Cathinone

Cathinone is a monoamine alkaloid found in the shrub Catha edulis and is chemically similar to ephedrine, cathine, methcathinone and other amphetamines. It is probably the main contributor to the stimulant effect of Catha edulis, also known as khat.

Cathinone differs from many other amphetamines in that it has a ketone functional group. Other phenethylamines that share this structure include the stimulants methcathinone, MDPV, mephedrone and the antidepressant bupropion.

Cathinone Mechanism Of Action

Cathinone has been found to stimulate the release of dopamine and inhibit the reuptake of epinephrine, norepinephrine and serotonin in the central nervous system (CNS). These neurotransmitters are all considered monoamines and share the general structure of an aromatic ring and an amine group attached by a two-carbon separator. Because cathinone is a hydrophobic molecule, it can easily cross cell membranes and other barriers, including the blood–brain barrier.

This property allows it to interact with the monoamine transporters in the synaptic cleft between neurons. Cathinone induces the release of dopamine from brain striatal preparations that are prelabelled either with dopamine or its precursors.

The metabolites of cathinone, cathine and norephedrine, also possess CNS stimulation, but create much weaker effects. The effects of cathinone on the body can be countered by a preceding administration of a dopamine receptor antagonist. The antagonist prevents synaptic dopamine released by cathinone from exerting its effect by binding to dopamine receptors.

Cathinone can also affect cholinergic concentrations in the gut and airways by blocking prejunctional adrenergic receptors (α₂ adrenergic) and activating 5-HT7 receptors, thereby inhibiting smooth muscle contraction. It can also induce dry mouth, blurred vision and increased blood pressure and heart rate.

Catha Edulis Pharmacology

Khat leaves are removed from the plant stalk and are kept in a ball in the cheek and chewed. Chewing releases juices from the leaves, which include the alkaloid cathinone. The absorption of cathinone has two phases: one in the buccal mucosa and one in the stomach and small intestine. The stomach and small intestine are very important in the absorption of ingested alkaloids. At approximately 2.3 hours after chewing khat leaves, the maximum concentration of cathinone in blood plasma is reached. The mean residence time is 5.2 ± 3.4 hours. The elimination half-life of cathinone is 1.5 ± 0.8 hours. A two-compartment model for absorption and elimination best describes this data.

Eutylone Crystal