Bhave S V, Malhotra R K, Wakade T D, Wakade A R
Department of Pharmacology, School of Medicine, Wayne State University, Detroit, MI 48201.
J Neurochem. 1990 Feb;54(2):627-32. doi: 10.1111/j.1471-4159.1990.tb01917.x.
Sensory neurons of the chick embryo are supported in culture by several neurotrophic factors, including the phorbol esters. Because phorbol esters are known to activate one of the second messengers, namely, protein kinase C, it was of interest to see if the neurotrophic action of phorbol 12,13-dibutyrate (PDB) was related to the activation of protein kinase C in sensory neurons. Sensory neurons were obtained from dorsal root ganglia of 10-day-old chick embryos and maintained in a serum-free medium for several days to quantify survival and analyze protein kinase C activity. PDB (30 nM) supported the survival of approximately 50% of the total number of neurons plated. This value was comparable to that supported by nerve growth factor (NGF; 40 ng/ml). If PDB and NGF were added together, there was no additive effect on the survival. The protein kinase C activity of the particulate and cytosolic fractions of sensory neurons supported by NGF for 3 days was 1.26 +/- 0.1 and 2.9 +/- 0.32 pmol/min/mg of protein, respectively. In contrast, neurons supported by PDB showed an approximately 500% increase in enzyme activity in their particulate fraction. The enzyme activity of the cytosolic fraction was decreased by approximately 40%. If NGF-supported neurons were treated with PDB (30 nM) for 15 min, protein kinase C activity increased greater than 400% in the particulate fraction, whereas an approximately 50% decrease was observed in the cytosolic fraction. The protein kinase C value, expressed as a ratio of the activities in the particulate to cytosol fractions, showed large increases after phorbol treatment.(ABSTRACT TRUNCATED AT 250 WORDS)
鸡胚感觉神经元在培养中受到多种神经营养因子的支持，包括佛波酯。由于已知佛波酯可激活一种第二信使，即蛋白激酶C，因此研究佛波醇12,13 - 二丁酸酯（PDB）的神经营养作用是否与感觉神经元中蛋白激酶C的激活有关就很有意义。感觉神经元取自10日龄鸡胚的背根神经节，并在无血清培养基中培养数天，以量化存活情况并分析蛋白激酶C的活性。PDB（30 nM）支持了所接种神经元总数约50%的存活。该值与神经生长因子（NGF；40 ng/ml）所支持的值相当。如果将PDB和NGF一起添加，对存活没有相加效应。由NGF支持3天的感觉神经元的颗粒部分和胞质部分的蛋白激酶C活性分别为1.26±0.1和2.9±0.32 pmol/分钟/毫克蛋白。相比之下，由PDB支持的神经元其颗粒部分的酶活性增加了约500%。胞质部分的酶活性降低了约40%。如果用PDB（30 nM）处理由NGF支持的神经元15分钟，颗粒部分的蛋白激酶C活性增加超过400%，而胞质部分则观察到约50%的降低。以颗粒部分与胞质部分活性之比表示的蛋白激酶C值在佛波醇处理后大幅增加。（摘要截断于250字）
