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Nefiracetam
Nefiracetam is a nootropic drug of the racetam family. Preliminary research suggests that it may possess certain antidementia properties in rats. Effects Nefiracetam's cytoprotective actions are mediated by enhancement of GABAergic, cholinergic, and monoaminergic neuronal systems. Preliminary studies suggest that it improves apathy and motivation in post-stroke patients. It may also exhibit antiamnesia effects for the Alzheimer's type and cerebrovascular type of dementia. In addition, research in animal models suggests antiamnesic effects against a number of memory impairing substances, including: ethanol, chlorodiazepoxide, scopolamine, bicuculline, picrotoxin, and cycloheximide. Pharmacology Unlike other racetams, nefiracetam shows high affinity for the GABAA receptor ( IC50) = 8.5 nM), where it is presumed to be an agonist. It was able to potently inhibit 80% of muscimol binding to the GABAA receptor, although it failed to displace the remaining 20% of specific musci ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Racetam
Racetams, also sometimes known simply as pyrrolidones, are a class of drugs that share a pyrrolidone nucleus. Many, but not all, specifically have a 2- oxo-1- pyrrolidine acetamide (piracetam) nucleus. Some racetams, such as piracetam, aniracetam, oxiracetam, pramiracetam, and phenylpiracetam, are considered nootropics. Phenylpiracetam is also a stimulant. Others, such as levetiracetam, brivaracetam, and seletracetam, are anticonvulsants. Mechanism There is no universally accepted mechanism of action for racetams. Racetams generally show negligible affinity for common central nervous system receptors, but modulation of central neurotransmitters, including acetylcholine and glutamate, has been reported. Although aniracetam and nebracetam show some affinity for muscarinic acetylcholine receptors, only nefiracetam demonstrates nanomolar interactions with neurotransmitter receptors. Modification of membrane-located mechanisms of central signal transduction is another hypothesis. Li ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Racetams
Racetams, also sometimes known simply as pyrrolidones, are a class of drugs that share a 2-pyrrolidone, pyrrolidone nucleus. Many, but not all, specifically have a 2-carbonyl group, oxo-1-pyrrolidine acetamide (piracetam) nucleus. Some racetams, such as piracetam, aniracetam, oxiracetam, pramiracetam, and phenylpiracetam, are considered nootropics. Phenylpiracetam is also a stimulant. Others, such as levetiracetam, brivaracetam, and seletracetam, are anticonvulsants. Mechanism There is no universally accepted mechanism of action for racetams. Racetams generally show negligible affinity (pharmacology), affinity for common central nervous system receptor (biochemistry), receptors, but modulation of central neurotransmitters, including acetylcholine and glutamate, has been reported. Although aniracetam and nebracetam show some affinity for muscarinic acetylcholine receptors, only nefiracetam demonstrates nanomolar interactions with neurotransmitter receptors. Modification of membran ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nootropic
Nootropics ( or ) (colloquially brain supplements, smart drugs, cognitive enhancers, memory enhancers, or brain boosters) are chemical substances which purportedly improve cognitive functions, such as attention, memory, wakefulness, and self-control. In the United States, nootropics can be over-the-counter drugs and commonly advertised with unproven claims of effectiveness for improving cognition. The Federal Trade Commission and FDA have warned manufacturers and consumers about possible advertising fraud and marketing scams concerning nootropic supplements. Nootropics include both prescription drugs and dietary supplements marketed to enhance brain function, but while FDA-approved drugs have proven benefits and oversight, many dietary supplements lack evidence, may contain unapproved or hidden drugs, and pose safety and regulatory risks.Nootropics: Drugs vs Dietary Supplements for Brain Health. Operation Supplement Safety. https://www.opss.org/article/nootropics-drugs- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phenibut
Phenibut, sold under the brand name Anvifen among others, is a central nervous system (CNS) depressant with anxiolytic effects, and is used to treat anxiety, insomnia, and for a variety of other indications. It is usually taken oral administration, orally (swallowed by mouth), but may be given intravenously. Side effects of phenibut can include sedation, sleepiness, nausea, irritability, psychomotor agitation, agitation, dizziness, euphoria, and sometimes headache, among others. Overdose of phenibut can produce marked central nervous system depression including unconsciousness. The medication is structurally related to the neurotransmitter γ-aminobutyric acid (GABA), and hence is a GABA analogue. Phenibut is thought to act as a GABAB receptor, GABAB receptor agonist, similarly to baclofen and γ-hydroxybutyrate (GHB). However, at low concentrations, phenibut mildly increases the concentration of dopamine in the brain, providing Stimulant, stimulatory effects in addition to the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Guvacine
Guvacine is a tetrahydropyridine alkaloid found in areca nuts. It is the ''N''-demethylated derivative of arecaidine and the product of ester hydrolysis of guvacoline, both of which are also found in areca nuts as well. It is also an inhibitor of gamma-aminobutyric acid GABA (gamma-aminobutyric acid, γ-aminobutyric acid) is the chief inhibitory neurotransmitter in the developmentally mature mammalian central nervous system. Its principal role is reducing neuronal excitability throughout the nervous system. GA ... uptake. Lime hydrolyzes guvacoline to guvacine. References {{GABA metabolism and transport modulators Alkaloids Beta-Amino acids GABA reuptake inhibitors ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Seizure
A seizure is a sudden, brief disruption of brain activity caused by abnormal, excessive, or synchronous neuronal firing. Depending on the regions of the brain involved, seizures can lead to changes in movement, sensation, behavior, awareness, or consciousness. Symptoms vary widely. Some seizures involve subtle changes, such as brief lapses in attention or awareness (as seen in absence seizures), while others cause generalized convulsions with loss of consciousness ( tonic–clonic seizures). Most seizures last less than two minutes and are followed by a postictal period of confusion, fatigue, or other symptoms. A seizure lasting longer than five minutes is a medical emergency known as status epilepticus. Seizures are classified as provoked, when triggered by a known cause such as fever, head trauma, or metabolic imbalance, or unprovoked, when no immediate trigger is identified. Recurrent unprovoked seizures define the neurological condition epilepsy. Clinical features Seizur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bicuculline
Bicuculline is a phthalide-isoquinoline compound that is a light-sensitive competitive antagonist of GABAA receptors. It was originally identified in 1932 in plant alkaloid extracts and has been isolated from ''Dicentra cucullaria'', '' Adlumia fungosa'', and several ''Corydalis'' species (all in subfamily Fumarioideae, previously known as family Fumariaceae). Since it blocks the inhibitory action of GABA receptors, the action of bicuculline mimics epilepsy; it also causes convulsions. This property is utilized in laboratories around the world in the ''in vitro'' study of epilepsy, generally in hippocampal or cortical neurons in prepared brain slices from rodents. This compound is also routinely used to isolate glutamatergic (excitatory amino acid) receptor function. The action of bicuculline is primarily on the ionotropic GABAA receptors, which are ligand-gated ion channels concerned chiefly with the passing of chloride ions across the cell membrane, thus promoting an inhibi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Picrotoxin
Picrotoxin, also known as cocculin, is a poisonous crystalline plant compound. It was first isolated by the French pharmacist and chemist Pierre François Guillaume Boullay (1777–1869) in 1812. The name "picrotoxin" is a combination of the Greek words "picros" (bitter) and "toxicon" (poison). A mixture of two different compounds, picrotoxin occurs naturally in the fruit of the ''Anamirta cocculus'' plant, although it can also be synthesized chemically. Due to its interactions with the inhibitory neurotransmitter GABA, picrotoxin acts as a stimulant and convulsant. It mainly impacts the central nervous system, causing seizures and respiratory paralysis in high enough doses. Chemical structure and synthesis Picrotoxin is an equiMole (unit), molar mixture of two compounds, picrotoxinin (C15H16O6; CAS# 17617-45-7) and picrotin (C15H18O7; CAS# 21416-53-5). Of the two compounds, picrotin is less active. Picrotoxin occurs naturally in the fruit of the ''Anamirta cocculus'', a climb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amnesia
Amnesia is a deficit in memory caused by brain damage or brain diseases,Gazzaniga, M., Ivry, R., & Mangun, G. (2009) Cognitive Neuroscience: The biology of the mind. New York: W.W. Norton & Company. but it can also be temporarily caused by the use of various sedative and hypnotic drugs. The memory can be either wholly or partially lost due to the extent of damage that is caused. There are two main types of amnesia: * Retrograde amnesia is the inability to remember information that was acquired before a particular date, usually the date of an accident or operation. In some cases, the memory loss can extend back decades, while in other cases, people may lose only a few months of memory. * Anterograde amnesia is the inability to transfer new information from the short-term store into the long-term store. People with anterograde amnesia cannot remember things for long periods of time. These two types are not mutually exclusive; both can also occur simultaneously. Case stud ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Agonist
An agonist is a chemical that activates a Receptor (biochemistry), receptor to produce a biological response. Receptors are Cell (biology), cellular proteins whose activation causes the cell to modify what it is currently doing. In contrast, an Receptor antagonist, antagonist blocks the action of the agonist, while an inverse agonist causes an action opposite to that of the agonist. Etymology The word originates from the Ancient Greek, Greek word (''agōnistēs''), "contestant; champion; rival" < (''agōn''), "contest, combat; exertion, struggle" < (''agō''), "I lead, lead towards, conduct; drive." Types of agonists Receptor (biochemistry), Receptors can be activated by either endogenous agonists (such as hormones and neurotransmitters) or exogenous agonists (such as medication, drugs), resulting in a biological response. A physiological agonism an ...[...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Muscimol
Muscimol, also known as agarin or pantherine, as well as 5-(aminomethyl)-1,2-oxazol-3-ol, is the principal psychoactive constituent of ''Amanita muscaria'' and '' Amanita pantherina''. Muscimol is an isoxazole alkaloid and a potent and selective orthosteric agonist for the GABAA receptor It displays sedative-hypnotic, depressant and hallucinogenic psychoactivity. It is widely used to study GABAergic function in the brain. Muscimol is under investigation for its potential to treat anxiety, insomnia, and neurological disorders, though its psychoactive nature requires careful regulation. A systematic review and meta-analysis of 22 studies found that muscimol reduces neuropathic pain symptoms, with effects beginning within 15 minutes and lasting up to three hours. Muscimol was tested in small clinical trials between 1977 and 1982 for conditions like schizophrenia, Huntington’s disease, and tardive dyskinesia, but showed limited efficacy and was eventually supplanted by the re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IC50
Half maximal inhibitory concentration (IC50) is a measure of the potency of a substance in inhibiting a specific biological or biochemical function. IC50 is a quantitative measure that indicates how much of a particular inhibitory substance (e.g. drug) is needed to inhibit, ''in vitro'', a given biological process or biological component by 50%. The biological component could be an enzyme, cell, cell receptor or microbe. IC50 values are typically expressed as molar concentration. IC50 is commonly used as a measure of antagonist drug potency in pharmacological research. IC50 is comparable to other measures of potency, such as EC50 for excitatory drugs. EC50 represents the dose or plasma concentration required for obtaining 50% of a maximum effect ''in vivo''. IC50 can be determined with functional assays or with competition binding assays. Sometimes, IC50 values are converted to the pIC50 scale. :\ce = -\log_ \ce Due to the minus sign, higher values of pIC50 indicate ex ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
