Effects of prior culture or isoproterenol injections on the regeneration of rat submandibular gland autografts.

This study compares the acinar cell regenerative response in submandibular gland (SMG) autografts that were cultured before grafting to the rat tongue with the acinar cell regenerative response in direct SMG autografts to the tongue. In addition, the effects of isoproterenol on direct SMG autografts were studied. A portion of the left SMG was excised from each rat and cut into fragments which were autografted either immediately into the middle one-third of the rat's tongue; or were cultured for 1, 4, or 7 days and then autografted to the donor's tongue. After 8 weeks the rats were killed and the tongues were removed and processed for light microscopic study. The histologic preparations showed evidence of cytodifferentiation into acinar cells in four of the previously cultured SMG autografts. Some of the direct SMG autografts did not contain acinar cells, whereas other direct SMG autografts contained numerous acinar cells and even striated ducts. In the SMG autografts that were cultured for 1 day before autografting and in the direct SMG autografts, the most pronounced regenerative responses were seen in autografts that contained ductlike structures that were apparently connected to the epithelial surface of the tongue. Lastly, isoproterenol appeared to accelerate the regenerative response in some of the direct SMG autografts, and the drug caused acinar cell hypertrophy in two of the direct SMG autografts.