cell surface molecular differentiation during rat adenohypophysis morphogenesis using lectin histochemistry

introduction: it is well known that glycoconjugates on the cell surface of embryonic cells as well as extracellular matrix (ecm) are involved in many developmental phenomena including cell differentiation and maturation. these molecular events have not received proper attention during pituitary cell differentiation. the purpose of this study was to investigate glycoconjugate distribution on cell surface during adenohypophysis embryogenesis. material and methods: using lectin histochemistry, 5µm normalin fixed, paraffin embedded rat embryonic sections from day 10 to 20 of gestation (n=90) were incubated with different hrp-lectins from triticum vulgaris (wga) arachis hypogaea (pna) and griffonia simplicifolia (gsa1- b4) specific for terminal sugars sialic acid, n-acetyl galactosamine and ?-d- galactose ofcomplex glycoconjugates respectively. on the basis of intensity of staining that was determined by gong's method, sections were graded and non-parametric statistical test (kruskal wallis) was used to compare differences between samples. results: the results demonstrated that the reaction of adenohypophysis cells with wga started from gestational day13(e13) and increased with proceeding differentiation during the following days (p<0.05). a few cells reacted with pna from e13 and increased to e14 (p<0.05) and then identified to e17 and decreased afterward (p<0.05). gsa1-b4 didn't react with any cells during development. our findings also indicated that glycoconjugates with terminal sugars sialic acid and n-acetylgalactosamine may play a critical role in adenohypophysis development. conclusion: the appearance and changes of glycoconjugates on the cell surface with terminal sugars such as acid sialic and n-acetyl galactosamine may play a key role in tissue interactions and lead to developmental changes in certain embryoniorgans such as adenohypophysis