Ciccarelli C, Zani B M, Molinaro M, Grassi F, Eusebi F
Istituto di Istologia ed Embriologia generale, Università di Roma, Italy.
Naunyn Schmiedebergs Arch Pharmacol. 1988 Aug;338(2):121-4. doi: 10.1007/BF00174858.
Patch-clamp recordings were used to study the activation of ion channels in the cell membrane of cultured embryonic chick myotubes treated with the specific activator of protein kinase C, the phorbol ester 12-O-tetradecanoyl-phorbol-13-acetate (TPA; 1 x 10(-7) M). Myotubes exhibited a spontaneous channel activity when the TPA-induced dedifferentiative processes developed. This consisted in the activation of inward current channels (approximately 35 pS conductance; approximately 6 ms open time). These spontaneously active channels were insensitive to alpha-bungarotoxin, curare, atropine and tetrodotoxin and were not inhibited by the withdrawal of TPA. It is suggested that a prolonged stimulation of the protein kinase C causes a irreversible deregulation of the membrane channel function during cell dedifferentiation.
采用膜片钳记录技术研究用蛋白激酶C的特异性激活剂佛波酯12 - O - 十四酰佛波醇 - 13 - 乙酸酯（TPA；1×10⁻⁷ M）处理的培养鸡胚肌管细胞膜中离子通道的激活情况。当TPA诱导的去分化过程发展时，肌管表现出自发性通道活性。这包括内向电流通道的激活（电导约35 pS；开放时间约6毫秒）。这些自发激活的通道对α - 银环蛇毒素、箭毒、阿托品和河豚毒素不敏感，并且不受TPA撤除的抑制。提示蛋白激酶C的长期刺激在细胞去分化过程中导致膜通道功能的不可逆失调。
