Alterations of angiotensin II receptor levels in sutured wounds in rat skin

Angiotensin II receptor levels have been shown to vary with postoperative time in tissue harvested from full-thickness dermal excisional wounds on adult rats. This study examined the expression of AII receptors in a sutured wound model. Two full-thickness incisional wounds were made in the dorsal skin of adult Sprague-Dawley rats and sutured immediately under general anesthesia. The wound tissues were harvested at 0, 0.5, 1, 2, 4, 24 h and on days 2, 3, 4, 5, 7, and 10 after the wounding. The levels of I-125-Sar(1).Ile(8)-AII bound to membrane preparations of the wound tissues decreased at early time points (from 0.5 to 4 h) increased from day 1 to day 7, and returned to nonsurgical levels by day 10. Competitive binding studies showed that the receptors were predominantly of the AT1 receptor subtype. These results suggest that an immediate and transient reduction in AII receptor expression occurred after wounding, followed by an increase in the number of AII receptors that was maintained for 5 to 7 days postoperatively. Because these data are consistent with those observed after excisional wounding, temporal changes in AII receptor expression may be integral to the process of wound healing.