| Description: |
Cathinone is the main psychoactive constituent of the khat leaf and this alkaloid is a natural amphetamine, cathinone shares the action of amphetamine on CNS as well as its sympathomimetic effects, it induces significant behavioral changes and CNS activation in the hamster by systemic administration.Cathinone has amphetamine-like effects, it can produce increases in blood pressure and in heart rate, and these changes are concomitant with the presence of cathinone in blood plasma, it has in humans euphorigenic and psychostimulant effects. Cathinone has vasoconstrictor activity which is not due to indirect or direct sympathomimetic activity, the coronary vasoconstriction may explain the increased incidence of myocardial infarction in khat chewers, which may arise from coronary vasospasm.
|
| In vitro: |
| Auton Autacoid Pharmacol. 2003 Oct-Dec;23(5-6):319-26. | | Coronary and aortic vasoconstriction by cathinone, the active constituent of khat.[Pubmed: 15255816 ] | 1. The psychostimulant constituent of khat leaves, S-(-)-cathinone, was examined for vascular activity on the coronary vasculature of guinea-pig-isolated perfused hearts and aortic ring preparations.
METHODS AND RESULTS:
2. Cathinone caused coronary vasoconstriction, negative inotropy and negative chronotropy in isolated hearts. The major metabolite of cathinone after its ingestion, 1R.2S-(-)-norephedrine (norephedrine), also caused coronary vasoconstriction comparable with that by cathinone. Norephedrine, however, had no effect on force or rate of cardiac contractions. 3. Cocaine (10 microm) potentiated the coronary vasoconstriction and positive inotropy by noradrenaline indicating inhibition of neuronal uptake. The vasoconstriction and negative inotropy by cathinone, however, were not affected, indicating that its action was not via release of noradrenaline from sympathetic neurones. 4. The alpha(1)-adrenoceptor antagonist, prazosin, blocked the vasoconstriction by noradrenaline, but not that produced by cathinone in the presence of cocaine. This indicates that the coronary vasoconstriction by cathinone was not due to an action on alpha(1)-adrenoceptors either directly or indirectly through noradrenaline release. 5. Three repeated doses of cathinone displayed the same coronary vasoconstrictor responses, indicating a lack of tachyphylaxis and therefore confirming that the response was unlikely to be due to indirect sympathomimetic activity through release of noradrenaline. 6. In guinea-pig aortic rings, the order of vasoconstrictor activity was: noradrenaline > norephedrine > cathinone, with each causing approximately equivalent maximum responses. The time to reach plateau contractions was shortest for noradrenaline (5.1 +/- 0.5 min), then norephedrine (9.3 +/- 1.5 min) and cathinone the longest (25.4 +/- 3.2 min, 335 microm dose).
CONCLUSIONS:
7 These results indicate that cathinone has vasoconstrictor activity which is not due to indirect or direct sympathomimetic activity. The precise mechanism for this vasoconstriction remains to be determined. The coronary vasoconstriction may explain the increased incidence of myocardial infarction in khat chewers, which may arise from coronary vasospasm. |
|
| In vivo: |
| Eur J Pharmacol. 2015 Jul 5;758:142-6. | | Direct and indirect cardiovascular actions of cathinone and MDMA in the anaesthetized rat.[Pubmed: 25863258] | The stimulants cathinone (from Khat leaves) and methylenedioxymeth-amphetamine (MDMA) produce adrenoceptor mediated tachycardia and vasopressor actions that may be the result of direct receptor stimulation, actions on the noradrenaline transporter, and/or displacement of noradrenaline from nerve terminals.
METHODS AND RESULTS:
Effects of cathinone or MDMA were compared with those of the indirect sympathomimetic tyramine. Male Wistar rats were anaesthetized with pentobarbitone for blood pressure and heart rate recording. Some rats were sympathectomised by treatment with 6-hydroxydopamine. In the anaesthetised rat, cathinone, MDMA and tyramine (all 0.001-1 mg/kg) produced marked tachycardia, tyramine produced marked pressor responses and MDMA produced small pressor responses. The tachycardia to cathinone and MDMA was almost abolished by propranolol (1mg/kg). Pretreatment with cocaine (1mg/kg) did not significantly affect the tachycardia to cathinone or MDMA, but reduced the response to tyramine. However, in sympathectomised rats, the tachycardia to cathinone or MDMA was markedly attenuated, but the tachycardia to tyramine was only partially reduced. Blood pressure effects of tyramine and MDMA were also markedly attenuated by sympathectomy.
CONCLUSIONS:
The results demonstrate firstly that cocaine may not be the most suitable agent for assessing direct versus indirect agonism in cardiovascular studies. Secondly, the use of chemical sympathectomy achieved the desired goal of demonstrating that cardiac β-adrenoceptor mediated actions of cathinone and MDMA are probably largely indirect. | | Neurosci Lett. 2014 Jan 24;559:34-8. | | Cathinone increases body temperature, enhances locomotor activity, and induces striatal c-fos expression in the Siberian hamster.[Pubmed: 24287379] | Cathinone is a β-keto alkaloid that is the major active constituent of khat, the leaf of the Catha edulis plant that is chewed recreationally in East Africa and the Middle East. Related compounds, such as methCathinone and mephedrone have been increasing in popularity as recreational drugs, resulting in the recent proposal to classify khat as a Class C drug in the UK. There is still limited knowledge of the pharmacological effects of Cathinone.
METHODS AND RESULTS:
This study examined the acute effects of Cathinone on core body temperature, locomotor and other behaviors, and neuronal activity in Siberian hamsters. Adult male hamsters, previously implanted with radio telemetry devices, were treated with Cathinone (2 or 5mg/kg i.p.), the behavioral profile scored and core body temperature and locomotor activity recorded by radio telemetry. At the end of the study, hamsters received vehicle or Cathinone (5mg/kg) and neuronal activation in the brain was determined using immunohistochemical evaluation of c-fos expression. Cathinone dose-dependently induced significant (p<0.0001) increases in both temperature and locomotor activity lasting 60-90min. Cathinone (2mg/kg) increased rearing (p<0.02), and 5mg/kg increased both rearing (p<0.001) and lateral head twitches (p<0.02). Both Cathinone doses decreased the time spent at rest (p<0.001). The number of c-fos immunopositive cells were significantly increased in the striatum (p<0.0001) and suprachiasmatic nucleus (p<0.05) following Cathinone, indicating increased neuronal activity. There was no effect of Cathinone on food intake or body weight.
CONCLUSIONS:
It is concluded that systemic administration of Cathinone induces significant behavioral changes and CNS activation in the hamster. | | Pharmacol Toxicol. 1992 Feb;70(2):77-86. | | Cathinone, a natural amphetamine.[Pubmed: 1508843] | Cathinone is an alkaloid that has been discovered some fifteen years ago in the leaves of the khat bush. This plant grows in East Africa and in southern Arabia, and the inhabitants of these regions frequently chew khat because of its stimulating properties.
METHODS AND RESULTS:
Cathinone, which is S(-)-alpha-aminopropiophenone, was soon found to have a pharmacological profile closely resembling that of amphetamine; indeed, in a wide variety of in vitro and in vivo experiments it was demonstrated that cathinone shares the action of amphetamine on CNS as well as its sympathomimetic effects; thus, for example, drug-conditioned animals will not distinguish between cathinone and amphetamine. These various observations were confirmed by a clinical experiment showing that cathinone also in humans produces amphetamine-like objective and subjective effects. Finally, it was demonstrated that cathinone operates through the same mechanism as amphetamine, i.e. it acts by releasing catecholamines from presynaptic storage sites.
CONCLUSIONS:
Thus, much experimental evidence indicates that cathinone is the main psychoactive constituent of the khat leaf and that, in fact, this alkaloid is a natural amphetamine. | | Br J Clin Pharmacol. 1990 Dec;30(6):825-8. | | Amphetamine-like effects in humans of the khat alkaloid cathinone.[Pubmed: 2288828 ] | 1. The chewing of khat leaves as a stimulant is common in certain countries, and the effects of this material are supposed to be due to the phenylalkylamine alkaloid cathinone.
METHODS AND RESULTS:
In order to determine the effects of this substance in humans, a single oral dose of cathinone or placebo was administered to six healthy male volunteers in a double-blind, random order crossover study. 2. Cathinone produced increases in blood pressure and in heart rate, and these changes were concomitant with the presence of cathinone in blood plasma. 3. The physical and mental changes that the subjects reported during the experiment indicated that cathinone has in humans euphorigenic and psychostimulant effects.
CONCLUSIONS:
4. These observations support the assumption that cathinone is the constituent mainly responsible for the effects of khat, and they show that this alkaloid has also in humans amphetamine-like effects. |
|
Cell. 2018 Jan 11;172(1-2):249-261.e12. doi: 10.1016/j.cell.2017.12.019.IF=36.216(2019)
Cell Metab. 2020 Mar 3;31(3):534-548.e5. doi: 10.1016/j.cmet.2020.01.002.IF=22.415(2019)
Mol Cell. 2017 Nov 16;68(4):673-685.e6. doi: 10.1016/j.molcel.2017.10.022.IF=14.548(2019)
ACS Nano. 2018 Apr 24;12(4): 3385-3396. doi: 10.1021/acsnano.7b08969.IF=13.903(2019)
Nature Plants. 2016 Dec 22;3: 16206. doi: 10.1038/nplants.2016.205.IF=13.297(2019)
Sci Adv. 2018 Oct 24;4(10): eaat6994. doi: 10.1126/sciadv.aat6994.IF=12.804(2019)
