Project/Area Number |
11694242
|
Research Category |
Grant-in-Aid for Scientific Research (B).
|
Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
神経・脳内生理学
|
Research Institution | Gunma University School of Medicine |
Principal Investigator |
KIDOKORO Yoshiaki Gunma University School of Medicine Institute for Behavioral Sciences, Division of Physiology Professor, 医学部, 教授 (00053083)
|
Co-Investigator(Kenkyū-buntansha) |
KUROMI Hiroshi Gunma University School of Medicine Institute for Behavioral Sciences, Division of Physiology Associate Professor, 医学部, 助教授 (30009633)
|
Project Period (FY) |
1999 – 2000
|
Project Status |
Completed (Fiscal Year 2000)
|
Budget Amount *help |
¥6,400,000 (Direct Cost: ¥6,400,000)
Fiscal Year 2000: ¥3,000,000 (Direct Cost: ¥3,000,000)
Fiscal Year 1999: ¥3,400,000 (Direct Cost: ¥3,400,000)
|
Keywords | Cultered neurons / Drosophila / mutants / synaptic transmission / shibire / neuromuscular junctions / vesicle recycling / synaptic vesicle pools |
Research Abstract |
i)Cultures of embryonic Drosophila neurons Eggs(3 to 4 hours after fertilization)were collected and sterilized with hypochlorate. The content was sucked into a glass pipette and transferred into Schneider's medium supplemented with fetal calf serum and insulin. Neurons send out processed within a few days and form contacts each other. Co-cultures with muscle cells are now being tried. ii)Size of vesicle pools, rates of mobilization, and recycling at neuromuscular synapses of a Drosophila mutant, shibire Two vesicle pools, readily releasable(RRP)and reserve(RP)pools, are present at Drosophila neuromuscular junctions. Using a temperature-sensitive mutant, shibir^<ets>, we studied pool sizes and vesicle mobilization rates. In shibire^<ts>, due to lack of endocytosis at nonpermissive temperatures, synaptic currents continuously declined during tetanic stimulation until they ceased as the result of vesicle depletion. By then, approximately 84,000 quanta were relased. Vesicles were mobilized from RP at a rate of 1/7-1/10 of RRP.Cytochalasin D inhibited mobilization of vesicles from RP, allowing us to estimate the size of RRP as 14%-19% of all vesicles. Vesicle recycling supports synaptic transmission during prolonged tetanic stimulation and the maximum recycling rate was 1000 vesicles/s.
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