• Development and Reproduction
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• v.8 no.1
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• pp.43-47
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• 2004

The present paper studied neurosecretory cell types and their seasonal secretory activity in the eyestalk of Palaemon macrodactylus. The samples were monthly collected in Nakdong estuary for one year. The eyestalk consisted of lamina ganglionaris, medulla externa medulla interna, and medulla terminaris. four types of neurosecretory, A-, B-, C- and D-cells are found in the eyestalk. The A-cells are located in the medulla externs. Althoush the B- and C-cells are located in the medulla interna and medulla terminalis, B-cells are predominant in medulla interna and C-cells are usually distributed in medulla terminaris. The size of D-cells are larger than other types of cells in size. The neurosecretory cells except D-cells show a remarkable change with month. The A-, B-, and C-cells are activated from March and April to July, and decreased at August.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.24 no.5
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• pp.327-339
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• 1991

The present paper is a histological study of neurosecretory cells in the brain and the thoracic ganglion with the gonadal development in Palaemon serrifer. The reproductive cycle includes the successive stages of the growing period (February-March), the mature period(April-May), the ripe and spent periods(June-August) and the degenerative and resting periods(September-January). The neurosecretory cells are grouped into four types based on Matsumoto(1958) : A-,A'-, B- and E-cells. A- and A'-cells are $80-90{\mu}m,\;B-cell\;is\;30-40{\mu}m$ and E-cell is $10-15{\mu}m$. A- and B-cells are the positive to CHP and AF, while B-cell is the positive only to AF. The secretory grannules of a A-cell are transported to the axon, and at the same time they are discharged through the peripheral membrane. Of the four neurosecretory cells, A- and I-cells show the difference of secretory activity according to the gonad developmental process. In the female, A-cells show secretory activity for the ripe and spent periods, while I-cells show for the mature, ripe and spent periods. In the male, A-cells show secretory activity for the mature, ripe and spent periods, while I-cells show for the growing, mature, ripe and spent periods.

• Applied Microscopy
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• v.12 no.2
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• pp.55-68
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• 1982

The study on the nerve cells in the pars intercerebralis(IP) of 5-day-old cabbage butterfly Pieris rapae L. was performed to observe their ultrastructures and classify them on the basis. of the differences in size, shape and relative distribution cf cell organelles. The brain-subesophageal ganglion complex was fixed in 1% paraformaldehyde-1% gluaraldehyde mixture and embedded in araldite mixture. The transverse thin sections of IP were stained with uranyl acetate and lead citrate and examined by Hitachi 500 and ]EM 100B electron microscope. Five distinct types. of nerve cells are recognized and are arbitrarily designated as Type I, Type II Type III, Type IV and Type V. Type I neurone: These neurones are neurosecretory cells. Several neurosecretory cells are. recognized in the pars intercerebralis. They are roughly round or peach-shaped cells measuring $13{\sim}25{\mu}m$ in diameter. The rounded nucleus shows about $5{\sim}10{\mu}m$ in diameter. The chromatin is predominantly diffused with only occasional dense patches. The perikaryon contains numerous. mitochondria, free polyribosomes and neurosecretory granules. The neurosecretory granules are relatively uniform in electron density, and each one is about $100{\sim}400{\mu}m$ in diameter and surrounded by a single membrane. The granules are also observed mostly as in groups. In one group of neurones the cisternae of endoplasmic reticulum are distended or in other group of neurones are not distended. Golgi saccules are slightly dilated at their lateral extremities and contains. frequenty dense rounded materials. Type II neurone: Thes have the largest soma in the pars intercerebralis about $30{\sim}35{\mu}m$ in diameter. They also show roughly polygonal in shape. The nucleus is elongated or sickle-shaped. The chromatin is mainly in the euchromatin form. The perikarya in these cells are well populated with populated with free ribosomes and contain numerous mitochondria and Golgi bodies. The cisternae of granular endoplasmic reticulum are also well distributed. Type III neurone: They are oval or spindle-shaped and also medium-sized. neurones approximately $15{\sim}17{\mu}m$ in length. The nucleus is oval or slightly elongated in shape and $8{\sim}9{\mu}m$ in length. The chromatin occurs in diffused form. The cytoplasm contains many filamentous or oval mitochondria. The perikaryon has also numerous free polyribosomes and cisternae of granular endoplasmic reticulum. Type VI neurone: They are roughly polygonal in shape probably due to the close approximation of the adjacent cells. The soma is about $7{\sim}8{\mu}m$ in diameter. The nucleus is round or oval in shape and $5.0{\sim}5.8{\mu}m$ in diameter. The necleus also occupies a large proprion of the cell body. The perikaryon is well populated with free ribosomes and contains several mitochondria and cistenae of granular endoplasmic reticulum. Type V neurone: These neurones are similar to Type VI neurones in various respects such as cell size and cell inclusion, but they differ from Type IV neurones in shape. The soma is oval or slightly elongated. The cell body contains several filamentous and oval mitochondria.