In vivo effect of interleukin-1α on colony-stimulating factor-1 gene expression in the dental follicle of the rat molar

Interleukin-1α (IL-1α) acts in vitro to enhance the gene expression of colony-stimulating factor-1 (CSF-1) of dental follicle cells. Because the dental follicle is required for tooth eruption and because CSF-1 appears to be a key molecule in initiating eruption, it was the aim of this study to determine if IL-1α could enhance the expression of the CSF-1 gene in the dental follicle in vivo. To determine this, rats were injected with IL-1α at different ages postnatally and the total RNA was isolated from the dental follicles of the first mandibular molars. Reverse transcription-polymerase chain reaction showed that IL-1α enhanced the expression of CSF-1 in the follicle. Thus, IL-1α may play a part in the cascade of molecular signals that initiate eruption by its effect upon the CSF-1 gene.