• Toxicological Research
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• v.3 no.2
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• pp.73-80
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• 1987

Primary cultures of adult rat hepatocytes were used to study the cytotoxicity of D-galactosamine. Hepatocytes were isolated by a collagenase perfusion technique and maintained as monolayers in serum-free medium on collagen-coated culture dishes. Treatment of galactosamine to the culture markedly inhibited the uptake of ${\alpha}$-aminoisobutyric acid (AIB) inducible with glucagon and dexamethasone. At0.1 mM of galactosamine, AIB uptake was inhibited significantly when treated for 12 hr. At higher doses (0.25, 0.5 and 1.0mM), a significant inhibition was noticed after 1 hr exposure. Generally the magnitude of the inhibition was related to the dose and treatment time of galactosamine. Treatment of galactosamine also produced a dose- and treatment time-related suppression of the tyrosine aminotransferase (TAT) induction caused by dexamethasone. Meanwhile, uptake of ouabain was not affected by the treatment of galactosamine. The viability of the hepatocytes was decreased only slightly by the treatment of galactosamine; more than 87% of the cells excluded tryphane blue when treated 1 mM galactosamine for 12 hr. Galactosamine induced depressions of AIB uptake and TAT activity were prevented by the simultaneous addition of uridine to the culture. D-Galactosamine, cytotoxicity, hepatocytes culture, ${\alpha}$-aminoisobutyric acid uptake, tyrosine aminotransferase.

• Asian-Australasian Journal of Animal Sciences
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• v.3 no.2
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• pp.91-96
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• 1990

This experiment was designed to determine whether ${\alpha}$-aminoisobutyric acid (AIB) can be used to predict membrane function of spermatozoa by measuring the uptake of AIB by fresh, stored and frozen-thawed rooster spermatozoa. When spermatozoa were stored at low temperature ($0{\sim}3^{\circ}C$) for 24 h. no difference was found in AIB uptake compared with fresh spermatozoa, whereas storage for 48 h resulted in a slight increase in AIB uptake by spermatozoa. On the one hand, the uptake of AIB by frozen-thawed spermatozoa was less than that by fresh spermatozoa. This suggests possibility of a different membrane transport system between spermatozoa preserved at low temperature ($0{\sim}3^{\circ}C$) and those frozen-thawed. Glycerol used as cryoprotectant may modify rooster sperm membrane in a different manner from cold preservation. Ouabaine ($10^{-4}M$) caused a slight decrease in AIB uptake, but caffeine ($10^{-2}M$) did not influence spermatozoal AIB uptake. These results indicate a successful application of AIB to rooster spermatozoa as a mean for measuring sperm membrane function and suggest a possible alteration of membrane transport system in rooster spermatozoa between cold ($0{\sim}3^{\circ}C$) and cryopreservation ($-196^{\circ}C$).

• Toxicological Research
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• v.4 no.1
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• pp.37-45
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• 1988

Primary cultures of adult rat hepatocytes were used to study in vitro cytotoxic effects of T-2 toxin on liver cells. When T-2 toxin was added to the culture, a significant depression of the hormonal induction of ${\alpha}$-aminoisobutyric acid (AIB) uptake and tyrosine aminotransferase (TAT) activity was observed. However, T-2 toxin did not affect the uptake of ouabain into hepatocytes. Protein synthesis was inhibited by T-2 toxin, but RNA synthesis was not severely affected. The inhibitory effects of T-2 toxin on protein synthesis was diminished rapidly with culture time and the hepatocytes culture maintained control level of protein synthesis within 24 hrs.