まとめ
神経性麻酔薬は,ドーパミン受容体を阻害することで,カタレプシーを引き起こす. この研究は,動物におけるハロペリドール誘発のカタレプシーが,ストレイタルニューロンにポストシナプス的に位置するドーパミン受容体によって媒介されていることを示しています.
科学分野:
- 神経科学は神経科学である.
- 薬理学 薬理学とは
背景:
- ハロペリドールなどの神経麻痺薬は,ドーパミン受容体を遮断し,動物ではカタレクシーを誘発する.
- 以前の研究では,状ドーパミン受容体がカタレプシーに関与していることが判明したが,傷害方法により,前シナプスと後シナプスの役割を区別することができなかった.
研究 の 目的:
- ニューロレプティック誘発のカタレプシーにおけるポストシナプティックとプレシナプティックのストライタルドーパミン受容体の特定の役割を調査する.
主な方法:
- カイン酸を利用して,ポストシナプスドーパミン受容体を選択的に破壊する.
- 前シナプスドーパミン受容体を選択的に破壊するために,皮質の剥離を用いた.
主要な成果:
- ハロペリドール誘発のカタレプシーは,ポストシナプスドーパミン受容体の破壊後に著しく減少しました.
- プレシナプスドーパミン受容体の破壊は,カタレプシーを廃止しなかった.
結論:
- ハロペリドールの触覚作用は,主に線状神経細胞にポストシナプス的に位置するドーパミン受容体によって媒介されます.
関連する概念動画
Adrenergic Agonists: Indirect-Acting Agents
Indirect-acting adrenergic agonists potentiate the effects of endogenous catecholamines through different mechanisms without directly binding to adrenoceptors.
One mechanism involves depleting stored catecholamines by displacing them from synaptic vesicles. These agents, known as "displacers," are transported into vesicles at the expense of noradrenaline. Examples include amphetamine and tyramine, which lack a catechol moiety, resulting in prolonged action, improved oral bioavailability, and...
One mechanism involves depleting stored catecholamines by displacing them from synaptic vesicles. These agents, known as "displacers," are transported into vesicles at the expense of noradrenaline. Examples include amphetamine and tyramine, which lack a catechol moiety, resulting in prolonged action, improved oral bioavailability, and...
Drugs Affecting Neurotransmitter Release or Uptake
Certain drugs can affect how neurotransmitters called catecholamines, are released or taken back up in the adrenergic neuron. They can have different effects on the body's sympathetic transmission. Reserpine, a natural compound found in the Rauwolfia shrub, blocks a transporter called vesicular monoamine transporter (VMAT), which leads to a buildup of catecholamines in the cell and reduces sympathetic transmission. Another drug called guanethidine works in multiple ways, including blocking...
Drugs Affecting Neurotransmitter Synthesis
Drugs affecting neurotransmitter synthesis can impact the adrenergic neuron and the synthesis of neurotransmitters. For example, α-methyltyrosine and carbidopa target specific enzymes involved in catecholamine synthesis. α-methyltyrosine inhibits the enzyme tyrosine hydroxylase, which converts tyrosine into dopamine. By blocking this enzyme, α-methyltyrosine reduces dopamine production and other catecholamines. Carbidopa, on the other hand, inhibits the enzyme dopa decarboxylase, which converts...
Parkinson's Disease: Treatment
Neurodegenerative disorders, such as Parkinson's Disease (PD), involve the gradual and irreversible destruction of neurons in particular brain areas. These disorders exhibit standard features like proteinopathies, selective vulnerability of some neurons, and an interaction of intrinsic properties, genetics, and environmental influences in neural injury.
Parkinson's Disease is primarily a result of the loss of dopaminergic neurons in the substantia nigra pars compacta. The cornerstone of its...
Parkinson's Disease is primarily a result of the loss of dopaminergic neurons in the substantia nigra pars compacta. The cornerstone of its...
Drugs Affecting GI Tract Motility: Dopamine Receptor Antagonists
Prokinetic agents are specialized medications that stimulate gastrointestinal (GI) motility, promoting food movement through the GI tract. Dopamine, an inhibitory neurotransmitter, plays a significant role in this process, reducing GI motility and indirectly controlling the speed of digestion. Dopamine receptor antagonists, such as metoclopramide and domperidone, offer a unique advantage as prokinetic agents. By blocking the dopamine receptors, these drugs increase GI motility, improving food...
Chemotherapy-Induced Nausea and Vomiting: Dopamine Receptor Antagonists
Dopamine receptor antagonists, also known as antipsychotic agents, are critical in managing chemotherapy-induced vomiting. These antiemetic agents block dopamine receptors in the chemoreceptor trigger zone (CTZ), inhibiting signal transmission to the vomiting center. Antipsychotic agents encompass phenothiazines (PTZ), butyrophenones, benzamides, and thienobenzodiazepines (Zyprexa), which are utilized for their antiemetic and sedative properties.
Phenothiazines, such as prochlorperazine...
Phenothiazines, such as prochlorperazine...


