GT1b ganglioside induces death of dopaminergic neurons in rat mesencephalic cultures.

We examined neurotoxicity of GT1b against dopaminergic neurons in vitro. Cultures of mesencephalic cells deprived of serum underwent the loss of 19% of tyrosine hydroxylase immunopositive (TH-ip) neurons. In cultures deprived of serum, treatment with 10-30 microg/ml GT1b attenuated the number of TH-ip neurons by 26-69%, respectively, compared to non-treated cultures.

Pattern of deposition of stainless steel welding fume particles inhaled into the respiratory systems of Sprague-Dawley rats exposed to a novel welding fume generating system.

In order to investigate occupational diseases related to welding fume exposure, such as nasal septum perforation, pneumoconiosis and manganese intoxication, we built a welding fume exposure system that included a welding fume generator, exposure chamber and fume collector. The fume concentrations in the exposure chamber were monitored every 15 min during a 2-h exposure. Fume (mg/m(3)) concentrations of major metals, including Fe, Mn, Cr, and Ni were found to be consistently maintained.

History of the Korean GLPs and the activities and perspectives of the Korean Society of GLP.

The Korean Society of Good Laboratory Practice (KSGLP) was established Dec. 10, 1998. The objectives of the KSGLP are to enhance the quality of domestic studies and the level of GLP compliance, in safety testing, and to promote information exchange among its members.

Melatonin increases striatal dopaminergic function in 6-OHDA-lesioned rats.

The purpose of this study was to assess the in vivo effects of melatonin, as an antioxidant, on striatal dopaminergic function in rats with a unilateral 6-hydroxydopamine (6-OHDA) lesion of the striatum. Compared with sham-operated controls and expressed as a ratio relative to the contralateral side, there was an increase in the lipid peroxidation product malondialdehyde (MDA, 142%) and a significant reduction in tyrosine hydroxylase (TH) enzyme activity (28%) and dopamine (DA, 32%) and its metabolite dihydroxyphenylacetic acid (DOPAC, 50%) 2 weeks after 6-OHDA injection. Melatonin treatment almost completely restored MDA levels to normal, suggesting the in vivo action of melatonin as an antioxidant.

Reproductive toxicity of 2-bromopropane in Sprague Dawley rats.

Objectives: In an effort to clarify the mass intoxication of workers at an electronic company in Korea, the possible causative chemical for reproductive toxicity, 2-bromopropane (2BP), was investigated.

Methods: 2BP was tested through the use of repeated dose experiments among male Sprague Dawley rats. Ten rats were assigned to each treatment group.

Effects of 2-bromopropane on the female reproductive function in Sprague-Dawley rats.

2-Bromopropane (2BP) has been implicated to be the reason for the mass intoxication of workers at an electronic company in Korea. A case series study indicated that 2BP was the possible causative chemical for reproductive toxicity, causing severe anemia accompanied by amenorrhea among female workers, and azoospermia or oligospermia among male workers. To clarify the effect of 2BP on the female reproductive function, repeated doses of 2BP were tested on female Sprague-Dawley rats for 21 days.

Mutagenicity of 2-bromopropane.

2-Bromopropane (2BP, isopropyl bromide), a substitute for freon, has recently been suspected to be the causative chemical for the outbreak of some reproductive dysfunctions such as amenorrhea and oligospermia in workers who has been exposed to this solvent in an electronic factory. Bacterial mutation assays, chromosome aberration analysis in vitro, and micronucleus tests in vivo, were carried out to clarify the mutagenicity of 2BP. 2BP induced mutagenicity in Salmonella typhimurium TA100 with metabolic activation in a dose-dependant manner.