| S1eep is one kind of physiologica1 process under themeticu1ous adjustment of centra1 nerve system, and is veryimportant to the maturity of deve1oping brain. Neuronsare high1y differentiated ce11s in vivo, owing specificmorpho1ogica1 structure and functions, and belonging topost--mitotic ce11s, means that neurons once formed in thedeve1oping course then can' t divided. So traditiona1neura1 regrowth is just l imited in nerve fiber, inc1udingaxon reprojection and synapse regrowth. In fact,scientists a1ways thought that mature brain neurona1ce11 s cou1d not regenerate when the brain fu1ly deve1opedthrough almost the whoIe twenty centure. 1n 1963, Altmanfirst reported that mature rats brain had new nellrons6$NX, (2oo2) ffR4$ktX ..tN99lkXk*B#8,..aA SCFmAN^ StaMffSlappeared. Then Anerican scholar Paton found positive newneurons in mature songbirds brain in l984. Especially inthe recent years scientists had some evidences showing newborn neurons in some brain areas of adu1ts, or having newborn neurons expressing products. This phenomenon can bedetected in some species from birds, rats and primates,therefore it induce chal1enge of traditiona1 theory ofembryo--derived neurogenesis. Hipoc8IIlPus possessesre1atively simp1e and high sequence sandWish,.,consanguineous corre1ation with senior functions of brainand s1eep--wake system, so is ideal model of brain research.The dentate gyrus of hippocanpus which takes on near1yrelation with spatial learning and memory, has amazingspecia1ity in that subgranu1e zone persist havingneuronal precursors, can pro1iferate and differentiate,produce new neurons. What's the regu1ating mechanism ofmature brain neurogenesis, where and when it wil1originate, what kinds cel1s of new borns and its functionnow is unknown, needs to try deep exp1oring. Stem ce11factor is a multipotent cytokine which is found in recentyears, fol1owing research in vitro and in vivo found thatSCF and its receptors have familiar regu1ation functionin mature brain with in embryo and developing period.$MX# (2bo2) ffR$$htet #$Nq9I&kK$4N8$$4tA SCF mANA $isMffSWhether s1eep deprivation cou1d induce neuronpro1iferation has not got definite conclusion so far. Inthe present research, we performed small pedestal s1eepdeprivation method to remove rapid eye movements1eep (REMS). We observed the neuron pro1iferation anddifferential in immunohistochemistry and doub1e 1abelingiariunohistochemistry staining, and the expression of stemce11 factor mRNA in situ hybridization technique afters1eep deprivation in rat hippocampus.EXPERIMENTAL PRECEDURESAnima1 treatmentsAdu1t ma1e Sprague Daw1ey rats (n=36, 200--300g, 50--65days o1d) were divided into three groups random1y j eachgroup had 12 rats ) they are: (l) rapid eye movements1eep deprivation group (or paradoxica1 s1eepdeprivation l PSD ) l sma11 pedesta1 diameter 7cm; (2)rapid eye movement sleep deprivation contro1 group,/sma11 pedesta1 diameter l3cm i (3) norma1 contro1 group.PSD mode1 derived of REMs, according to Cohen's smallpedesta1 s1eep deprivation method. Each rat wasdeprived of s1eep for 72 hours beginning at 8an ofexperimenta1 day. The normal contro1 rats stayed withintheir home cage throughout the experiment keeping their8$NX, (2002) ffR4$kte1 .ca#,lkXK*a"&,$.aR SCF ds^,taMffS,normal sleepwake cycle. Half animals were perfusedwith paraformaldehyte following normal serum after testinnnediatly, then removed the brain and fixed for 24 hourswith paraformaldehyte, paraffin sections were preparedat 3um, histochemical staining for counting ce11pro1iferating ratio and in situ hybridization forcalculating integra1 scores of stem cell factor InRNpositive signals. The other half animals are processedthe sane routine after three weeks, applying double1abeling inununohistochemical method to identify celltype of the new borns. All efforts were made to min...
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