ABSTRACT
Objective To study the estradiolNGF regulatory cascade in retinal endothelial cells. Methods Retinachoroids vascular endothelial cell line RF/6A from rhesus was cultured in M199 medium contain 20% FBS.mRNA of ER,NGF and its receptors,TrkA and P75 NTR were detected with RTPCR.The cells were incubated with NGF,VEGF,antibodies against NGF or VEGF,and K252a(100nmol/L),the specific inhibitor of TrkA,separately or in different combination.MTT based cell counting assay was used to study the viability of the cells.The apoptosis was evaluated by FACS,mass migration by wound healing assay,and tubogenesis by AngioMatrix assay. Results We amplified the specific fragments of cDNA of ER,NGF and NGF receptor TrkA using RTPCR.10?nmol/L1??mol/L estradiol augments the proliferation and increases the viability of RF/6A in a dosage dependent manner.In the wound healing based migration assay,we found the similar alteration.This effects of estradiol was partially blocked by NGF neutralized antibody and K252a.Apoptosis rates were at the similar level among the groups.For the tubogenesis of RF/6A,we found no augmentation by NGF,and no blocked augmentation by estradiol.Conclusion NGF,first identified as the survival factor of nerve system,now also seemed to be an activator of retinal endothelial cell,is under the regulation of estrogen.The proliferation and migration,but not the tubogenesis of retinal endothelial cells are regulated by this regulatory cascade.
ABSTRACT
Purpose The regeneration effects of nerve growth factor(NGF)on superior cervical ganglia innewborn mice destroyed by vincristine(VCR)and peroneal nerve of adult rats destroyed by grip were studiedby morphological methods. Methods Superior cervical ganglia. The Qunming newborn mice at 2 dayswere divided into 3 groups: experiment, control and blank. The experiment animals were injected with VCR,10 μl/g of body weight at a concentration of 0.02 mmol/L. Simultaneously, the NGF was injected 2,5,10μg/g of body weight, respectively. But the control animals were only injected with VCR at the same dose.The blank control animals weren' t treated anything. All of these chemicals were injected once a day for 4days. 24h after the last injection, the superior cervical ganglia were dissected out and analyzed their size andmorphology. Peripheral nerve. The peroneal nerve of SD adult rats were destroyed by grip, and divided into2 groups: experiment and control. The experiment rats were injected with NGF 2,4 and 8 μg/kg of bodyweight respectively, near the gripped nerve,once a day for 12 days after 24 h of the injury. 24 h after the lastinjection, the perone al nerve and extensor longus digitorum were dissected out and analyzed their morphologyand counted the number of nerve fiber at proximal and distal injury. Results VCR injection in newbommice produced severe atrophy of superior cervical ganglia. And the neuronal cells apoptosed and decomposed.Simultaneous injections of NGF prevented the noxious effects of VCR, and resulted in an increase intransverse diameter from 61 to 95 percent and the total number of neuronal cells from 59 to 70 percent. Thisimproved degree was related to the dose of NGF. Furthermore, NGF obviously improved the structure of peroneal nerve and extensor longus digitorum. And this effect was the best in the high dosage. ConclusionsNerve growth factor has an obvious regeneration effects in superior cervical ganglia of newborn mice destroyed by VCR and peroneal nerve of rat destroyed by grip.
ABSTRACT
Objective The purpose of this experiment is to study the in vivo differentiation and myelin formation of rat striatal neural precursor cells after transplantation into homogeneous retina,observe the order of myelination and its influence on the structure of retina,establish an animal model of CNS myelin formation in vivo. Methods Passage cultured striatal neural precursor cells from embryonic Sprague-Dawley rats were transplanted into the vitreous cavity of neonatal rats.In different stages after transplantion,myelin formation in retina was observed under light and electron microscope and analysed with different stained methods.Results Bundles of myelin appeared in parts of retina 4 weeks later.The distribution and morphology of myelined area expanded with prolonged survival time after cell transplantation.Oligodendrocyte wrapped the naked axons and formed normal myelin limited in the nerve fiber layer.Myelination influenced the distribution of local retinal ganglion cells.Conclusion Striatal neural precursor cells could differentiate into oligodendrocytes and formed myelin after transplanted into retina and the naked axons in retina promoted the myelin formation.This model provides a new method to study the myelin formation and myelin-axon interaction in vivo.