Co-Investigator(Kenkyū-buntansha) |
MIHARA Satoshi Kurume University School of Medicine Lecturer, 医学部, 講師 (40166103)
FURUKAWA Tetsushi Tokyo Medical and Dental University Medical Research Institute Instructor, 難治疾患研究所, 助手 (80251552)
TATSUMI Hitoshi Tokyo Medical and Dental University Medical Research Institute Instructor, 難治疾患研究所, 助手 (20171720)
HIRAI Kenji Tokyo Medical and Dental University Medical Research Institute Associate Profess, 難治疾患研究所, 助教授 (70156628)
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Research Abstract |
1.The small intestine isolated from adult guinea-pigs provoked perisitaltic movement. The ability of provoking peristalsis was preserved in the intestine from which both mucosa and submucosa were mechainically removed but which contained the myenteric plexus and two smooth muscle layrs (circular and longuitudinal) . It is speculated that the peristalsis is regulated by mechanisms organized within the enteric nervous system independent from the central nervous system. Thus, the intestine is provided with an intrinsic autonomic control system with regards to the intestinal movement. 2.Actions of neuropeptides, neuropeptide Y,substance P and neurokinin A,in the enteric nervous system were analyzed using various portions of the intestine, demonstrating the evidence of regional differences in the function of the enteric neurons. ATP and L-DOPA modulated transmitter release in the enteric nervous system. 3.A large amount of Ca influx activated Ca-binding of Ca-bindeing proteins, Ca extrusion to extracellular space, Ca uptake into Ca storage sites, and Ca pump. All of these are involved in maintaining the cellular Ca homeostasis. Na-K pump alpha3 isoform was found to localize both in nerve cells and in the heart excitation conducting system, suggesting the alpha3 isoform pump function is essential to the autonomous excitation of excitable cells. 4.Growth cones of cultured neurones isolated from the diagonal band of Broca of new born rats were observed using the video-enhanced differential interference contrast microscopy. Filopodia rapidly elongated at about 1mum/s from the growth cone in response to high potassium stimulation and retracted upon the end of stimulation. The tip of folopodia moved apparently in a Brownian manner. Before making a contact with other neighboring neurons, a transmitter substance, acetylcholin, was stored and even released in and from the growth cone. These processes are supposed to play an important role in organizing neural networks.
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