The Effects of the Angiotensin Converting Enzyme Inhibitor Enalapril and the Angiotensin II Type 1 Receptor Blocker Losartan on Fracture Healing in Rats

Abstract

Purpose: Angiotensin converting enzyme inhibitors (ACEI) and type I angiotensin receptor blockers (ARB) have been shown to exert significant effects on bone tissue via a local renin-angiotensin-aldosterone system (RAS). Th e aim of our study was to delineate their influences on fracture healing process.Methods: Sixty adult male Wistar Albino rats were divided into three groups. After undergoing surgical femoral fracture and fi xation, the ACEI group received 10 mg/kg of Enalapril, the ARB group received 10 mg/kg of Losartan and the Control group did not receive any medication. Fracture healing was evaluated at second and fift h postoperative weeks by the Lane-Sandhu radiological staging system and by histological scoring system of Huoet al. ACE expression in fracture callus was studied by immunohistochemistry.Results: Both ACEI and ARB groups showed less fibrous tissue in the fracture area at the second week, but the histologic score differences were significant only between Control and ARB groups. At the fift h week, however, both radiological and histological scores for the ACEI group were significantly higher than both ARB and Control groups, while the scores for ARB and Control groups were similar. The presence of ACE expression in fracture callus was also observed. Conclusion:ACEIs had significant positive effects on fracture repair. Losartan failed to display these stimulatory effects, which suggests that local RAS in bone tissue exerts its actions via alternative receptors or pathways than the AT1 receptor.

Morphometric and histologic characterization of alveolar bone from hypertensive patients

“…Hypertension also affects alveolar bone quality in a rat model suggesting a possible impact on implant stability in the early phase of osseointegration. Antihypertensive drugs including losartan, enalapril, and captopril can prevent catabolic changes in bone turnover including alveolar bone . We therefore proposed that antihypertensive drugs can preserve alveolar bone quality at future implant sites.…”

“…Antihypertensive drugs including losartan, enalapril, and captopril can prevent catabolic changes in bone turnover including alveolar bone. 22,28,29 We therefore proposed that antihypertensive drugs can preserve alveolar bone quality at future implant sites. In support of this hypothesis, we report here that hypertensive patients treated with antagonists of the reninangiotensin system have regular alveolar bone with respect to bone structure and histological parameters.…”

Cutaneous inflammation differentially regulates the expression and function of Angiotensin‐II types 1 and 2 receptors in rat primary sensory neurons

“…This rendered an effective average dose of losartan of 20 mg/Kg/day. This dosage and length of treatment was used elsewhere to examine numerous physiologically relevant processes (Bayar et al ; Kamber et al ; Akershoek et al ). The second group ( n = 6) received oral losartan as the first group, but from day 25 to 28 also received a daily i.p.…”

Ginkgo Biloba improves bone formation during fracture healing: an experimental study in rats

“…, 12 However, there have been no studies to date that have explored the effects of G. biloba on fracture healing. …”