Effect of Insulin on the Healing of Bone Wounds in Albino Rats

¹ Department of Oral Pathology, Indiana University School of Dentistry, Indianapolis, Indiana

A review of the literature concerning the physiological properties of insulin has indicated that it might favorably influence wound-healing, since it could stimulate growth of individual cells, as well as cause increased anabolism of the organism as a whole. Previous experimental work concerning the effect of insulin on wound-healing has shown the possibility of a beneficial effect. The effect of systemically administered protamine-zinc insulin on the healing of bone wounds was studied by physical methods supplemented with roentgenologic and histologic evaluation.

Sixty-six male albino rats were subjected to a surgical operation wherein a uniform bone wound was made in the left femur. The animals were divided into 2 groups, and the experimental group received daily injections of protamine-zinc insulin. Blood-sugar determinations confirmed the systemic hypoglycemic effect of the insulin.

At the end of the 7-day healing period all the surviving animals were sacrificed, and their femora dissected out, radiographed, and their breaking strength tested. The breaking strengths were tested by means of a machine constructed especially for the purpose. Histologic studies were also made on some of the animals. No differences in the degree of healing could be detected by histologic study, roentgenographic study, or by breaking-strength tests.