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HPTP
HPTP is a monoaminergic neurotoxin related to MPTP. It is the dehydration product of haloperidol. The agent is specifically a dopaminergic and serotonergic neurotoxin. HPTP is a prodrug A prodrug is a pharmacologically inactive medication or compound that, after intake, is metabolized (i.e., converted within the body) into a pharmacologically active drug. Instead of administering a drug directly, a corresponding prodrug can be ... of HPP+, which mediates its monoaminergic neurotoxicity. This is analogous to how MPP+ mediates the neurotoxicity of MPTP. Other related compounds include RHPTP and RHPP+. References 4-Chlorophenyl compounds 4-Fluorophenyl compounds Monoaminergic neurotoxins Prodrugs Tetrahydropyridines {{Nervous-system-drug-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Serotonergic Neurotoxin
A monoamine neurotoxin, or monoaminergic neurotoxin, is a drug that selectively damages or destroys monoaminergic neurons. Monoaminergic neurons are neurons that signal via stimulation by monoamine neurotransmitters including serotonin, dopamine, and norepinephrine. Examples of monoamine neurotoxins include the serotonergic neurotoxins ''para''-chloroamphetamine (PCA), methylenedioxymethamphetamine (MDMA), and 5,7-dihydroxytryptamine (5,7-DHT); the dopaminergic neurotoxins oxidopamine (6-hydroxydopamine), MPTP, and methamphetamine; and the noradrenergic neurotoxins oxidopamine and DSP-4. In the case of serotonergic neurotoxins like MDMA, research suggests that simultaneous induction of serotonin and dopamine release, serotonin depletion, dopamine uptake and metabolism, hyperthermia, oxidative stress and antioxidant depletion, and/or drug metabolites may all be involved in the neurotoxicity. On the other hand, there is evidence that drug metabolites may not be involved. So ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HPP+
HPP+, also known as haloperidol pyridinium, is a monoaminergic neurotoxin and a metabolite of haloperidol. Formation and metabolism HPP+ is formed from haloperidol, and its dehydration product HPTP, by CYP3A enzymes in the liver. The compound can cross the blood–brain barrier and has been detected in the brain following haloperidol administration in both animals and humans. Neurotoxicity HPP+ is structurally related to the selective dopaminergic neurotoxin MPTP (and its active metabolite MPP+), which induces Parkinson's disease-like symptoms in humans. HPP+ is a neurotoxin specifically affecting serotonergic and dopaminergic neurons, and its neurotoxicity resembles that of MPTP. Extrapyramidal symptoms (EPS) HPP+ may contribute to the development of extrapyramidal symptoms (EPS) in patients undergoing long-term haloperidol therapy. An alternative theory posits that these symptoms result from long-term dopamine receptor Dopamine receptors are a class of G pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MPTP
MPTP (1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine) is an organic compound. It is classified as a tetrahydropyridine. It is of interest as a precursor to the monoaminergic neurotoxin MPP+, which causes permanent symptoms of Parkinson's disease by destroying dopaminergic neurons in the substantia nigra of the brain. It has been used to study disease models in various animals. While MPTP itself has no psychoactive effects, the compound may be accidentally produced during the manufacture of MPPP, a synthetic opioid drug with effects similar to those of morphine and pethidine (meperidine). The Parkinson-inducing effects of MPTP were first discovered following accidental injection as a result of contaminated MPPP. Toxicity Injection of MPTP causes rapid onset of Parkinsonism, hence users of MPPP contaminated with MPTP will develop these symptoms. MPTP itself is not toxic, but it is a lipophilic compound and can therefore cross the blood–brain barrier. Once inside the brai ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prodrug
A prodrug is a pharmacologically inactive medication or compound that, after intake, is metabolized (i.e., converted within the body) into a pharmacologically active drug. Instead of administering a drug directly, a corresponding prodrug can be used to improve how the drug is absorbed, distributed, metabolized, and excreted (ADME). Prodrugs are often designed to improve bioavailability when a drug itself is poorly absorbed from the gastrointestinal tract. A prodrug may be used to improve how selectively the drug interacts with cells or processes that are not its intended target. This reduces adverse or unintended effects of a drug, especially important in treatments like chemotherapy, which can have severe unintended and undesirable side effects. History Many herbal extracts historically used in medicine contain glycosides (sugar derivatives) of the active agent, which are hydrolyzed in the intestines to release the active and more bioavailable aglycone. For example, sal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
