Objective The present study was aimed at investigating the effects of cholera toxin(CTx) on promoting the regeneration of retinal ganglion cells(RGCs) in hamster retina. Methods After optic nerve (ON) transection, an autologus sciatic nerve (attached graft, AG) was removed and sutured to the proximal stump of the ON. CT X was injected or (and) a small segment of sciatic nerve (SN) inserted intravitrously. Animals were separated into 5 groups:regenerating control group(AG groups and solution groups); AG+CT X groups; AG+SN groups; AG+CT X+SN groups; Effect and Dosage groups; Animals in the former 4 groups were allowed to survive for 2-6 weeks respectively. The regenerated RGCs were labeled retrogradely by granular blue, and the changes in number of regenerating RGCs in each retina were observed under fluorescent microscope. Results The mean numbers of regenerating RGCs in AG+CT X groups were increased and significantly higher than those in AG groups and solution groups at each time point( P

【Objective】 To examine the regeneration of NPY-immuno reactivity (IR) retinal ganglion cells (RGCs) and the effects of cholera toxin ( CTx) injected or/and peripheral nerve implanted on regeneration of NPY-IR RGCs. 【Methods】 16 adult golden hamsters were ramdomly divided into 4 groups. Optic nerve (ON) was transacted and a segment of autologous sciatic nerve (attached g raft, AG) was removed and sutured to the proximal stump of ON in regenerating co ntrol group (AG group). The animals in experimental groups were further treated with CTx injection or/and implantation of a short of segment sciatic nerve (SN) intravitrously. By using the retrograde labeling with fluorogold (FG) combined w ith fluorescent immunocytochemistry, the regenerated NPY-IR RGCs were observed and counted under fluorescent microscope. 【Results】 At 4 weeks after surgery, the mean number of regenerated NPY-IR RGCs per retina in AG group was 58±22 wh ich constitutes (3.36±0.65)% of the total regenerated RGCs. In AG+CTx, AG+SN and AG+CTx+SN experimental groups, the mean numbers of regenerated NPY-IR RGCs per retina were 143±47, 125±37 and 437±77 ordinally which constitute (5.15± 0.89)%, (5.34±0.37)% and (8.11±0.85)% of the total regenerated RGCs respec tively, which were increased significantly compared with those in AG group. 【Co nclusion】 The results show that the axotomized NPY-IR RGCs have th e capability of regenerating their axons into the attached PN graft, CTx and/or SN could enhance the regeneration of the NPY-IR RGCs.

The localization and development of substance P (SP) like immunoreactive retinal neurons in the adult, newborn and postnatal New Zealand albino rabbits were studied with immuaocytochemistry ABC method. We found most of the SPlike immunoreactive somas in adult rabbit retina located in inner margin of inner nuclear layer (INL) and ganglion cell layer (GCL). Their processes ramified in the lamina 1,3 and 5 of inner plexiform layer (IPL). Some immunoreaetive fibers in the layer of optic nerve fiber (LON) were occasionally observed. The highest cell density of SP-like somas occured in the visual streak (VS). The cell density gradually decreased from the VS to the ventral and dorsal periphery. In the new born rabbit retina, the labelled cell bodies and their processes appeared. Most of them located in the GCL, and a few of them located in the' INL. Their processes formed discontinuous layer in the lamina 5 and never seen in the lamina 3. The cell density of SP positive somas gradually increased from newborn to postnatal 4 th day. From postnatal 6 th day to 12 th day, the cell density gradually decreased. From postnatal 12 th day the somas mainly located in the INL. On the 20th day after birth the distribution and morphology of SP-like immunoreactive somas and processes had approached that of mature age. These results suggest that rabbit retinal SP-like immunoreactive neurons had appeared at prenatal period and continuously developed after birth.

Objective To investigate the effects of Colera Toxin(CTx) on the regeneration of retinal ganglion cells (RGCs) after distal axotomy in adult hamsters. Method After transecting the optic nerve(ON) intracranically,an autologus sciatic nerve (attached graft,AG) was removed and connected to the proximal stump of the ON.CTx was injected and/or a 2mm segment of sciatic nerve(SN) was inserted intravitreally.Animals were divideded into six groups:control group 1(AG group) and control group 2(solution group);AG+SN group;AG+CTx group;AG+SN+CTx group;effect and dosage group.Animals in the former five groups were allowed to survive for 4-6 weeks respectively.Granular blue fluorescent retrograde labeling method was used to measure the quantity of regenerating RGCs of control and experiment animals. Results The mean number of regenerating RGCs in AG+CTx groups were increased and significantly higher than those in control group 1 and control group 2 at each time point(P

Objective To investigate the differentiation of mesenchymal stem cells(rMSCs) of young rat into neuron-like cells with Ligustrazin hydrochloride. Methods rMSCs were separated from femurs marrow flushed out with DMEM(low glucose) by using a needle and syringe, then planted in plastic culture flask. Through expanded to 5 passages, rMSCs were induced to differentiate into neuron-like cells with Ligustrazin hydrochloride. Anti-neurofilament(NF-M), nestin, neuron-specific enolase(NSE), MAP-2,GAP-43 and glial fibrillary acidic protein(GFAP) antibodies were detected by immunohistochemistry. Results rMSCs were comprised a single phenotypic population and displayed a fibroblast-like morphology after 5 passage in culture. With 10*!?g/L bFGF pre-induce for 24*!h, then the medium was replaced with induction medium containing Ligustrazin hydrochloride. The induced-rMSCs exhibited neuronal morphological characteristics from the first half an hour to 5*!h. The neuron-like cells expressed NF-M, NSE, MAP-2,GAP-43 and nestin positive, but didn't express glial astrocyte marker GFAP.Conclusion rMSCs can be induced to differentiate into neuron like cells with Ligustrazin hydrochloride in vitro.

Objective To investigate the effects of transplantation of sciatic nerve(SN) and injection of 8-(4-Chlorophenylthio)-cAMP(CPT-cAMP) into the viteous on axotomized retinal ganglion cells(RGCs) in adult hamsters. Methods Twenty adult golden hamsters were ramdomly divided into 4 groups.Optic nerve(ON) was transected and a segment of autologous sciatic nerve(attached graft,AG) was removed and sutured to the proximal stump of ON in regenerating control group(AG group).The animals in experimental groups were further treated with CPT-cAMP injection and/or implantation of a short of segment sciatic nerve(SN) intravitrously.Fluorescent retrograde labeling method and quantitative anatomical techniques were used to measure the number of RGCs. Results 1.In control (AG) retinas,the mean number of regenerating RGCs was 1*!428?284/retina.2.In AG+SN group,the mean number of regenerating RGCs was 2*!220?415/retina.3.In AG+cAMP group,the mean number of regenerating RGCs was 2*!175?364/retina.4.The mean number of regenerating RGCs in AG+cAMP+SN group were 4*!255?820/retina.AG+SN,AG+cAMP groups were significantly different from AG group(P

Objective Use three inhibitors to block three different signaling pathway to explore the mechanisms of 3-isobutyl-1-methylxanthine(IBMX) and 8 (4 Chlorophenylthio) cAMP(CPT-cAMP) on the regeneration of retinal ganglion cells. Method Fluorescent retrogratde tracing method and quantitative anatomical techniques were used to measure the numbers of RGCs in control one,control two group and experiment groups. Results 1^ In control group 1(AG),the mean number of regenerating RGC was 1428??284/retina in 4 weeks after surgery; 2^ In control group 2(AG+IBMX+CPT-cAMP) the mean number of regenerating RGC was 4?917?1 489/retina in 4 weeks after surger; 3^ The mean number of regenerating RGC of experiment groups in 4 weeks after surgery were (1) H89 group(AG+IBMX+cAMP+H89):1?426?320/retina; (2)Wortmannin group(AG+IBMX+cAMP+Wortmannin):4143?1?057/retina; (3)PD98059 group(AG+IBMX+cAMP+PD98059):4?154?965/retina. Conclusion The promoting effects of IBMX and CPT-cAMP on regeneration of RGCs can be interrupted by H89 and can't be blocked by wortmannin and PD98059.

Objective To investigate the differentiation potenitial of ES cell derived epidermal like stem cells,to lay a base for the study of their differentiation mechanism,as well as seek new source to provide seed cells for skin engineering. Methods Mouse ES cells labeled or unlabeled by Hoechst 33342 were cocultrued with human amnion for 4 days.The epidermal like stem cell clones formed on the surface of amnion were digested with trypsin and transplanted into hypodermis of nude mice for 10,20 and 45 days,then the differentiation pattern of the donor cells were observed and estimated with morphological and immunohistochemical method. Results The grafts may differentiate into tubular or follicular like structures lined with simple or stratified epithelial like cells which expressed ? 1 integin,CK19,CK15,PK involucrin and CEA respectively after 10 to 30 days of transplantation.Keratinized stratified squamous epithelium,sebaceous gland like,sweat gland like and hair follicle like structures were observed after 45 days ofter transplantation.Conclusion ES cell derived epidermal like cells might have differentation potential to diffreentiate into keratinized stratified squamous epithelium,sebaceous like,sweat gland like and hair follicle like structures.

Objective The present study was aimed at investigating the regeneration promoting mechanism of forskolin and IBMX on injured retinal ganglion cells(RGCs). Methods Fluorescent retrograde labeling and autologus sciatic nerve transplanting techniques were used to observe the effects of H 89 or/and wortmannin on the regeneration promoting effects of forskolin and IBMX on injured retinal ganglion cells by intravitreal injection. Results Both H 89 and wortmannin could partly block the promoting effects of forskolin and IBMX on regeneration of injured RGCs, the effects of wortmannin might be more powerful, if united, they could inhibit the effects of forskolin and IBMX completely.Conclusion The regeneration promoting effects of forskolin and IBMX on injured RGCs might be realized by PKA CREB and PI3 K Akt accesses.

Immunohistochemistry was utilized to investigate the light and electron micros-copic localization of neurotensin-like (NT) immunoreactive amacrine cells in thechicken retina.The results showed that the NT-immunoreactive cell bodies wereoval and situated in either the second or third row of cells from the inner borderof the inner nuclear layer.The processes of such cells extended into the innerplexiform layer where they ramified as a fine plexus in sublamina 1 and as a denseplexus in sublamina 3 and 4.At the ultrastructural level,NT positive soma exhibited a rather dense and evenlydistributed immune reaction product throughout their cytoplasm.The nucleus ofNT-amacrine cells possessed a round,unindented nuclear membrane.NT positiveprocesses of such cells receive synaptic input from processes of unlabeled amacrineand bipolar cells.They formed synaptic output onto processes of nonimmuno-reactive amacrine cells and bipolar cells.Moreover,each of the above synapticrelationships were identified in each of sublamina 1 and 3 to 4 of the inner plexiform layer.In addition,NT positive processes fromed synaptic output to processesdevoid of synaptic vesicles,which may originated from ganglion cells.They alsoformed synaptic output to somas situated in the innermost cell row of the innernuclear layer.Identification of synaptic elements and retinal circuitry were also discussed.