1.Effects of Nocodazole on Protein Synthesis Appratus of Tumor Cells.
Sun Hee KIM ; Joo Young KIM ; Eon Gee SUNG ; Yun Chanl LEE
Korean Journal of Anatomy 1997;30(3):243-258
Nocodazole is an anticancer agent that acts on microtubules or filaments. HeLa, Hep G2, A549, L929 and NIH/3T3 cell lines were cultivated in alpha-MEM with 3micrometer or 30micrometer nocodazole. To elucidate the associations between nocodazole`s antitumor actions and these effects, the influences of nocodazole on the cellular morphology and the organelles involving synthesis, secretion and destruction of proteins were investigated under light and electron microscopes. The changes of intermediate filaments such as pancytokeratins and vimentins that maybe suggest antimetastatic action of nocodazole were observed using immunocytochemical technique, PAP at light microscopic level. Rounded or micronucleate cells were induced by treatment with 3micrometer and 30micrometer nocodazole for 2 hours to 4 days. Multimicronucleate cells appeared in experimental groups of all cell lines. Nuclear foldings occurred in cells of experimental groups treated with nocodazole for 2-3 days. The numerical increases of rough endoplasmic reticulum were observed in HeLa cells treated with nocodazole for 3 days and the dilatation or numerical increases in L929 cells treated with nofodazole for 1-3 days. The fragmentations or dispersion of Golgi complex were observed in cells treated with nocodazole for 1-3 days. The amount of filaments increased in cells treated with nocodazole for 1-3 days. The number of lysosomes increased in cells treated with nocodazole for 1-3 days. The number of liposomes also increased in Hep G2 cells treated with 30micrometer nocodazole for 3 days and in 3micrometer & 30micrometer, 3 days group of 3T3 cells. The amount of pancytokeratins and vimentins increased in cells treated with nocodazole for 1-3 days. Taken together, depolymerization of microlubules was induced by nocodazole, and then the organization of cells was disintegrated. As a result, the rounded cells, the cells having multimicronuclei, and the changes of golgi complexes occurred. But there were relatively no great changes of rough endoplasmic reticulum. The amount of intermediate filaments that maintain the differentiated states of cells increased by nocodazole treatment. It was suggested that morphological changes of cells could be used in evaluation of actions of nocodazole. Especially, the increase of amount of intermediate filaments by nocodazole changed cells of each cell line from undifferentiated state to differentiated, and therefore the author hope that the changes in amount of intermediate filaments provide an important clue in anticancer and antimetastatic actions of nocodazole.
3T3 Cells
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Animals
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Cell Line
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Dilatation
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Endoplasmic Reticulum, Rough
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Golgi Apparatus
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HeLa Cells
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Hep G2 Cells
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Hope
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Humans
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Intermediate Filaments
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Liposomes
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Lysosomes
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Mice
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Microtubules
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Nocodazole*
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Organelles
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Vimentin
2.Effect of carbamazepine on tetrodotoxin-resistant Na⁺ channels in trigeminal ganglion neurons innervating to the dura.
Jin Eon HAN ; Jin Hwa CHO ; Michiko NAKAMURA ; Maan Gee LEE ; Il Sung JANG
The Korean Journal of Physiology and Pharmacology 2018;22(6):649-660
Migraine is a neurological disorder characterized by recurrent and disabling severe headaches. Although several anticonvulsant drugs that block voltage-dependent Na⁺ channels are widely used for migraine, far less is known about the therapeutic actions of carbamazepine on migraine. In the present study, therefore, we characterized the effects of carbamazepine on tetrodotoxin-resistant (TTX-R) Na⁺ channels in acutely isolated rat dural afferent neurons, which were identified by the fluorescent dye DiI. The TTX-R Na⁺ currents were measured in medium-sized DiIpositive neurons using the whole-cell patch clamp technique in the voltage-clamp mode. While carbamazepine had little effect on the peak amplitude of transient Na⁺ currents, it strongly inhibited steady-state currents of transient as well as persistent Na⁺ currents in a concentration-dependent manner. Carbamazepine had only minor effects on the voltage-activation relationship, the voltage-inactivation relationship, and the use-dependent inhibition of TTX-R Na⁺ channels. However, carbamazepine changed the inactivation kinetics of TTX-R Na⁺ channels, significantly accelerating the development of inactivation and delaying the recovery from inactivation. In the current-clamp mode, carbamazepine decreased the number of action potentials without changing the action potential threshold. Given that the sensitization of dural afferent neurons by inflammatory mediators triggers acute migraine headaches and that inflammatory mediators potentiate TTX-R Na⁺ currents, the present results suggest that carbamazepine may be useful for the treatment of migraine headaches.
Action Potentials
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Animals
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Anticonvulsants
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Carbamazepine*
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Headache
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Kinetics
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Migraine Disorders
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Nervous System Diseases
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Neurons*
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Neurons, Afferent
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Rats
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Sodium Channels
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Trigeminal Ganglion*