• The Korean Journal of Physiology and Pharmacology
• /
• 제18권2호
• /
• pp.129-134
• /
• 2014

It has been suggested that transition metal ions such as iron can produce an oxidative injuries to nigrostriatal dopaminergic neurons, like Parkinson's disease (PD) and subsequent compensative increase of tetrahydrobiopterin ($BH_4$) during the disease progression induces the aggravation of dopaminergic neurodegeneration in striatum. It had been established that the direct administration of $BH_4$ into neuron would induce the neuronal toxicity in vitro. To elucidate a role of $BH_4$ in pathogenesis in the PD in vivo, we assessed the changes of dopamine (DA) and $BH_4$ at striatum in unilateral intranigral iron infused PD rat model. The ipsistriatal DA and $BH_4$ levels were significantly increased at 0.5 to 1 d and were continually depleting during 2 to 7 d after intranigral iron infusion. The turnover rate of $BH_4$ was higher than that of DA in early phase. However, the expression level of GTP-cyclohydrolase I mRNA in striatum was steadily increased after iron administration. These results suggest that the accumulation of intranigral iron leads to generation of oxidative stress which damage to dopaminergic neurons and causes increased release of $BH_4$ in the dopaminergic neuron. The degenerating dopaminergic neurons decrease the synthesis and release of both $BH_4$ and DA in vivo that are relevance to the progression of PD. Based on these data, we propose that the increase of $BH_4$ can deteriorate the disease progression in early phase of PD, and the inhibition of $BH_4$ increase could be a strategy for PD treatment.

• 대한약침학회지
• /
• 제3권1호
• /
• pp.65-87
• /
• 2000

This study was designed to evaluate the effect of the bee venom(BV) aqua-acupuncture on the neuronal activities of catecholaminergic(tyrosine hydroxylase : TH, dopamine ${\beta}$ hydroxylase : D${\beta}$H) system in the brainstem. After the BV aqua-acupuncture was applied on Chok-Samni(ST36) and the gluteal part(Blank locus) in rats. Also, the number of colocalization between catecholamine containing neurons and Fos immunoreactive neurons were analyzed by using the double immunohistochemical technique. The results of the experiments were summarized as follows : 1. In DR and LC, Chok-Samni group and the Blank locus group showed more significant increase in the number of colocalization between TH containing neurons and Fos immunoreactive neurons than the control group. Furthermore, Chok-Samni group showed more significant increase than the Blank locus group. Also, in Arc, Chok-Samni group showed more significant increase than the Blank locus group and the control group. 2. In LC, Chok-Samni group showed more significant increase in the number of colocalization between D${\beta}$H containing neurons and Fos immunoreactive neurons than the Blank locus group and the control group. Also, in A5, Chok-Samni group and the Blank locus group showed more significant increase than the control group. Chok-Samni group showed more significant increase than the Blank locus group. However, there was no significant change in A7. Consequently, the BV aqua-acupuncture increased more potent the number of Fos immunoreactive neurons and the activity of catecholaminergic neurons. Furthermore, the BV aqua-acupuncture was more effective on Chok-Samni than Blank locus group. These results indicate that the BV aqua-acupuncture is very effective therapy to control pain. The therapeutic effect of BV aqua-acupunture may associated with the endogenous modulatory system such as catecholamine. Those data from the study can be applied to establish the effective treatment of the BV for pain control in the clinical field.

• 대한수의학회지
• /
• 제37권3호
• /
• pp.499-508
• /
• 1997

The distributions and morphological characteristics of neurons displaying immunoreactivity to the catecholamine synthetic enzymes, tyrosine hydroxylase(TH), dopamine-${\beta}$-hydroxylase(DBH), and phenylethanolamine-N-methyltransferase (PNMT) were examined in the adjacent sections of the olfactory bulb of the Striped Field Mouse(Apodemus agrarius coreae). None of these cell groups displayed either DBH or PNMT immunoreactivity. Many TH-immunoreactive neurons were present in the olfactory bulb. The vast majority of such cells occurred in the glomerular layer as periglomerular cells surrounding the glomeruli. Numerous addtional cells were present in the external plexiform layer, and scattered in the mitral cell layer and internal plexiform layer. Also TH-immunoreactive neurons were found in the glomerular layer and granular layer of the accessory olfactory bulb.

• The Korean Journal of Physiology and Pharmacology
• /
• 제11권4호
• /
• pp.139-144
• /
• 2007

Recent studies suggest that alterations in glutamate receptor subunit levels in mesocorticolimbic dopamine areas could account for neural adaptations in response to psychostimulant drugs. Although many drugs of abuse induce changes in ionotropic glutamate receptor subunits in mesocorticolimbic dopamine areas, the changes of ionotropic glutamate receptor subunits by repeated nicotine treatment in these areas are not known. To answer this question, we injected male Sprague-Dawley rats twice daily with nicotine (0.4 mg/kg) or saline (1 ml/kg) for 10 days. The immunoreactivity of NR1, GluR1, and GluR2 glutamate receptor subunits was examined $16{\sim}18 h$ after the last injection of saline or nicotine. Repeated nicotine treatment significantly increased NR1 levels in the ventral tegmental area (VTA). In addition, repeated nicotine treatment showed a tendency towards an increase in GluR1 levels in the VTA as well as in striatum. However, there was no significant change in glutamate receptor subunits in other areas including nucleus accumbens (NAc). These results demonstrate that repeated nicotine treatment increases NR1 levels in VTA similarly to other drugs of abuse, suggesting that elevated glutamate receptor subunits in the VTA, but not NAc may be involved in the excitation of mesocorticolimbic dopamine neurons by nicotine.

• 한국환경과학회지
• /
• 제31권5호
• /
• pp.423-429
• /
• 2022

Parkinson's Disease (PD) is a chronic neurodegenerative disorder caused by the progressive loss of dopaminergic neurons, leading to decreased dopamine levels in the midbrain. Although the specific etiology of PD is not yet known, oxidative stress, inflammation, and subsequent apoptosis have been proposed to be closely related to PD pathophysiology. Cera Flava (CF) is a natural extract obtained from beehives and is isolated through the heating, compression, filtration, and purification of beehives. CF has been used in traditional medicines for its various clinical and pharmacological effects. However, its effects on neurodegenerative diseases are unknown. Therefore, we investigated the effects of CF against 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced PD in mice and explored the underlying mechanism of action. In MPTP-induced PC12 cells, CF protected NADH dehydrogenase activity and inhibited lactate dehydrogenase. In the mouse model, CF promoted recovery from movement impairments, prevented dopamine depletion, and protected against MPTP-induced dopaminergic neuronal degradation. Moreover, CF downregulated glial and microglial activation. Taken together, our results suggest that CF improves behavioral impairments and protects against dopamine depletion in MPTP-induced toxicity by inhibiting glial and microglial activation.

• BMB Reports
• /
• 제29권2호
• /
• pp.151-155
• /
• 1996

To swimming motor neurons (SMNs) of Polyorchis penicillatus, a hydrozoan medusae, dopamine (DA) acts as an inhibitory neurotransmitter by hyperpolarizing its membrane potential and decreasing its firing rate as well. Such an inhibitory action of DA is caused by an increased permeability to potassium (K) ions. To investigate whether voltage-gated K channels are directly responsible for the membrane hyperpolarization induced by DA, we employed whole-cell voltage clamp configuration. One ${\mu}M$ DA applied to SMNs increased the peak and rear values of voltage-gated K currents by 37 and 54%, respectively, in a reversible manner. Combined with subtraction analysis, this result suggests that the outflux of K ions by DA in SMNs occurs mainly through rectifier-like K channels.

• 로봇학회논문지
• /
• 제1권2호
• /
• pp.163-171
• /
• 2006

This paper introduces the research progress on the artificial brain in the Telerobotics and Control Laboratory at KAIST. This series of studies is based on the assumption that it will be possible to develop an artificial intelligence by copying the mechanisms of the animal brain. Two important brain mechanisms are considered: spike-timing dependent plasticity and dopaminergic plasticity. Each mechanism is implemented in two coding paradigms: spike-codes and rate-codes. Spike-timing dependent plasticity is essential for self-organization in the brain. Dopamine neurons deliver reward signals and modify the synaptic efficacies in order to maximize the predicted reward. This paper addresses how artificial intelligence can emerge by the synergy between self-organization and reinforcement learning. For implementation issues, the rate codes of the brain mechanisms are developed to calculate the neuron dynamics efficiently.

• Applied Microscopy
• /
• 제32권2호
• /
• pp.175-183
• /
• 2002

한국 연근해산 살오징어와 서해낙지의 시엽에서 신경전달물질을 분비하는 neuron의 특성 및 기능을 확인하기 위해 rabbit anti-dopamine (TH)과 rabbit anti-calbindin-$D_{28K}$ 등의 항체를 이용한 면역염색과 면역금지법을 시행한 결과는 다음과 같았다. 항-dopamine을 사용한 면역염색 결과 살오징어에서는 외과립세포층 상단에 위치한 대형 무축삭세포와 수질부의 섬을 이루는 세포들 중 $2{\sim}3$개의 비교적 소량의 세포만이 양성반응을 보인 반면, 서해낙지에서는 외과립세포층 상단 및 중간 부위의 $2{\sim}3$개의 세포와 수질부섬을 이루는 5개 이상의 세포에서 강한 양성반응을 보였다. 항-calbindin-D28k인 경우는 살오징어의 외과립세포층 상단에 위치한 $2{\sim}3$개의 소형 무축삭세포와 내과립세포층 하단에 위치한 $1{\sim}2$개의 세포에서 양성반응을 보인 반면, 서해낙지인 경우는 외과립세포층에서 4개 정도의 세포에서 양성 반응을 보였으나, 내과립세포층에서는 반응을 확인할 수 없었다. 면역금지법을 시행한 결과 살오징어에서는 항-dopamine과 항-calbindin에 면역반응을 보인 세포들의 세포질 $0.5{\mu}m^2$당 $17{\sim}26$개 정도의 비교적 많은 수의 금입자가 표지된 반면, 서해낙지에서는 세포질 $0.5{\mu}m^2$당 평균 10개 정도인 소량의 금입자만이 표지되어, 살오징어가 서해낙지에 비해 표지된 금입자가 거의 2배 정도 많았다.

• 한국독성학회:학술대회논문집
• /
• 한국독성학회 2001년도 International Symposium on Signal transduction in Toxicology
• /
• pp.124-124
• /
• 2001

Tetrahydropapaveroline(THP), a dopamine-derived 6,7-dihydroxy-l-(3',4'-dihydroxybenzyl)-1,2,3,4-tetrahydrosioquinoline, has been suspected as a possible dopaminergic neurotoxin to elicit Parkinsonism. Autoxidation or monoamine oxidase-mediated oxidation of THP and subsequent generation of reactive oxygen species (ROS) may contribute to the degeneration of dopaminergic neurons induced by this isoquinoline alkaloid.(omitted)

• 한국독성학회:학술대회논문집
• /
• 한국독성학회 2001년도 International Symposium on Dietary and Medicinal Antimutgens and Anticarcinogens
• /
• pp.114-114
• /
• 2001

Tetrahydropapaveroline (THP), a dopamine-derived 6, 7-dihydroxy-1-(3' ,4'-dihydroxybenzyl)-1,2,3,4-tetrahydroisoquinoline, has been suspected as a possible dopaminergic neurotoxin to elicit Parkinsonism. Autooxidation or enzymatic oxidation of THP and subsequent generation of reactive oxygen species (ROS) may contribute to the degeneration of dopaminergic neurons induced by this isoquinoline alkaloid.(omitted)