東京大学大学院 農学生命科学研究科 獣医薬理学教室(堀教授)

獣医薬理学教室のDNA

獣医薬理学教室の研究テーマは「細胞情報伝達系の解明」で、平滑筋細胞を中心に、最近では免疫系細胞にも手を広げて展開しています。 この基盤は、1964年に American Journal of Physiology に発表された、以下の研究論文によって築かれました。

 

Am J Physiol 207: 873-876, 1964;

Ca45 uptake and tissue calcium in K-induced phasic and tonic contraction in taenia coli

N. Urakawa 1 and W. C. Holland 1

1 Department of Pharmacology, University of Mississippi School of Medicine, Jackson, Mississippi

High-K medium produces a tonic contraction in guinea pig taenia coli. If muscle strips are preincubated in glucose-free medium, K produces only a phasic contraction. A comparison of Ca45 entry and tissue Ca changes in the two responses were made. Both responses are accompanied by an enhanced uptake of Ca45. In addition to an increased Ca45 uptake, a significant rise of tissue Ca was observed during the tonic contraction. No detectable changes in tissue Ca were noted in the phasic contraction. In light of modern theories of muscle contraction, it was proposed that in the phasic contraction, sufficient Ca is released from a cellular site to initiate contraction, whereas in the tonic contraction enough Ca crosses the membrane to initiate contraction. The transmembrane Ca transport involved in the latter response appeared to be dependent on metabolism.

Key Words: Ca content of taenia coli : Ca45 uptake in taenia coli : cell permeability : taenia coli-Ca45 uptake and tissue Ca

Submitted on April 10, 1964