The radioprotective activities of turpentine-induced inflammation and alpha2-macroglobulin: the effect of dexamethasone on the radioprotective efficacy of the inflammation.
This work was aimed at the radioprotective efficacy of turpentine oil (TO), alpha2-Macroglobulin (alpha2-M), Amifostine (Ami) and/or dexamethasone (Dex). These agents were administrated, alone or in combination, prior to irradiation of rats with 6.7 Gy (LD(50/30)). The survival was recorded daily for 4 weeks after irradiation and body weight, peripheral leukocytes and thrombocytes were measured. The plasma concentration of alpha2-M and other acute phase proteins were determined by crossed immunoelectrophoresis. All rats receiving alpha2-M and Ami alone or in combination survived the radiation injury, whereas the rate of survival of TO-treated rats was 90%. Radiation and therapy-induced changes in the expression of acute phase protein genes were atypical for the acute phase reaction. Dex alone was lethal for 45% and 55% of control and irradiated rats, respectively. Pretreatment with 1mg Dex reduced radioprotective efficacy of TO and Ami to 30% and 40%, respectively. Given together TO and Ami provided 70% protection to rats receiving Dex. The TO and alpha2-M enhanced the rate of survival from 50% to 90% and 100%, respectively. In the presence of 1mg Dex the TO-induced radioprotectors and Ami exhibited radiosensitizing rather than radioprotecting activities.
Sevaljević
Ljiljana
L
Vinca Institute of Nuclear Sciences, Department of Molecular Biology and Endocrinology, PO Box 522, 11001 Belgrade, Yugoslavia.
Dobrić
Silva
S
Bogojević
Desanka
D
Petrović
Miodrag
M
Koricanać
Goran
G
Vulović
Mojca
M
Kanazir
Dusan
D
Ribarac-Stepić
Nevena
N
D004999:Amifostine / Q000494:pharmacology; D000818:Animals; D003907:Dexamethasone / Q000494:pharmacology*; D005938:Glucocorticoids / Q000494:pharmacology*; D007249:Inflammation / Q000139:chemically induced* / Q000503:physiopathology*; D008297:Male; D011835:Radiation Protection / Q000379:methods; D011837:Radiation-Protective Agents / Q000494:pharmacology*; D011838:Radiation-Sensitizing Agents / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D014425:Turpentine / Q000494:pharmacology*; D014916:Whole-Body Irradiation / Q000401:mortality; D000511:alpha-Macroglobulins / Q000494:pharmacology*
D005938:Glucocorticoids; D011837:Radiation-Protective Agents; D011838:Radiation-Sensitizing Agents; D000511:alpha-Macroglobulins; D003907:Dexamethasone; D004999:Amifostine; D014425:Turpentine