Reticuline is a

chemical compound A chemical compound is a chemical substance composed of many identical molecules (or molecular entities) containing atoms from more than one chemical element held together by chemical bonds. A molecule consisting of atoms of only one ele ...

found in a variety of plants including '' Lindera aggregata'', ''

Annona squamosa ''Annona squamosa'' is a small, well-branched tree or shrub from the family Annonaceae that bears edible fruits called sugar-apples or . It tolerates a tropical lowland climate better than its relatives ''Annona reticulata'' and ''Annona cheri ...

'', and ''

Ocotea fasciculata ''Ocotea'' is a genus of flowering plants belonging to the family Lauraceae. Many are evergreen trees with lauroid leaves. There are over 520 species currently accepted within the genus, distributed mostly in tropical and subtropical areas of ...

'' (also known as ''Ocotea duckei''). It is based on the benzylisoquinoline structure. Reticuline is one of the

alkaloid Alkaloids are a class of basic BASIC (Beginners' All-purpose Symbolic Instruction Code) is a family of general-purpose, high-level programming languages designed for ease of use. The original version was created by John G. Kemeny and Th ...

s found in

opium Opium (or poppy tears, scientific name: ''Lachryma papaveris'') is dried latex obtained from the seed capsules of the opium poppy '' Papaver somniferum''. Approximately 12 percent of opium is made up of the analgesic alkaloid morphine, which ...

, and experiments in rodents suggest it possesses potent

central nervous system The central nervous system (CNS) is the part of the nervous system consisting primarily of the brain and spinal cord. The CNS is so named because the brain integrates the received information and coordinates and influences the activity of all p ...

depressing effects. It is the precursor of

morphine Morphine is a strong opiate that is found naturally in opium, a dark brown resin in poppies ('' Papaver somniferum''). It is mainly used as a pain medication, and is also commonly used recreationally, or to make other illicit opioids. Ther ...

and many other alkaloids. It is also toxic to dopaminergic neurons causing a form of atypical parkinsonism known as Guadeloupean Parkinsonism.

Metabolism

3'-hydroxy-N-methyl-(S)-coclaurine 4'-O-methyltransferase uses ''S''-adenosyl methionine and 3'-hydroxy-''N''-methyl-(''S'')-

coclaurine Coclaurine is a nicotinic acetylcholine receptor antagonist which has been isolated from a variety of plant sources including ''Nelumbo nucifera'', '' Sarcopetalum harveyanum'', '' Ocotea duckei'', and others. It belongs to the class of tetrahydr ...

to produce ''S''-adenosylhomocysteine and (''S'')-reticuline. Reticuline oxidase uses (''S'')-reticuline and O₂ to produce (''S'')- scoulerine and H₂O₂. Salutaridine synthase uses (''R'')-reticuline, NADPH, H⁺, and O₂ to produce salutaridine, NADP⁺, and H₂O. Salutaridine can then be transformed progressively to

thebaine Thebaine (paramorphine), also known as codeine methyl enol ether, is an opiate alkaloid, its name coming from the Greek Θῆβαι, '' Thēbai'' (Thebes), an ancient city in Upper Egypt. A minor constituent of opium, thebaine is chemically simil ...

oripavine Oripavine is an opioid and the major metabolite of thebaine. It is the parent compound from which a series of semi-synthetic opioids are derived, which includes the compounds etorphine and buprenorphine. Although its analgesic potency is comp ...

, and

. 1,2-dehydroreticulinium reductase (NADPH) uses (''R'')-reticuline and NADP⁺ to produce 1,2-dehydroreticulinium, NADPH, and H⁺.

References

External links

{{Components of Opium Natural opium alkaloids Phenols Phenol ethers Tetrahydroisoquinolines