Studies Of The Relations Between The Marginal Division And Limbic System,and The Effects Of Hypoxia On The Marginal Division In Rats

Purposes and meaning The "marginal division"(MrD) is a new subterritory of striatum firstly discovered by Siyun Shu in 1988 and was studied for several years by a lot of researchers. MrD located between caudate putanien and globys pallidus, and forms a flat, pan-shaped zone .It is readily distinguishable from the rest of striaturn by consisting of spindle-shaped neurons, special connections, and intensely expressed immunorectivities of many neuropeptides and some monoamines in the fibers, terminals and neuronal somata. Studies in the past years shoved that MrD exists fiber connection with the reticular part of substantia nigra, the medial part of globys pallidus, Meynert's basal nucleus and interior nucleus of posterior plate in tbalamus. It also showed possessed some functions of limbic system, such as learning and memory. Global ischemia can induce the malfunction of learning and the change of some neurotransmitters immunoreaction in rats. Whether or not the MrD, as a part, belongs to lixnbic system is short of the evidence up to now. What is the main fact to affect the changes of MrD still need to be confirmed. Although the studies showed a malfuncton of learning in the MrD-lesioned rats and a c-fos expression in hippocaxnpus following kainic acid stimulation, the most important indicator-long term potentiation(LTP) was still not be obsemed. Therefore, in this research, it put the stress on the study of the transcription and expression of the limbic marker protein-limbic system-associate membrane protein(LAMP)in MrD, the study of neurotransmitters change following hypoxia in MrD, and the study of hippocanipal LTP in the MrD- lesioned rats. The finding in the present study will give further formation about the questions mentioned above. Methods and result Part one: 1.. The transcription of LAMP mRNA in MrD. 12 adult male Sprague-Dawley rats( I 80-20g) were deeply anesthetized with chloral hydrate. The rat re transcardially perfused with ice-cold paraformaldehyde in sodiumborate buffer after a brief saline rinse, thirty-micrometer-thick frozen sections were collected in 0.01 M phosphate-buffered saline in I%0DEPC solution. The distribution of the LAMP transcript in the adult rat brain was determined by using in situ hybridization. The situ hybridization probes, a 53- mer oligonucleotide derived from the eDNA LAMP sequence (nucleotides 918-970) was synthesized(Shanghai biochemisty institute).The probes was labeled with digoxingemn in our laboratory. A differential distribution of LAMP was apparent throughout the cerebral cortex, with the most heavy labeling seen in silo- and mesocortial areas. Among these regions, transcript expression in the hippocanipus was intense, especially in all fields of Ammon's horn. There was a heterogenous distribution of LAMP in the dentate gyrus, with transcript expression intense ventrally, but only moderate dorsally. A dorsoventral gradient of LAMP expression was seen in the striatum with the dorsal, caudate-putamen sparsely labeled and the ventral striatum(nucleus accwnbens) and ventral pallidum moderately labelled. MrD was one of the most heavy labelled area, the intense level of LAMP transcript expression was same as hippocampus and heavier than caudate-putamen or pallidum. The positive transcript neurons colored with royal blue granules and the positive somata were mosty fusiform in shape, with their long axes running parallel to the border between the striatum and the globus pallidus. 2.The protein...