Effects of cerebral lymphatic blockade on neural stem cell proliferation, differentiation and plasticity after subarachmod hemorrhage in rats

Abstract

Objective To investigate the effects of cerebral lymphatic drainage pathway on never stem cell proliferation, differentiation and plasticity after subarachniod hemorrhage （SAH） in rats. Methods An adult rat SAH model was induced by using the injection of fresh autologous arterial blood twice in cisterna magna, and a rat cerebral lymphatic blockade （CLB） model was made by ligation of the cervical lymphatic vessels and removal of cervical lymph nodes, Thirty rats were randomly divided into normal control, SAH and SAH ＋ CLB groups （n = 10 in each group）, the rats in each group were subgrouped into 3 days and 14 days subgroups （n = 5 in each subgroup）. 5-Bromodeoxyuridin （BrdU） was used to label the proliferation of neural stem cells （NSCs）. BrdU＋/glial fibrillary acidic protein （GFAP）＋, neurogenic differentiation （NeuroD） ＋ , and polysialic acid-neural cell adhesion molecule （PSA-NCAM） ＋ cells in cortex, hippocampus, and subventricular zone were detected by immunofluorescence double staining. Laser confocal microscopy was used to observe and count. Results BrdU＋ cells, NeuroD＋/BrdU＋ cells, GFAP ＋/BrdU＋ cells, and PSA-NCAM＋/BrdU＋ cells in the SAH group were increased in varying degrees compared to the normal control group （P 〈 0. 05 or 0.01 ）; BrdU ＋ cells and GFAP ＋/BrdU ＋ ceils were increased in the SAH ＋ CLB group compared to the SAH group （P 〈0. 05 or 0.01）, while NeuroD＋/BrdU＋ cells and PSA-NCAM＋/BrdU＋ cells were decreased significantly cornpared to the SAH group （P 〈 0.05 or 0.01）. Conclusions CLB may promote the proliferation of NSCs, but it is not conducive to NSCs differentiating into neurons and plasticity. Key words: Never stem cells; Subarachniod hemorrhage; Lymphatic vessels; Cell proliferation; Cell differentiation; Neuronal plasticity; Rats