1. The document summarizes research on the 5-HT2A serotonin receptor and its interaction with the hallucinogenic drug LSD. It discusses the structure of serotonin receptors and the 5-HT2A receptor specifically. 2. Molecular modeling and simulations have been used to study the 5-HT2A receptor since its exact structure is unknown. These suggest ligand binding causes shifts in the receptor's transmembrane helices that tighten the binding site. 3. Key interactions between LSD and the 5-HT2A receptor are thought to involve hydrogen bonding between the ligand's N-benzyl group and a tyrosine residue on the receptor.

1. 1
Structural and Functional Exploration of 5-HT2A and its
Response to Lysergic Acid Diethylamide (LSD)
Laura Glastra
Chemistry Department, Pacific Lutheran University, Tacoma WA 98477, USA
INTRODUCTION
Serotonin receptors are a class of G-protein coupled receptors (GPCRs). These serotonin
receptors are located in regions of the brain related to the visual cortex, limbic system,
basal ganglia, and olfactory nuclei (Frazer et al., 1999). The actions of different GPCRs
vary based on amino acid sequences and protein structures, which interact differently
based on the specific ligand. Ligands such as hallucinogens effect a wide range of
receptors including the majority of the serotonin family. The most potent known
hallucinogen, lysergic acid diethylamide (LSD), has a high affinity for the 2A serotonin
receptor (5-HT2A) (Nichols, 2012). LSD’s hallucinogenic effects would not be possible
without the 5-HT2A receptor, but the exact mechanism of action has not yet been
discovered. The following review is the product of extensive research into the various
known mechanisms that are involved in the binding and action of LSD with the 5-HT2A
receptor.
BACKGROUND
Serotonin, or 5-hydroxytryptamine (5-
HT), is a neurotransmitter derived from
the amino acid tryptophan (Nichols et
al., 2001) (Figure 1). It is found in the
brains of various organisms from
nematodes such as C. elegans to
vertebrates (Nichols et al., 2001). Its
function varies between organisms, and
in C. elegans it is responsible for egg
laying and other relatively simple
behaviors (Nichols et al., 2001). This
evolution history suggest that the
receptor is highly conserved. The focus
of this review will be on the action of the
human receptor. In humans, 5-HT is
involved with more complex behaviors
like sleep cycle, mood, and memory
(Nichols et al., 2001). Serotonin
neurons within vertebrates are all found

2. 2
throughout the raphe nuclei (RN)
(Nichols et al., 2001).
5-HT is an inhibitory transmitter that is
produced by neurons within the RN of
the midbrain (Nichols et al., 2001). The
RN branch from the brainstem and can
be found throughout the majority of the
brain (Nichols et al., 2001). It is thought
that the neurons located here may be
involved in inhibitory processes that
prevent the brain from overstimulation
(Nichols et al., 2001). When the activity
or production of 5-HT decreases it is no
longer effective at inhibiting other
neurons in the reaction chain (Nichols et
al., 2001). This results in the brain
becoming increasingly more active
(Nichols et al., 2001).
There are seven families, or groups, of
serotonin receptors ranging from 5-HT1
to 5-HT7 (Frazer et al., 1999). Of these
families of serotonin receptors, the 5-
HT1A, 5-HT1B, 5-HT1C, 5-HT1D, and 5-
HT2 belong to the G-protein receptor
superfamily (Frazer et al., 1999). Each of
these 5-HT families is a single-subunit
protein receptor (Frazer et al., 1999).
The 5-HT2A receptor is influenced by a
variety of hallucinogenic drugs (Nichols
et al., 2001). The effect of hallucinogenic
drugs would not be possible without the
5-HT2A receptor (Nichols et al., 2001).
The potency of hallucinogens can
therefore be determined by their affinity
for the 5-HT2A receptor (Nichols et al.,
2001).
The 5-HT2A receptor is highly
concentrated in the prefrontal cortex
and other areas of the brain’s cortical
regions (Frazer et al., 1999). Cortical
regions of the brain include the
claustrum which is connected to the
visual cortex, the limbic system involved
in the endocrine and autonomic nervous
system, which are involved in emotion,
learning, and memory function; the
basal ganglia that is responsible for
habit based learning and motor
behaviors, and the olfactory nuclei,
which are highly evolved in vertebrates
and are involved with odor information
processing (Frazer et al., 1999).
There are primarily three types of
chemicals that act as agonists for the 5-
HT2A receptor. These include
tryptamines, ergolines, and
phenethylamines (Figure 1).
Tryptamines are the agonists most
closely related to serotonin, which is the
natural neurotransmitter. Ergolines are

3. 3
tetracyclic molecules derived from
alkaloids in ergot fungus. An example of
such a molecule, the most potent of the
known psychedelics, is lysergic acid
diethylamide (LSD) (Nichols, 2012).
Some studies have proposed the
following to explain the general
mechanism of LSD’s effects on
serotonin:
In view of the localization of the
raphe nuclei close to the brain
stem’s consciousness-alerting
system, called the ascending
reticular activating system
(ARAS), it is suggested that LSD
could influence the gating
function of this system for
afferent sensory information.
Thus a reduction in serotonin
release mediated by inhibitory
presynaptic serotonin receptors
would be likely to reduce the
tonic inhibition in the ARAS due
to serotonin and thus allow
abnormal stimulation of the
visual and other relevant areas of
the brain, causing hallucination
(Bradford et al., 1986).
Structure of LSD.
LSD is a relatively planar molecule with
a molecular mass of 323 g/mol and
chirality at two positions in the molecule
(Nichols, 2012). These chiral centers are
at carbons 5 and 8, which have strong
influence over the psychoactive
properties of the molecule (Figure 2).
The carbons must be in a 5R, 8R -
configuration for LSD to be biologically
active. This relationship of configuration
and biological activity is seen
throughout all ergolines (Nichols, 2012).
There are many non-psychoactive forms
of LSD, however little research has been
done in clinical settings with the
exceptions of those that occurred in the
1950s and 1960s prior to the legal
changes that occurred in that 1970s.
These studies found that the
psychoactive and biologically active
properties of LSD change in response to
reduction of double bonds,
halogenation, and alkylation (Figure 2).
The (+)-LSD or d-LSD form is the
psychoactive form that had previously
been used for therapy. Epimerization of
LSD readily occurs at the 8-position,
producing (+)-isolysergic acid
diethylamide (Figure 2). This isomer is
not an active hallucinogen, further
supporting the importance of the

4. 4
specific configuration required at the 5
and 8 chiral carbons (Nichols, 2012).
Halogenating the 2-position of LSD
resulted in molecules that acted as
antagonists of the 5-HT2A receptor,
rather than agonists such as (+)-LSD
(Figure 2). Antagonists such as these
molecules act to inhibit binding of
serotonin (Nichols, 2012).
Reduction of the 9,10-double bond was
another alteration made to LSD in early
research (Figure 2). This reduction also
removed the hallucinogenic activity of
the molecule. In tryptamines, similar
reductions of the highest pi-bond
orbitals did not have the same effect on
hallucinogenic activity. This signifies
that the 9,10-double bond is an
important characteristic of the
molecule’s psychoactive properties,
though it is unclear why (Nichols, D. E).
A reduction of the 2,3-double bond was
also conducted, and the molecule
remained biologically active afterwards
(Figure 2). The onset of the psychoactive
effects were slower, however, suggesting
that metabolic changes may alter the
conformation of the molecule in the
body. Hallucinogenic effects were still
reported, though it was found to be
approximately eight times less intense
than LSD itself (Nichols, 2012). This
reduction occurs on the indole group of
the LSD molecule. Some studies have
suggested that this functional group is a
distinguishing factor on how various
psychedelics function. LSD and other
hallucinogens with indole ring systems
preferentially inhibit cells from releasing
serotonin, rather than affecting the
serotonin receptors post synaptic
regulation (Passie, et. al.).
Alkylation of the N(6)-methyl group on
LSD has been found to produce much
more potent psychoactives in vitro
rodent behaviors. It is anticipated that
these effects on rodents are likely to be
comparable to those in humans
(Nichols, 2012).
Serotonin Receptor (5-HT2A)
Structure.
The serotonin receptor has a length of
471 amino acids and a molecular mass of
52,603 g/mol (Figure 3) (UniProt). It is
a G-protein coupled receptor (GPCR),
which stands for guanine nucleotide
triphosphate binding proteins. Of the
GPCR families, serotonin is in the

5. 5
largest, which is the Rhodopsin, or A
Family (Isberg et al., 2011). Previously it
was suggested that receptors produced
intracellular metabolites as a result of
ligand binding, but it is now believed
that GPCRs have the effect they do
because of interactions that occur
between the receptor with the G-protein
(Byrne et al., 2004). Interaction of the
G-protein with its coupled receptor
allows for modulation of different
effector systems such as ion channels,
adenylyl cyclase, and phospholipase C,
which the 5-HT2A receptors activate
(Frazer et al., 1999).
Characteristics of G-proteins include the
presence of seven transmembrane alpha
helices (TM1-TM7), an intracellular
carboxy terminus, and an extracellular
amino terminus. The most conserved
feature of GPCRs is the seven
transmembrane structure (Byrne et al.,
2004, J. H.). Each G-protein complex
has a specific receptor protein that
weaves through the seven
transmembrane segments. It is this
protein’s amino terminus that extends
out of the cell membrane, and its
carboxy terminus that is found inside
the cytoplasm of the cell. Intracellular
loops, or segments, of the protein are
found between TM1 and TM2, TM3 and
TM4, and TM5 and TM6. These
segments are denoted i1, i2, and i3
respectively. The extracellular loops are
connected between TM2 and TM3, TM4
and TM5, and TM6 and TM7. Similarly,
these are denoted as e1, e2, and e3
respectively (Byrne et al., 2004, J. H.)
(Figure 4).
The seven domains that the protein
wraps through are composed of about
24 hydrophobic amino acids. It is in the
center of these proteins where the
binding site is located. Amino acids of
the transmembrane domains point in
toward the binding site. These inward
pointing amino acids influence the
binding affinity of ligands (Byrne et al.,
2004, J. H.). These generalized
structural characteristics describe the
basic structure of the 5-HT2A receptor.
CURRENT RESEARCH
Current research on the 5-HT2A receptor
is limited because the exact structure
has not yet been identified. It has not
been identified exactly because X-ray
crystallography techniques are
especially challenging for membrane
proteins (Rodriguez et al., 2014).

6. 6
Without definitive knowledge of the
protein’s structure, little research has
been able to make conclusions on the
specific molecular function behind the
receptor’s mechanisms. The research
that will be explored in this review focus
on the methodology behind identifying
the structure and why LSD may have
such a high affinity for this receptor.
One approach made in identifying the
structure of 5-HT2A is using 5-HT2A
homology modeling. Homology
modeling begins with use of another
molecule sharing similar characteristics
to the receptor of interest. An inactive
β2-adrenoceptor (β2AR) was used and
then altered to fit characteristics of
active GPCR structures (Isberg et al.,
2011). Alterations to the β2AR were
made to adjust angle positioning of TM5
and TM6, alter the i3 segment sequence
from
LQKIDKSEGRFHVQNLSQVEQDGRTG
HGLRRSSKFCLK to AQQQESATTQKA,
insert a Gαs peptide backbone, and move
R1313.50 to a rotamer with interaction of
the G-protein (Figure 5) (Isberg et al.,
2011).
Models of 5-HT2A have been produced in
silico through steered molecular
dynamics simulations (Isberg et al.,
2011). Since structure of the receptor is
unknown, the model was steered
towards a structure that fit the
characteristics of known GPCRs.
Specific distance constraints were set for
bond lengths based on X-ray
crystallography and mutagenesis data.
These were included in the
simulations as pairwise (donor -
acceptor) atom distance
harmonic constraints (default
between hydrogen and acceptor:
1.8 Ǟ; G-protein and helix 8: 2.2
Ǟ; protonated nitrogen in ligand
and - D1553.32 gamma carbon: 3.0
Ǟ (Isberg et al., 2011).
These binding characteristics lead to
movement of helices and side-chains
energy changes. These changes are
thought to continue until the active form
of the molecule is achieved (Isberg et al.,
2011). In silico studies demonstrate the
importance of side-chain rotameric
actions. Change in rotameric position is
referred to as a “toggle switch”
(Tautermann et al., 2011). Toggling can
occur strongly in response to activation

7. 7
by agonists while the binding site holds
a similar conformation in the active and
inactive state (Tautermann et al., 2011).
Constraints imposed in the silico
modeling method include the
aforementioned binding lengths, ligand-
receptor binding, G-protein-receptor
binding, interhelical receptor binding,
and helical backbone binding of the
receptor and G-protein to prevent local
distortions and unfolding at truncated
sites (Isberg et al., 2011). Hydrogen
bonding was a key restriction emplaced
to stabilize hydrophobic networks
throughout the helices. These
constraints were imposed to activate the
receptor models.
Extracellular Face and Ligand
Binding Site.
Helical shifts induce tightening of the
overall binding site inside of the helices.
Tightening is required for proper
binding of the ligand to occur because of
the proximity and arrangement of the
ligand and receptor complex. (Isberg et
al., 2011; Shapiro et al., 2002). Changes
in proximity of the ligand and binding
site interactions occur because of side
chain rotations, helical tilting, and
helical rotating. The main observed
cause leading to activation of the
receptor occurs due to the rotations in
the side chains (Isberg et al., 2011). The
largest movements observed through the
molecular dynamics modeling occurred
when constraints were first
implemented and when the restraints of
the helical backbone were released
(Isberg et al., 2011).
The largest known movement of the
extracellular surface is an inward tilt of
TM6. Another movement is the shift of
TM3 moving closer to TM5 (Isberg et al.,
2011). Additionally, TM7 shifts to the
side toward TM1, likely occurring as a
response to make room for the
repositioning of TM6. As a result of the
TM7 shift, TM 1 and TM2 both shift
sideways as well. The shift of TM7 is
away from the ligand binding site, but
the helix maintains good hydrogen
bonding with N-benzyl groups of the
ligand. It is thought to be a tyrosine
molecule that induces hydrogen bonding
with the N-benzyl moiety (Isberg et al.,
2011).
The TM6 helix also has significant
interactions with the TM3 helix through
strong ionic forces (Shapiro et al.,
2002). Changes in movement of TM6

8. 8
are proposed to be a result of the
interaction the helix has during the
binding of the agonist (Shapiro et al.,
2002). This hypothesis has been tested
through site directed mutagenesis and
molecular modeling. This interaction
may proceed via aromatic residues of
TM6. The interactions and movement of
TM6 lead to disruptions in ionic
bonding between it and the TM3 helix.
This is hypothesized to be a wide
ranging interaction of agonist bound 5-
HT receptors that are coupled to G-
proteins given the similarities in amino
acid sequences of 5-HT receptors
(Shapiro et al., 2002).
It is possible these interactions are
through the side chains of the TM6
helix’s hydrophobic residues (Shapiro et
al., 2002). The TM6 helix has three
hydrophobic regions composed of
different combinations of cysteine,
arginine, isoleucine, leucine,
phenylalanine, tyrosine, valine, and
asparagine. Alanine substitution in these
three regions induces strong Van der
Waals forces with adjacent helices
through their residues (Shapiro et al.,
2002).
The ionic and hydrophobic interactions
that occur through residues within the
TM6 helix have key stabilizing effects for
the inactive 5-HT2A receptor (Shapiro et
al., 2002). When agonist binding occurs,
TM6 does not maintain its stabilizing
properties, and activation of the
receptor begins.
Side chain interactions are important
because of changes in hydrogen bonding
that can have drastic effects on the
molecular functions and interactions
with other side chains and helices
(Shapiro et al., 2002).
Intracellular Face and G-Protein
Binding Site.
TM6 is also involved in the intracellular,
or cytoplasmic, movements of the
receptor (Figure 6). To make room for
the G-protein the TM6 shifts outward,
which is an example of the “global
toggle-switch method.” In order for the
TM6 movement to occur, the TM5
moves sideward to provide space. This
mechanism may not be universal to
GPCRs since different interprotein
interactions occur through differences in
receptor sequences (Isberg et al., 2011).

9. 9
The intracellular loop i2 may be
involved in specific binding reactions of
hallucinogenic and non-hallucinogenic
drugs (Figure 4). Implications of this
involve different pharmacological
actions of the receptor based on the
specific hallucinogen (Perez-Aguilar et
al., 2014). The global toggle-switch
model is a proposed method for the
different functional mechanisms that
occur with the i2 loop and different
ligands.
CONCLUSION
In summary, 5-HT2A is G-protein
coupled receptor. It is characterized by
seven transmembrane helices (TM1-
TM7) as well as extracellular and
intracellular loops. Each helix and loop
interact with the binding ligand, but
some do more than others. The TM6
helix in particular has many effects that
result in changes of other helices as well.
This includes TM5 and TM3.
Various methods have been used to
attempt construction of the protein’s
structure, but this has proved extremely
difficult. It is a membrane-bound
protein, which are challenging to
crystallize. Modern techniques have
shifted towards molecular dynamics
modeling. These have provided
relatively accurate models based off of
ligand binding tests conducted in the
studies. One challenge remaining is
determining individual interactions of
internal amino acids with the ligand
when binding in the active site. The
knowledge behind this mechanism for
LSD would provide insight as to why a
molecule with relatively similar traits to
serotonin has as high of an affinity as it
does for the 5-HT2A receptor.
ACKKNOWLEDGMENTS
The author thanks Dr. Tonn for her
support and guidance in this research as
well as providing the CHEM403 student
body with the opportunity to conduct
their own choices of research. Additional
thanks are attributed to Pacific Lutheran
University for access to journal articles
and other resources. Finally, it is of
great appreciation to the authors cited in
this review for their dedication and
efforts to furthering the knowledge of
the scientific community and general
population.

10. 10
FIGURES
Figure 1. Structures of various types of agonists on the 5-HT2A receptor. There are
similarities between tryptamines and ergolines, though tryptamines tend to have more
similar binding characteristics as serotonin given similarities of the indole ring structure
and amine groups (Nichols, 2012).
Figure 2.
Structures of lysergic acid diethylamide (LSD). The key characteristic is the indole ring,
which is similar to serotonin’s structure and an important part of the molecule involved
in the binding to the active site (Wikimedia Commons).

11. 11
Figure 3. Represented is the “canonical” sequence of the 5-HT2A receptor, with a length
of 471 amino acids and a molecular mass of 52, 603 g/mol (UniProt).
Figure 4. General structure for a G-protein coupled receptor, where purple circles
indicate conserved amino acids throughout the entire G-protein family. The protein
displayed is mAChR in its M3 isoform. The diagram provides the general structural
characteristics of G-proteins, where there are seven intermembrane helices, an
extracellular amino terminus, and an intracellular carboxy terminus. The second
diagram consisting of parts A, B, and C shows the seven transmembrane domains with
the center as the binding site. These are not the structure for the 5-HT2A receptor, but it
displays a generalized formation of how the ligand binds in the active site. Displayed
here is a catecholamine binding in βAR. This model also demonstrates the stabilizing
hydroxyl groups within the active site (Byrne et al., 2004).

12. 12
Figure 5. Extracellular view of the transmembrane helices involved in the 5-HT2A
receptor. The magenta shows the structure of β2AR while the brown depicts the 5-HT2A
receptor modeled through molecular dynamics. Tightening of the helices is the most
important function involved in binding of the active site. This involves transmembrane
helices 3, 5 and 6. Changes to the TM5 and TM6 present in this figure were made during
the molecular dynamics modeling (Isberg et al., 2011).
NH2
T
T
T
T
T
T
T
T
T
T
T
T
T T
T
T
T
T
T
T
T
T
T
T
T
T
T
T
M
– – L
G
G
G
G
G
G
G
G
G
G
GH
W
W
W
Q Q
Q
V
VF
F
F
F
F
F
F F
F
F
F
F
F
F
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
V
V
V
V
V
V
V
V
V
V
V
V
V
V
V
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V
V
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I I
I
K
K
K
K
K
K
K
K
K
K
K
K
K
K
K
L
L
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L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
N
N
R
N
N
N
N
M
M
M
M
M
M
M
N
N N
N
N
N
N
N
Y
Y
Y
Y
Y
S
S
S
S
S
S
SS
S
S
S
S
S
A
L
C
C
C
113
164
242
140
220
231
502
503
505
529
533
540
143
147
148
Y
Y
Y
Y
Y
Y
Y
Y
Y
R
R
R
R
R
R R
R
R
R
D
L
P
W
W
W
W
W
P
P
P
P
E
E
Q
S–S
E
E
E
—
— — — —
—
—
Q Q
Q
F
F
F
F
F
C
C
C
C
C
D
(COOH)
Intracellular
Extracellular
i1 i2 i3
i4
N-Glycosylation TM1 TM2 TM3 TM4 TM5 TM6 TM7
V
D
D
D
P
P
P
P
N
C
W
W
G
T
FIGURE 11.15 Amino acid sequence and predicted domain topology of the M3 isoform of mAChR. The transmembrane
domains are TM1–TM7. The NH2 terminus of the protein is at the left and extends into the extracellular space. The COOH
terminus is intracellular and is at the right; i1 to i4 are the four intracellular domains. The conserved disulfide bond (–S–S–)
connects extracellular loop 2 to loop 3. The dashes in the amino acid sequence represent inserts of various lengths that are not shown.
Conserved amino acids for all members of the G protein-coupled receptor family of receptors are marked in purple. The amino acids
taking part in ACh binding to the receptor are highlighted in yellow. Note that all amino acids associated with ligand binding lie in
approximately the same horizontal plane across the receptor. Adapted from Trends Pharmacol. Sci., Vol. 14, 1993.
© 2004 Elsevier Inc. All rights reserved.
FROM MOLECULES TO NETWORKS John H. Byrne, James L. Roberts
T234
TM1
TM2
TM3
TM4
TM5
TM6TM7
S-S
C
O
O
H3N
O
H
O
H
-OH
OH
OH
H
O
e2
e3
e4
H3N OH
OH
OH
•••
• • •
• • •
Asp 113
Asp 113 Tyr 329
Ser 207
Ser 204
e2
e3
e4
S - S
i3
i4
A B
C
TM1 TM7 TM6 TM5
TM2 TM3 TM4
OO- +
NH2
NH2
TM1
TM2
TM3
TM4
TM5
TM6TM7
S-S
e2
e3
e4
T231
Y533
Y529
Y506
OH
OH
OH
OH
OHOH
P201
Y148
D147
COO
N
O
+
FIGURE 11.14 (A) Diagram showing the approximate position of the catecholamine binding site in βAR. The transmitter binding site is
formed by amino acids whose side chains extend into the center of the ring produced by the seven transmembrane domains (TM1–TM7).
Note that the binding site exists at a position that places it within the plane of the lipid bilayer. (B) A view looking down on a model of βAR
identifying residues important for ligand binding. The seven transmembrane domains are represented as gray circles labeled TM1 though TM7.
Amino acids composing the extracellular domains are represented as green bars labeled e1 through e4. The disulfide bond (–S–S–) that links e2 to e3
also is shown. Each of the specific residues indicated makes stabilizing contact with the transmitter. (C) A view looking down on a model of mAChR
identifying residues important for ligand binding. Stabilizing contacts, mainly through hydroxyl groups (–OH), are made with the transmitter on four
of the seven transmembrane domains. The chemical nature of the transmitter (i.e., epinephrine versus ACh) determines the type of amino acids necessary
to produce stable interactions in the receptor binding site (compare B and C). Adapted from Strosberg (1990).
© 2004 Elsevier Inc. All rights reserved.
FROM MOLECULES TO NETWORKS John H. Byrne, James L. Roberts

13. 13
Figure 6. Intracellular depiction for the above model of 5-HT2A and β2AR protein
superimposition. (Isberg et al., 2011)

14. 14
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pharmacology of lysergic acid diethylamide: a review. CNS Neuroscience &
Therapeutics 2008, 14, 295-314.
Frazer, A.; Hensler, J. G. Serotonin receptors. In Basic Neurochemistry: Molecular,
Cellular, and Medical Aspects, 6th edition [Online]; Siegel, G. J.; Agranoff, B. W.;
Albers, R. W., et al., Eds; Lippincott-Raven: Philadelphia,
1999. https://www.ncbi.nlm.nih.gov/books/NBK28234/ (Accessed October 20, 2016).
Nichols, C. D.; Sanders-Bush, E. Serotonin receptor signaling and hallucinogenic drug
action. The Heffter Review of Psychedelic Research 2001, 2, 73-79.
Nichols, D. E. Structure-activity relationships of serotonin 5-HT2A agonists. WIREs
Membrane Transport & Signaling 2012, 1, 559-579. doi: 10.1002/wmts.42
Isberg, V.; Balle, T.; Sander, T.; Jørgensen, F. S.; Gloriam, D. E. G-protein and agonist-
bound serotonin 5-HT2A receptor model activated by steered molecular dynamics
simulations. J. Chem. Inf. Model. 2011, 51, 315-325.
Rodriguez, D.; Ranganathan, A.; Carlsson, J. Strategies for improved modeling of
GPCR-drug complexes: blind predictions of serotonin receptors bound to ergotamine. J.
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