Objective: To explore the feasibility of evaluating complete ischemia-reperfusion injury (IRI) of the testis by contrast-enhanced ultrasonography with microbubbles (MB) targeted to P-selectin (MBp) in rabbits.
Methods: We randomly divided 30 healthy adult rabbits into five groups of equal number (control, 0.5 h IRI, 1 h IRI, 2 h IRI, and 4 h IRI), prepared phospholipid MB and MBp, and performed contrast-enhanced ultrasonography of the bilateral testes with MB or MBp at an interval of 20 min at different times after IRI. When MB or MBp disappeared completely in the healthy testis at 4 to 5 min after intravenous injection, we recorded the power of the first frame (F-P) in the IRI testes followed by immunohistochemical staining of the testis tissue.
Results: CEU with MBp achieved a significantly higher F-P than that with MB in all the IRI groups (P < 0.05), which was (8.34 +/- 1.20) versus (1.87 +/- 0.25) 10(-5) AU at 2 hours, but there was no significant difference between MB and MBp in the control rabbits (0 AU, P > 0.05). Immunohistochemistry showed a significantly time-dependent increase in the expression of P-selectin in the vascular endothelial cells of the IRI testes, but not in those of the control.
Conclusion: Contrast-enhanced ultrasonography with MBp can be used to evaluate the inflammatory reaction of testicular ischemia-reperfusion injury.