Effects of cortisone acetate, methylprednisolone and medroxyprogesterone on wound contracture and epithelization in rabbits

Standardized flank wounds were made on 20 rabbits divided into the following five groups: Group 1 served as controls, Group 2 were given cortisone acetate 6.25 mg/kg/day (I.M.), Group 3--methylprednisolone (Solu-Medrol) 1 mg/kg/day, Group 4--medroxyprogesterone (Depo-Provera) 35 mg/kg/day, Group 5--methylprednisolone 1 mg/kg/day and medroxyprogresterone 35 mg/kg/day. Wound contracture and epithelization was measured by planimetry of photographs taken twice weekly; weekly weights were recorded, and the maturation phase of wound healing followed in the control and methylprednisolone groups. All three steroids prolonged the latent phase of wound healing, slowed the rate and decreased the total amount of contracture. Cortisone showed the most inhibition of wound contracture and was the only steroid to inhibit epithelization suggesting it may have a slightly different or more potent mode of action. When the methylprednisolone group was followed for seven weeks on daily injections, the maturation phase of wound healing was inhibited, and this inhibition persisted during the next nine weeks after the drug was withdrawn. Only the control and the medroxyprogesterone group gained weight. Combining medroxyprogesterona and methylprednisolone resulted in the severest weight loss of 20% with a 60% mortality.