Harris-Warrick R M
Section of Neurobiology and Behavior, Cornell University, Ithaca, NY 14853.
Brain Res. 1989 Jun 5;489(1):59-66. doi: 10.1016/0006-8993(89)90008-5.
Forskolin decreases the transient potassium current, IA, in voltage-clamped somata of identified neurons in the stomatogastric ganglion of the spiny lobster, Panulirus interruptus. The diterpene reduces the peak outward current and accelerates the rate of inactivation of IA. Forskolin has no detectable effects on two other identifiable potassium currents in these cells, IK(Ca) and IK(V). Three identified stomatogastric neuron types (PD, PY, AB) have marked amounts of IA which are affected by forskolin; three other cell types (LP, IC, VD) have little or no IA, and forskolin has no effect on their outward currents. Bath application of 8-bromo-cAMP, N,N-dibutyryl-cAMP and IBMX do not affect IA. In addition, the forskolin analog, 1,9-dideoxyforskolin, which does not activate adenylate cyclase, mimics forskolin's effects on IA. Thus, the effects of forskolin on IA are not mediated by cAMP elevation.
福司可林可降低多棘龙虾（Panulirus interruptus）口胃神经节中已鉴定神经元的电压钳制胞体中的瞬时钾电流IA。这种二萜类化合物可降低外向电流峰值并加速IA的失活速率。福司可林对这些细胞中的另外两种可鉴定钾电流IK(Ca)和IK(V)没有可检测到的影响。三种已鉴定的口胃神经元类型（PD、PY、AB）具有大量受福司可林影响的IA；另外三种细胞类型（LP、IC、VD）几乎没有或没有IA，福司可林对它们的外向电流没有影响。浴用8-溴-cAMP、N,N-二丁酰-cAMP和异丁基甲基黄嘌呤不会影响IA。此外，不激活腺苷酸环化酶的福司可林类似物1,9-二脱氧福司可林模拟了福司可林对IA的作用。因此，福司可林对IA的作用不是由cAMP升高介导的。
