Corynanthine, also known as rauhimbine, is an

alkaloid Alkaloids are a class of basic, naturally occurring organic compounds that contain at least one nitrogen atom. This group also includes some related compounds with neutral and even weakly acidic properties. Some synthetic compounds of similar ...

found in the '' Rauvolfia'' and '' Corynanthe'' (including ''Pausinystalia'') genera of plants. It is one of the two

diastereoisomer In stereochemistry, diastereomers (sometimes called diastereoisomers) are a type of stereoisomer. Diastereomers are defined as non-mirror image, non-identical stereoisomers. Hence, they occur when two or more stereoisomers of a compound have dif ...

s of

yohimbine Yohimbine (), also known as quebrachine, is an indole alkaloid derived from the bark of the African tree '' Pausinystalia johimbe''; also from the bark of the unrelated South American tree ''Aspidosperma quebracho-blanco''. Yohimbine is an α2 ...

, the other being

rauwolscine Rauwolscine, also known as isoyohimbine, α-yohimbine, and corynanthidine, is an alkaloid found in various species within the genera ''Rauvolfia'' and ''Corynanthe'' (including ''Pausinystalia''). It is a stereoisomer of yohimbine. Rauwolscine is ...

. It is also related to

ajmalicine Ajmalicine, also known as δ-yohimbine or raubasine, is an antihypertensive drug used in the treatment of high blood pressure. It has been marketed under numerous brand names including Card-Lamuran, Circolene, Cristanyl, Duxil, Duxor, Hydroxysarp ...

. Corynanthine acts as an α₁-adrenergic and α₂-adrenergic receptor antagonist with approximately 10-fold selectivity for the former site over the latter. This is in contrast to yohimbine and rauwolscine which have around 30-fold higher affinity for the α₂-adrenergic receptor over the α₁-adrenergic receptor. As a result, corynanthine is not a stimulant (or an

aphrodisiac An aphrodisiac is a substance that increases sexual desire, sexual attraction, sexual pleasure, or sexual behavior. Substances range from a variety of plants, spices, foods, and synthetic chemicals. Natural aphrodisiacs like cannabis or cocai ...

for that matter), but a

depressant A depressant, or central depressant, is a drug that lowers neurotransmission levels, which is to depress or reduce arousal or stimulation, in various areas of the brain. Depressants are also colloquially referred to as downers as they lower the ...

, and likely plays a role in the antihypertensive properties of ''Rauvolfia'' extracts. Like yohimbine and rauwolscine, corynanthine has also been shown to possess some activity at serotonin receptors.

References

{{Serotonin receptor modulators Alkaloids found in Rauvolfia Alpha-1 blockers Alpha-2 blockers Antihypertensive agents Tryptamine alkaloids Indoloquinolizines Quinolizidine alkaloids

See also

References