ABSTRACT
Objective To observe the expression of heparan sulfate proteoglycan(HSPG)-Agrin in rat cortex of postnatal time in order to understand the relation between the development of cortex and agrin. Methods We performed immunohistochemical analysis of agrin expression in the postnatal rat cortex with agrin-specific polyclonal antibody. Results Agrin expression was shown to have significant differences in the different periods of postnatal time.It increased from postnatal 2 day(p2) to postnatal day 6(p6),then declined steadily after p6 and reached adult levels by 4w.In this periold of time,agrin has different expression peak following to the cortex layer development.Conclusion:Agrin is related to the development of cortex and may play an important role in the developing of central nervous system.;
ABSTRACT
Objective In order to investigate the roles of hIGF\|1 in treatment of diabetes mellitus and diabetic syndromes,the gene of human insulin like growth factor type Ⅰ(IGF\|1) was cloned and constructed into eukaryotic expression vector,then the expression and activity were determined. Methods Total cellular RNA of human fetal liver was abstracted and the RT\|PCR amplification of the cDNA fragment was performed.The fragment was cloned into pUCM\|T vector and sequenced.The eukaryiotic expression vector was recombined and transfected into fibroblast cell line,COS\|7.The expression of hIGF\|1 was examined by in situ hybridization and immunohistochemistry.The effect of hIGF\|1 on cultured islet cells was observed by glucose\|stimulated insulin release assay. Results The cDNA fragment of 710bp with additional Kozak sequence was amplified by RT\|PCR.Eukaryiotic expression vector pCI\|neo/hIGF\|1 was constructed and IGF\|1 gene expressed in COS\|7.The biological activity of hIGF\|1 was proved by increasing inslin secretion from islet cells.Conclusion\ The newly constructed vector,pCI\|neo/hIGF\|1 could be transfected into COS7 cells and its expressed product showed to have the biology activity of hIGF\|1.\;[
ABSTRACT
Objective In order to investigate the effect of nutrition and induction of Sertoli cell on cultured neural stem cells(NSCs) from embryonic mesemcephalon in the rat. Methods Sertoli cells from the testis and the neural precursors(NPs) from the ventral mesencephalon in embryonic SD rat(E13) were co-cultured.The detections of immunoreactivities of nestin,?-Ⅲ tubulin and tyrosine hydroxylase(TH) were made by immunocytochemistry after 5, 7, 10 and 14 days in vitro. Results The number of NPs with nestin-positive was decreasing along the time of the co-culture,while the ?-Ⅲ tubulin-positive cells and TH-positive cells were increasing.The number of ?-Ⅲ tubulin-positive cells was quite high at the 7th day and the TH-positive cells were at the highest level at the 10th day in vitro.At any stage,the numbers of TH-positive cells were higher in the co-culture,compared with those in the mono-culture.Conclusion The neural precursors from the ventral mesencephalon in embryonic rat can be directly induced to differentiate into the dopaminergic progenitors by co-cultured with the Sertoli cells.