In vivo microvascular response of murine cutaneous muscle to ibuprofen-releasing polyurethane foam

In view of their pain-relieving effect, the non steroidal anti-inflammatory drugs are more and more used as a pain-reducing component in modern wound dressings. To analyse the effect on new blood vessel growth, implants from Biatain Ibu, a polyurethane foam containing ibuprofen, were inserted into the dorsal skinfold chamber of BALB/c mice. Implants from ibuprofen-free polyurethane foam Biatain served as controls (n = 10 per group). Blood vessel growth and the functional vessel density (FVD) as a parameter for microvascularization of implant's border zone were assessed by intravital fluorescence microscopy (IVFM). IVFM was performed on days 3, 7 and 12 after implantation. Direct comparison showed no significant differences in FVD (mm/mm(2)) for the border zone of the ibuprofen-releasing implants versus controls on day 3 (185.49 +/- 4.75 versus 197.17 +/- 5.21) and day 7 (229.60 +/- 8.53 versus 247.99 +/- 5.39). However, the IVFM showed a significant increased FVD for ibuprofen-releasing implants (301.30 +/- 8.44 versus 279.24 +/- 5.78) on day 12 (P < 0.05). Also, a significant increase of FVD was detected for the ibuprofen-releasing implants throughout the implantation time of 12 days. This study shows that local release of small-dose ibuprofen from a polyurethane dressing does not decrease new blood vessel growth during the implantation time of 12 days. In the end, the microvascularization of implant's border zones in both groups was found comparatively undisturbed.