RESUMO
The mouse granular convoluted tubules of submandibular gland of laboratory mouse are releasing a range of biologically active peptides (renin, neural growth factor and others) into both the saliva and blood circulation, the males producing it in a larger extent than females. Recently, several from respective peptides were identified to be endogenous ones and brain-related. The present work was aimed to utilise submandibular gland/SMG auto- and isotransplants regenerating in murine brain as a possibly local source of peptides. Experimentally, the newborn and juvenile matured white A breeded mice of both sexes were used. Glandular grafts were grafted into brain parenchyma or CSF spaces. Laboratory animals have then been perished during the first 6 weeks after transplantation, and the transplants so acquired evaluated as serial frontal sections embedded in paraffin and H.E. stained by light microscopy. Also cryocate sections were incubated in order to detect the presence of alkaline phosphatase (AP) and succinic dehydrogenase/(SDH). It was stated experimentally that both mentioned SMG grafts underwent the survival and development intracerebrally. Some first regressive changes were gradually replaced by glandular proliferation and lobular neomorphogenesis having been more pronounced in osotransplants. The proliferative period was characterized by cellular mitoses, multiplication of duct-like and terminal tubulous structures of newly formed glandular lobules. Partially, the isotransplants display the transformation of proliferation stage into that of cellular cytodifferentiation followed by gradual appearance of striated ducts, acini and even granular convoluted tubules on the 5th week after transplantation. Also the reoccurrence of enzyme activities in the transplant parenchyma after their initially total disappearance is testifying of both proliferation and cytodifferentiation developed gradually. During the first days of implantation, the revascularization of grafts occurs, those being high in AP endothelial activity of vessels newly formed. This is to conclude that higher proliferative intensity of isotransplants and their exclusive cytodifferentiation demonstrate that an undifferentiated murine SMG which can develop itself ontogenetically is more effective graft than a SMG differentiated fully. On the next stage, the development of glandular grafts will be studied with more delay after transplantations. Also the enzyme implementation of new parenchymatous components is to be elucidated. Further experimentation is planified as to influencing intracerebral SMG graft development with administration of hormones and isoproterenol to laboratory animals.
