運動神経末端からのハイポスモティック神経分泌は,カルシウムに依存するプロセスですか?
Y Shimoni1, E Alnaes, R Rahamimoff
1Department of Physiology, Hebrew University-Hadassah Medical School, Jerusalem, Israel.
Nature
|May 12, 1977
まとめ
細胞外液のオスモラリティが上昇すると,神経末端から神経伝達物質の放出が著しく増加します. この超オスモティック神経分泌は,細胞内カルシウム濃度に依存し,神経信号伝達に影響を及ぼします.
科学分野:
- 神経科学は神経科学である.
- 細胞生物学 細胞生物学
- 生理学 生理学とは
背景:
- 自発的な神経伝達物質の放出は,細胞外液のオスモティック圧力によって調節されます.
- ハイパーオスモティック状態 (20〜30%のオスモラリティの増加) は,運動神経末端から神経伝達物質の放出を促進します.
- ハイポロスモティック神経分泌のメカニズムとそのカルシウムへの依存性は,完全に理解されていません.
研究 の 目的:
- 細胞内カルシウム濃度 ([Ca]in) がハイパーオスモティック神経分泌における役割を調査する.
- 増加した[Ca]inがハイパーオスモティック神経分泌を引き起こすという仮説を検証するために.
- の神経筋シナプスで[Ca]inを間接的に評価する.
主な方法:
- の神経筋シナプスにおける細胞内カルシウム濃度 ([Ca]in) を推定するために,間接的な技術を使用した.
- 想定されたミニチュアエンドプレートポテンシャル (m.e.p.p.) 周波数は[Ca]in.を反映しています.
- 変異したカルシウム伝導度 (g ((Ca)) と電気化学的梯度が,ハイポロスモティック神経分泌に与える影響を調べました.
主要な成果:
- ハイパロスモティック神経分泌は,細胞内カルシウム濃度 ([Ca]in) に依存することが判明しました.
- この研究は,増加した[Ca]inと,ハイパーオスモティックな条件下で神経伝達物質の放出が強化された関係を示す証拠を提供します.
- 間接的な測定では,m.e.p.p.p.との相関が示唆されている. 周波数と[Ca]イン.
結論:
- ハイパロスモティック神経分泌は,細胞内カルシウム濃度 ([Ca]in) に依存しています.
- この発見は,高濃度の[Ca]インが,神経伝達物質の放出に対するハイパロスモティックストレスの影響を媒介するという仮説を裏付けている.
- この研究は,シナプス伝送の調節の理解に貢献します.
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