周氏新对虾有髓鞘神经纤维的超微结构

Study on the ultrastructure of the myelinated nerve fiber of the shrimp, Metapenaeus joyneri

周氏新对虾 (Metapenaeusjoyneri)的有髓鞘神经纤维为椭圆型、圆型 ,椭圆型长轴直径 4 0～ 6 5 μm ,短轴直径 18～ 2 5 μm .轴突直径 6～ 10 μm ,位于髓鞘的一侧 ,轴突壁由微管组成 .在轴突壁与膜层之间存在液体间隙 .在液体间隙外的髓鞘厚约 1μm ,由 3层膜层和 2层微管层组成 ,在部分髓鞘的结构中 ,微管层增厚 .在髓鞘结构中观察到高嗜锇性区域 。

Myelinated nerve fiber of shrimp, Metapenaeus joynery ,ellipse or spherical,were about 40～65 μm in diameter of long axis and about 18～25 μm in diameter of short axis. Axons were about 6～10 μm in diameter.The walls were made of microtubes. There was a liquid space between the axon walls and the membrances. The sheath of nerve fiber,which was made of three membrance layers and two microtube layers, outside axon walls measured was 1μm. There were more microtube layers in the part of the sheaths. High osmiophil lamellae, which were composed of the electron_dense and electron_light membrance layers, were found in the sheaths.