The effect of formocresol on hamster connective tissue cells, a histologic and quantitative radioautographic study with proline-H3.

The reaction to formocresol of connective tissue cells has been examined in sponge implants and femur wounds, by means of quantitative radioautography following proline-H3 injection. For twenty-four hamsters, a sponge implant on the dorsum of the neck and a surgical opening in the right femur were prepared. Formocresol was diluted to l/50 of a normal concentration for the sponge implant study and the normal concentration was tested on the femur. The time intervals from application of the drug to sacrifice were 5 hr, 1 day, 3 and 10 days, and 1 month. Proline-H3 was injected 4 or 24 hr prior to sacrifice. Three animals were used for the scintillation counting of blood level of tritium from 2.5 min to 6 days. The tissues were fixed in Bouin’s solution, embedded and sectioned in a routine manner. The sections were coated with Kodak NTB3 emulsion and exposed for suitable lengths of time. Formocresol used in l/50 concentration caused degeneration of cells in the immediate vicinity of the sponge implant as judged by histology and radioautographic grain counts. However, in all animals treated with formocresol a definite reduction in the number of infiltrating intlammatory cells was observed. By the tenth day both the experimental and control sponges showed a comparable recovery of the connective tissue ingrowth. This was also true for the repair in the femur wound area. It was concluded that formocresol does not interfere with prolonged recovery of connective tissue and might suppress initial inflammatory response, significantly.