摘要
为研究环节动物的神经组织学特性 ,我们选择生活在我国的环节动物门典型代表参环毛蚓 (Pheretimaaspergillum)为研究对象 ,使用若干种兔抗鼠抗体 ,进行了免疫细胞化学与细胞化学染色 ,在光学显微镜下观察反应阳性细胞的形态与分布。研究发现 ,在参环毛蚓脑、咽下神经节、腹神经节所有神经细胞呈NSE阴性 ;在参环毛蚓脑 ,部分神经细胞呈NF2 0 0阳性 ,在咽下神经节、腹神经节未观察到NF2 0 0阳性神经细胞 ;在参环毛蚓脑观察到较多ED1阳性细胞 ;在参环毛蚓脑、咽下神经节、腹神经节均未观察到GFAP阳性细胞 ;在参环毛蚓脑未观察到NADPH d阳性神经细胞 ,而在咽下神经节和腹神经节部分神经细胞及纤维NADPH d阳性。结果表明 ,参环毛蚓神经细胞的神经细胞特异的烯醇化酶特性、神经微丝蛋白特性与星型胶质细胞的GFAP特性不同于哺乳动物 ;其神经组织存在有数量较多的吞噬功能的类似于哺乳动物小胶质细胞的细胞 ;参环毛蚓的脑不含有NO能神经细胞 ,而咽下神经节和腹神经节含有NO能神经细胞。
Despite the vast evolutionary gulf between Annelids and mammals their nervous tissues have retained considerable similarities in neuroendocrine function, for exemple, neurons that can secrete neuropeptide. However, the cytochemistry of nervous tissues including neurons and neuroglia is little known at present. Our experiment was undertaken to shed light on this area. Chinese earthworms, P.aspergillum were used as experimental animals. Worms were first fed with paper pulp and agar to cause them to excrete previously ingested earth and sand. They were then deeply anesthetized with 10% ethanol and dissected. The samples were fixed in fixative containing 4% paraformaldehyde and 2% picric acid in 0 01 mol/L PBS (pH 7 2) at 4℃ for 6 hours, transferred to 30% sucrose PBS until completely infiltrated, and then embedded in OCT compound (USA) before being quick frozen in liquid nitrogen and cut into 15 μm thick sections with a LEICA CM 1100 cryostat (Pharmacia). Sections were mounted on gelatin coated slides, preincubated in 0 01 mol/L PBS (pH 7 4) containing 0 25% Triton X 100 for 20 min then, in preparation for NADPH d histochemistry, transferred to a freshly prepared 0 05 mol/L Tris HCl(pH 8 0) containing 1 mg/mL nicotinamide adenine dinucleotide diaphorase (NADPH d) and 0 5 mg/mL Nitro Blue Tetrazolium (NBT). Sections were incubated at 37℃ for 1 hour, for immunocytochemistry. They were then stained with polyclonal antibodies against neuron specific enolase(NSE) and glial fibrillary acidic protein(GFAP), and monoclonal antibodies against neurofilament 200(NF200) and cytoplasmic antigen in bone marrow derived macrophages(ED1), and incubated at 37 ℃ for 1 hour and at 4℃ overnight. Sections were subsequently incubated in biotinylated goat anti rabbit IgG for 1 hour at 37℃ and in avidin biotin peroxidase complex for 2 hours at 37℃. Finally, they were reacted with diaminobenzidine (DAB) and 0 01% H 2O 2. Specific controls for the primary antiserum included the substitution of normal rabbit serum for the primary antiserum and omission of the primary antiserum, none of which showed any sign of immunocytochemical reaction. The consecutive sections were observed and the positive cells and fibers examined under a light microscope. Morphological measure were performed under 10×10 magnification. The positive cells of each antibody were counted respectively in the brain, subpharyngeal ganglion, ventral ganglion and enteric nervous system. NSE, GFAP and ED1 respectively are components of neurons, astrocytes and microglia in mammals. We found no NSE positive neurons in the brain, subpharyngeal ganglion or ventral ganglion, although some neurons, consisting primarily of small cells, were NF200 positive and others, comprised primarily of giant cells, were NF200 negative. There were no NF200 positive neurons in the subpharyngeal ganglion and ventral ganglion. Many ED1 positive cells were observed in brain. No GFAP positive cells were detected in the nervous system. NADPH d positive neurons existed in subpharyngeal ganglion and ventral ganglion, but brain neurons were NADPH d negative. These data indicate that the neurons of Annelids and mammals have different NSE immunocytochemical reactivity. There are no astrocytes containing GFAP, but there are many macrophages resembling mammalian microglia cells in the brains of Chinese earthworms, i.e., the astrocytes in the brain of the Chinese earthworm have a different GFAP cytochemistry to those of mammals but the cell like microglia in the brain of the Chinese earthworm share the same ED1 cytochemical characteristics as microglia in the brains of mammals. We conclude that:1. Morphologically, in the mammalian hypothalamus, neurosecretary cells include magnocellular neuroendocrine cells and parvocellular neuroendocrine cells. The parvocellular neuroendocrine cells are small metuliform, contain a typical nucleus like an eagles eye. The magnocellular neuroendocrine cells are fat, rounded, or ovoidal with a large acentric nucleus and clear nucleolus and are distrib
出处
《动物学报》
SCIE
CAS
CSCD
北大核心
2002年第6期777-782,共6页
ACTA ZOOLOGICA SINICA
基金
国家自然科学基金 (No 3 9770 3 83 )资助项目~~
