Testicular nitric oxide levels after unilateral testicular torsion/detorsion in rats pretreated with caffeic acid phenethyl ester

Nitric oxide (NO) plays an important role in modulating blood flow in norma l and in several pathological conditions, and its levels seem to change wit h ischemia-reperfusion injuries. Caffeic acid phenethyl ester (CAPE), an ac tive component of propolis, exhibits antioxidant properties. This experimen tal study was designed to determine the changes in NO levels and the effect of CAPE on NO levels after testicular torsion/ detorsion in rats. Thirty-f ive adult male albino rats were divided into four groups: sham operation (n = 8), torsion (n = 9), saline/detorsion (n = 9), and CAPE/detorsion (n = 9 ). Rats in the sham operation group were killed after the testes were handl ed without torsion. Rats in the torsion group were killed after 720 degrees clockwise testicular torsion for 2 h. CAPE was administered 30 min before detorsion in the CAPE/detorsion group and saline was administered in the sa line/detorsion group. After 4 h of testicular detorsion in both of these gr oups, the rats were killed and bilateral orchiectomy was performed to deter mine the tissue levels of NO. The level of NO in the torsion group (113.77 +/- 33.18 nmol/g protein) was significantly higher than that of the sham op eration group (64.53 +/- 29.64 nmol/g protein). In the saline/detorsion gro up, the NO level (31.26 +/- 12.58 nmol/g protein) was significantly lower t han in the torsion and sham operation groups. CAPE administration in the CA PE/detorsion group seemed to raise the NO level (72.63 +/- 23.87 nmol/g pro tein) above the level of the sham operation group. Contralateral testes wer e not affected by the torsion/detorsion processes performed on the ipsilate ral testes. These results show that NO levels increase with torsion and dec rease with detorsion. CAPE administration seems to increase tissue NO level s and this may be important for protecting the testes from torsion/detorsio n injuries.