113
7
The pain-relieving properties of opium poppy (Papaver somniferum, . Fig. 7.12) have
been known for millennia. Theriac is a universal remedy dating back to ancient times, and
recipes for this remedy can be found in medical and pharmacological books up to the nineteenth century. Although theriac is much older, it was allegedly the ancient Greek that added
opium to the set of its ingredients (see 7 Box 7.3). Even now, opium poppy is the main commercial source for medically used morphine, codeine and their semisynthetic derivatives.
Opioid receptor
Met-enkephaline
Leu-enkephaline
Codeine
+
Heroin
Morphine
(µ)
(µ)
( µ)
Noscapine
(δ)
Thebaine
Salvinorin A
(κ)
EN D O G E N O U S :
+
+
+
+
+
H
N
H
H
O
O
HO
O
O
O
O
OH
OH
O
O
O
O
O
O
O
O
O
H
N
O
O
O
O
O
O
O
H
O
O
O
O
H
O
NH
NH
HN
HN
N
H
N
H
NH
NH
NH 2
NH 2
OH
OH
S
H
N
H
H
O
O
O
O
H
N
H
H
O
O
HO
HO
H
N
H
O
O
–
. Fig. 7.11 Examples of natural and synthetic compounds that act as agonists and antagonists of the
opioid receptor
7.7 · Opioid Receptor: Morphine/Opiates and Opioids