Laudanosine

Laudanosine
IUPAC name (1S)-1-[(3,4-dimethoxyphenyl)methyl]-6,7-dimethoxy- 2-methyl-3,4-dihydro-1H-isoquinoline
Other names N-Methyl-1,2,3,4-tetrahydropapaverine
Identifiers
CAS number	2688-77-9
PubChem	73397
Properties
Molecular formula	C21H27NO4
Molar mass	357.44 g mol−1
Melting point	89 °C
Y (verify) (what is: Y/N?) Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
Infobox references

Laudanosine or N-methyltetrahydropapaverine is a recognized metabolite^[1] of atracurium and cisatracurium. Laudanosine decreases the seizure threshold, and thus it can induce seizures if present at sufficient threshold concentrations; however such concentrations are unlikely to be produced consequent to chemodegradable metabolism of clinically administered doses of cisatracurium or atracurium.

Laudanosine also occurs naturally in minute amounts (0.1%) in opium, from which it was first isolated in 1871.^[2] Partial dehydrogenation of laudanosine will lead to papaverine, the alkaloid found in the opium poppy plant (Papaver somniferum).

Laudanosine is a benzyltetrahydroisoquinoline alkaloid. It has been shown to interact with GABA receptors, opioid receptors, and nicotinic acetylcholine receptors,^[1][3][4] but not benzodiazepinergic or muscarinic receptors which are also involved in epilepsy and other types of seizures.^[5]

References

1. ^ ^{a b} Fodale V, Santamaria LB (July 2002). "Laudanosine, an atracurium and cisatracurium metabolite". Eur J Anaesthesiol 19 (7): 466–73. PMID 12113608. 
2. ^ Burger A (2005) [1954]. "The Benzylisoquinoline Alkaloids". In Manske RHF, Holmes HL (eds.). The Alkaloids: Chemistry and Physiology. 4. New York: Academic Press. pp. p. 48. ISBN 0124695043. http://books.google.com/books?id=KxTKLlac60wC&pg=PA55&dq=laudanosine&sig=ACfU3U2OZxmvO0Pl8Jnp8KuGXHzMllcnQA#PPA48,M1.  Retrieved September 18, 2008 through Google Book Search.
3. ^ Katz Y, Weizman A, Pick CG, Pasternak GW, Liu L, Fonia O, Gavish M (May 1994). "Interactions between laudanosine, GABA, and opioid subtype receptors: implication for laudanosine seizure activity". Brain Res 646 (2): 235–241. doi:10.1016/0006-8993(94)90084-1. PMID 8069669. 
4. ^ Exley R, Iturriaga-Vásquez P, Lukas RJ, Sher E, Cassels BK, Bermudez I (Sep 2005). "Evaluation of benzyltetrahydroisoquinolines as ligands for neuronal nicotinic acetylcholine receptors". Br J Pharmacol 146 (1): 15–24. doi:10.1038/sj.bjp.0706307. PMC 1576253. PMID 15980871. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1576253. 
5. ^ Katz Y, Gavish M (Jan 1989). "Laudanosine does not displace receptor-specific ligands from the benzodiazepinergic or muscarinic receptors". Anesthesiol 70 (1): 109–111. doi:10.1097/00000542-198901000-00020. PMID 2536252.