expression in endothelial cells of vessels in mouse urinary bladder and to compare endothelial ICAM-1 expression with changes in bladder function (storage capacity) during the early and late radiation response phases. Female C3H/Neu mice were irradiated with doses of either 20 or 0 Gy. For assessment of ICAM-1 expression, which was measured by the intensity of the immunohistochemical staining signal in bladder endothelium, an arbitrary semiquantitative score (0 - 3) was applied. Bladder storage function was assessed by transurethral cystotonometry. A positive functional radiation response, defined as a reduction in bladder capacity by > 50%, between days 0 and 15 or 16 and 30 was found in 40 and 64% of the animals, respectively. A late functional response was observed in 71% of the animals sacrificed after day 180. Minor constitutive expression of ICAM-1 was observed in bladder endothelial cells. After irradiation, an increase in staining signal by day 2, with a maximum on day 4, and on days 16 - 28 was found, which preceded the functional radiation effects. A permanent increase in ICAM-1 staining signal was observed in the late phase on top of an age-related rise. ICAM-1 expression was significantly higher in animals with a positive late response on day 90, i.e. during the initial late phase. Irradiation induces significant early and chronic variations in ICAM-1 expression in bladder endothelium, which preceded the functional response. This suggests that endothelial ICAM-1 is involved in the pathogenesis of both the early and late phases of radiation-induced urinary bladder effects.
Jaal
J
J
Klinik und Poliklinik für Strahlentherapie und Radioonkologie, Carl Gustav Carus der Technischen Universität, Dresden, Germany. Jana.Jaal@klinikum.ee
Dörr
W
W
D000818:Animals; D004727:Endothelium / Q000502:physiology / Q000528:radiation effects; D005260:Female; D007150:Immunohistochemistry; D018799:Intercellular Adhesion Molecule-1 / Q000096:biosynthesis*; D051379:Mice; D008809:Mice, Inbred C3H; D011832:Radiation Injuries / Q000235:genetics / Q000503:physiopathology*; D001743:Urinary Bladder / Q000502:physiology* / Q000528:radiation effects*; D014563:Urodynamics
D018799:Intercellular Adhesion Molecule-1