Video Experimental Relacionado
Updated: Jul 5, 2026
15:05
Functional Evaluation of Biological Neurotoxins in Networked Cultures of Stem Cell-derived Central Nervous System Neurons
Published on: February 5, 2015
Neurotoxicidad de la dexfenfluramina en el cerebro de primates no humanos
G A Ricaurte1, M E Molliver, M B Martello
1Department of Neurology, Francis Scott Key Medical Center, Johns Hopkins School of Medicine, Baltimore, Maryland 21224.
Lancet (London, England)
|December 14, 1991
Resumen
Se descubrió que la dexfenfluramina, un supresor del apetito, dañaba las neuronas cerebrales de serotonina (5-HT) en monos. Esta neurotoxicidad plantea preocupaciones sobre la seguridad del fármaco en humanos.
Área de la Ciencia:
- La neurociencia es la neurociencia.
- Farmacología Farmacología.
- Toxicología Toxicología.
Sus antecedentes:
- La dexfenfluramina es un supresor del apetito.
- Las neuronas de serotonina (5-HT) son cruciales para varias funciones cerebrales.
- Los posibles efectos neurotóxicos de la dexfenfluramina requieren una investigación.
Objetivo del estudio:
- Para evaluar el potencial neurotóxico de la dexfenfluramina en las neuronas de serotonina (5-HT) en primates no humanos.
Principales métodos:
- A los monos ardilla se les administró dexfenfluramina por vía subcutánea dos veces al día durante cuatro días.
- Las dosis administradas fueron de 1,25 mg/kg o 5,00 mg/kg.
- Se realizaron evaluaciones neuroquímicas y morfológicas dos semanas después del tratamiento.
Principales resultados:
- Se observó una disminución relacionada con la dosis de serotonina (5-HT) y ácido 5-hidroxiindoleacético.
- Se detectó una reducción en los sitios de captación de 5-HT.
- Los estudios morfológicos revelaron cambios axonales agudos y una disminución persistente en la densidad del axón 5-HT.
Conclusiones:
- La dexfenfluramina causa daño a las neuronas centrales de serotonina (5-HT) en los monos.
- Los hallazgos sugieren una potencial neurotoxicidad de la dexfenfluramina en humanos.
- Se necesita más investigación para comprender las implicaciones a largo plazo.
Videos de Conceptos Relacionados
01:24Resting Membrane Potential
The relative difference in electrical charge, or voltage, between the inside and the outside of a cell membrane, is called the membrane potential. It is generated by differences in permeability of the membrane to various ions and the concentrations of these ions across the membrane.
The Inside of a Neuron is More Negative
The membrane potential of a cell can be measured by inserting a microelectrode into a cell and comparing the charge to a reference electrode in the extracellular fluid. The...
The Inside of a Neuron is More Negative
The membrane potential of a cell can be measured by inserting a microelectrode into a cell and comparing the charge to a reference electrode in the extracellular fluid. The...
01:26Neurochemical Transmission: Sites of Drug Action
Neurochemical transmission, the conduction of electrical impulses between neurons mediated by neurotransmitters, plays a vital role in various physiological processes. Autonomic drugs exert their effects by modulating neurotransmission within the autonomic nervous system. For instance, drugs such as hemicholinium block the precursor uptake necessary for synthesizing acetylcholine, an essential autonomic neurotransmitter. Following synthesis, neurotransmitters are stored in vesicles. Metyrosine...
01:21Drugs 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...
01:29Drugs 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...
01:24CNS Stimulants: Cocaine, Amphetamines and Cannabinoids
CNS stimulants, such as cocaine, amphetamines, and cannabinoids, have varying structures and mechanisms of action that lead to different therapeutic effects and side effects. Cocaine, with its molecular formula C17H21NO4, is a tropane alkaloid and a tertiary amino compound. It has two chemical forms: the hydrochloride salt and the "freebase." The former is in powder form, while the latter involves removing the hydrochloride salt to create a form that can be smoked. Cocaine exerts its effects by...
01:22CNS Stimulants: Psychedelic Agents
Hallucinogens, also known as psychedelic drugs, are a class of substances known for their ability to alter perception, cognition, and emotions. Despite their profound effects on the mind, these drugs are non-addictive, setting them apart from many other abused substances. The mechanism of action of these drugs lies in their impact on the 5-HT2A receptor in the brain. Upon activation, this receptor couples to Gq-type G proteins, triggering a cascade that releases intracellular calcium. This...