INVOLVEMENT OF PEDAL PEPTIDE IN LOCOMOTION IN APLYSIA - MODULATION OF FOOT MUSCLE CONTRACTIONS
INVOLVEMENT OF PEDAL PEPTIDE IN LOCOMOTION IN APLYSIA - MODULATION OF FOOT MUSCLE CONTRACTIONS
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DOI：
10.1002/neu.480210604
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发表时间：
1990-09-01
期刊：
影响因子：
--
通讯作者：
LLOYD, PE
中科院分区：
文献类型：
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作者：
HALL, JD;LLOYD, PE
足肽（Pep）是一种由15个氨基酸组成的神经肽，位于海兔中枢神经系统（CNS）内，主要分布在每个足神经节的宽带神经元上。通过细胞内染色和免疫细胞学或通过放射免疫测定法（RIA）从确定的神经元提取物来鉴定Pep-neurons。放射免疫分析表明，97%的所有Pep-like免疫反应（IR-Pep）在足神经被发现在三个神经支配的脚。几乎每一个Pep-neuron都会从这三条神经中的至少一条发出轴突。将Pep应用于足部肌肉导致由神经刺激或踏板运动神经元的细胞内刺激驱动的收缩的幅度和松弛速率增加。松弛速率的增加是主要效应。在“分裂足”制备中的细胞内记录揭示，Pep-neurons增加它们的整体放电率，并且在运动期间的每一步都以爆发的方式放电。足部神经刺激后，从足部灌注液中恢复的IR-Pep以频率依赖性方式增加。因此，似乎Pep-neurons的功能之一是在运动过程中调节足肌收缩性。
Pedal peptide (Pep) is a 15-amino-acid neuropeptide that is localized within the Aplysia central nervous system (CNS) predominantly to a broad band of neurons in each pedal ganglion. Pep-neurons were identified by intracellular staining and immunocytology or by radioimmunoassay (RIA) of extracts from identified nuerons. RIA reveals that 97% of all Pep-like immunoreactivity (IR-Pep) in pedal nerves is found in the three nerves that innervate the foot. Nearly every Pep-neuron sends an axon out at least one of these three nerves. Application of Pep to foot muscle causes an increase in the amplitude and relaxation rate of contractions driven by nerve stimulation or intracellular stimulation of pedal motor neurons. The increase in relaxation rate was the predominant effect. Intracellular recording in "split-foot" preparation reveals that Pep-neurons increase their overall firing rates and fire in bursts with each step during locomotion. Recovery of IR-Pep from foot perfusate following pedal nerve stimulation increases in a frequency-dependent fashion. Thus it appears that one function of Pep-neurons is to modulate foot muscle contractility during locomotion in Aplysia.