effect of prostaglandin E2 [PG E2] modulation on fracture repair: a preliminary study

ABSTRACT

Fracture repair is a complex process mediated by local regulators including PG E2. A preliminary study was undertaken on the effect of exogenous PG E2 on fracture repair to clarify the PG E2 controvarsed action of being potent bone stimulator resorbant autocoid [local hormone] aiming to reduce the morbidity of fracture healing by accelerating the healing process and shortening the repair period. fourty three male rabbits of average weight 2.0 kgms were selected and were classified into four comparable groups of ten rabbits after loss of three during the study. The control group was given daily s.c. 1 ml placebo. The PG E2 group received daily s.c. 5 ugm/kg body weight PG E2 [Dinoprostine]. L.A.S. group received daily s.c. 12.5 mg L.A.S. [Aspegic] 1kg. The PG E2-L.A.S. group received daily s.c. dose of 12.5 mgm L.A.S. and 5 U.gm. PG E2. The PG E2 dose level used showed prolonged healing period and modified repair pattern in favour of production of chondroosseouscallus with significant blood biochemical changes. This result was not apparent in the control group and was less apparent in the PG E2-L.A.S. group. It seems that the PG E2 delayed healing effect could be counteracted by L.A.S. L.A.S. group showed retarded healing process and small callus formed of thin bone trabeculae with significant blood biochemical changes. L.A.S. was not beneficial for fracture healing. In conclusion, PG E2 in the dose used was non beneficial to fracture repair and in a higher dose it could have important role in delay or non union of the fracture. This study suggest that the rate and type of bone healing activity could markedly be PG E2 dose related and dependent i.e. potent bone stimulator in small dose and bone inhibitor in higher dose