What is PTSD? PTSD = Post-Traumatic Stress Disorder An anxiety disorder that develops in response to strong stressors Trauma "Incubation" phase (1-6 month)

1/221/22

What is PTSD?

PTSD = Post-Traumatic Stress Disorder

An anxiety disorder that develops in response to strong stressors

Trauma "Incubation" phase(1-6 month)

The development of persistent symptoms

Early responseAcute

Stress Disorder

~1 month

Silent period

2/222/22

DSM-IV criteria for PTSDTriggering factor (Cluster A): traumatic event (1) life threatening (2) helplessReexperiencing the trauma (Cluster B) (1) distressing recollections (2) distressing dreams (3) reliving the experience by illusions, hallucinations, and dissociative flashbacks (4) psychological distress when faced with trauma-related cues (5) psychological distress when faced with trauma-related cuesAvoidance and numbing (Cluster C) (1) avoiding trauma-related thoughts, feelings, or conversations (2) avoiding trauma-related activities, places, or people (3) inability to recall an important aspect of the trauma (4) diminished interest in significant activities (5) detachment from others (6) restricted range of affect (7) sense of a foreshortened futureHyperarousal (Cluster D) (1) sleep problems (2) irritability (3) difficulty concentrating (4) hypervigilance (5) exaggerated startle response Duration is more than 1 month (Cluster E)

Number of symptoms "required" within a cluster2

2

3

2

1

How does it look like? Is it simply anxiety?

It usully lasts years or decades

Trauma(life-threatening stress)

re-experiencing

avoiding cue-associated cues

hyperarousal

+ psychosis depression violence drug addiction anxiety, etc.

A single exposure to a traumatic stress induces a dramatic worsening of in psychological functioning

A remarkable example of neuronal plasticity

3/223/22

Certain profesions (ambulance)

Assaultive violence

Diabetes, children

and in their mothers

and in their mothers

Forced migration

AIDS

Family violence

Trafic accidents, children

Terrorist attack

Natural disaster (earthquake)

Combat

likelyhoodTrauma in mothers, PTSD in child

How important it is? Risk factors and risks

0 10 20 30 40 50 60 70

Prevalence of PTSD (%)

80 90 100

Risk factor

Average

0

2

4

6

8

10

1 2 3 4

Study Nr.5 6 7 8

Pre

vale

nce

of

PT

SD

in

th

e g

ener

al p

op

ula

tio

n (

%)

Prevalence in the general population

Factors prenatal stress early life stress traumatic stressors in adulthood

General perception: People in general are not at risk. I'm safe.

Factors leading to PTSD are parts of daily life

Certain stressors predictably lead to PTSD

similar to the prevalence of other anxiety disorders

Breslau et al., 1991; Breslau et al., 1999; Clohessy and Ehlers, 1999; Creamer et al., 2001; Goowin and Davidson, 2004; Kessler et al., 1995; Landolt et al., 2005; Marshall et al., 2005; Olley et al., 2005; Perkonnig et al., 2000; Resnik et al., 1993; Rosenman, 2002; Seedat et al., 2005; Shalev and Freedman, 20054/224/22

Unemployment

How does it develop? Glutamatergic plasticity

0

100

200

oppo

nent

tim

e (s

ec) 300

0

5

10

Kontroll

cat exposure24 h earlier

0.05 0.1 mg/kg MK-8010open

arm

exp

lora

tion

(%tim

e)

15

*

Adamec et al., 1999Haller et al., 2006

a

Kontroll 0.05 0.1 mg/kg MK-8010

electric shock24 hours earlier

bb

a

Trauma Behavioral deficitsplasticity of

glutamatergic neurotransmission

The blockade of NMDA receptors by MK-801 blocks the development of trauma-related deficits

5/225/22

Treatment

NMDA blockers are highly debilitating and addictive ("angel dust")

Trauma

serotonin

-

SSRIs

-

serotonin

plasticity of

glutamatergic neurotransmission

plasticity of

glutamatergic neurotransmissionBehavioral deficitsBehavioral deficits

alpha 1 or beta blockers

+

noradrenalin

a

b

Sham

c

a

b

0

100

200

oppo

nent

tim

e (s

ec) 300

5-HTx NAx xx

Serotonin and noradrenaline modulate

but not mediatetrauma-induced deficits

Problems with these treatments less well tolerated than placebo efficacy: significant but often poor certain symptoms respond less well effects are often gender-dependent

There are better ways to control

glutamatergic plasticity

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Theory-based approach

Developing a behavioral model

Detailed maping of neuronal activation patterns

Detailed analysis of activated neurons

(e.g. chemotype identification,network analysis, etc.)

Unbiased approach(applied earlier in identifying

the neural backgroundof violent forms of aggression

and proposing NK1 blockers for treatment)

Describing the neuralcontrol of the behavior

in question - new treatment approaches

Testing the theory by behavioral pharmacology

If the theory is right:new treatment approaches

Theory driven approach

Detailed functional maping of cortical networks

Theory on the role of particular neurons

Department of functional and

cellular neuroanatomy(T.F. Freund)

Department of BehavioralNeurobiology

(J. Haller)

Unbiased approach

7/227/22

CB1cannabinoidreceptorok

Calretinincell

CCKbasket

cellParvalbuminbasket cell

GABAA receptorokα2 alegységgel

GABAA receptorsmainly with α1 subunits


M2 muscarinicreceptors

serotonergic

innervation

5-HT3receptors

CCK - Breceptors

The theory: a neuron made for anxiety

CB1cannabinoid

receptors

Nicotinic receptorswith α4 and α7

subunits

Specifically involved in anxiety

8/228/22

CB1cannabinoidreceptorok

Calretinincell

CCKbasket

cellParvalbuminbasket cell

GABAA receptorokα2 alegységgel



M2 muscarinicreceptors

serotonergic

innervation

5-HT3receptors

CCK - Breceptors

Cannabinoid signaling and anxiety

CB1cannabinoid

receptors

Nicotinic receptorswith α4 and α7

subunits

Specifically involved in anxiety

Axon terminal Postsynaptic membrane

GABA

CB1 receptors

GABA

Endocannabinoids

9/229/22

0

10

20

30

40

Ope

n a

rm e

xplo

ratio

n (

% ti

me

)

No changes in locomotion

Testing the hypothesis and ...strange findings with endogenous cannabinoids

WIN-55,212

WT CB1-KO

*

*

AM-251

WT CB1-KO

**

AM+WIN

WT CB1-KO

*

Saline

WT CB1-KO

*

0

10

20

30

40

Ope

n a

rm e

xplo

ratio

n (

% ti

me

)

CD1 mice

Sal Anaminutes

Saline

1 2 3 4 5minutes

Andamide

1 2 3 4 5 Sal Ana

*

mice calledby phone

minutes

Saline

1 2 3 4 5minutes

Andamide

1 2 3 4 5

Subtle changes in endogenous cannabinoid signalling change the response of mice to environmental stimuli

Coward

Brave

10/2210/22

re-experiencing (e.g. exaggerated responses to cues)

avoiding cue-associated cues

hyperarousal (e.g. hypervigilence)

CB1cannabinoid

receptors

Trauma(life-threatening stress)

PTSD and the response to environmental stimuli

Trauma-related deficits are glutamate-dependent

Glutamate receptorsCB1/x receptors

Cannabinoids (i) control the response to stimuli (neurobehavioral evidence)(ii) control glutamatergic discharges (neurophysiological evidence)

Cannabinoids must have a role in PTSD

11/2211/22

0

20

40

60

80

100

1 2 3 4 5 6 7 8 9 10Time (min)

Exp

lora

tion

(%tim

e)

0

20

40

60

80

100

1 2 3 4 5 6 7 8 9 10Time (min)

Res

ting

(%tim

e)

** *

*

0

20

40

60

80

100

1 2 3 4 5 6 7 8 9 10Time (min)

Fre

ezin

g (%

time)

* *o

* **

*

The conditioned fear test as model of PTSD

24 hours

Model of post-traumatic stress disorder

Symptom modelledCluster "B" re-experiencing the trauma by symptom 4 intense psychological distress in response to trauma-associated cues

12/2212/22

0

10

20

30

40

1 2 3 4 5

control

shock

shock AM251 1mg/kg

shock AM251 3mg/kg

fre

ezin

g (

%tim

e)

time (min)

WT-shockWT-control

KO-shockKO-control

fre

ezin

g (

%tim

e)

0

10

20

30

40

1 2 3 4 5time (min)

* **

*

*

#0

20406080

100

control

shock

shock WIN55,212 1mg/kg

fre

ezin

g (

%tim

e)

1 2 3 4 5time (min)

shock WIN55,212 3mg/kg

**

* *

##

# # #

#

0204060

80100

1 2 3 4 5

fre

ezin

g (

%tim

e)

shock

shock WIN03

shock WIN3

shock WIN03AM1

shock WIN3AM1

time (min)

## # #

#

CB1 gene disruptionabolishes conditioned freezing

CB1 blockade slightlydecreases conditioned freezing

CB1 activationincreases conditioned freezing

The antagonist blocksthe effects of the agonist

The interaction between cannabinoid signaling and conditioned fear

0

100

200

300

400

coun

ts

Open-field(mice shocked 24h earlier)

WIN0 WIN03 WIN1 WIN3

AM-251 hadno effect on locomotion

up to 55 mg/kg(literature)

13/2213/22

Cannabinoids and contextual and cue-induced conditioned fear

Contextualconditioned fear

(hippocampus-specific)

Cue-inducedconditioned fear

(amygdala-specific)

Cannabinoids promote theexpression of fear

Cannabinoids promote theextinction of fear

(no effect on expression)

Specificinvolvementin trauma?

Unpecificeffect

(consequence ofmemory-releted

effects)?

Hal

ler

et a

l., 2

006

Marsicano et al., 2002

Different distribution ofCB1 receptors in,

and/or different rolesof cannabinoids in

controlling the,amygdala and hippocampus?

Involvement of other corticalstructures (e.g prefrontal cortex)

in the differential effects?

Cannabinoids promote behavioral dysfunctions induced by traumatic experiencethis appears to be valid for behaviors largely controlled by the hippocampus

Cannabinoids promote the extinction of aversive memoriesthis is apparent in behaviors largely controlled by the amygdala

The involvement of cannabinoids in trauma-related behavioral dysfunctions suggests that cannabinoid signaling is involved in post-traumatic stress disorder

14/2214/22

Interactions between 5-HT3 and CB1 receptors in conditioned fear

5-HT3receptors

CB1cannabinoid

receptors

15/2215/22

The effects of the 5-HT3 agonist mCPBG on anxiety

0

10

20

30

40

Closedentries

% timeopen arms

% openentries

Sal

1 mg/kg

3 mg/kg

10 mg/kg

Elevated plus-maze

Conditioned fear

0

5

10

15

20

25

30

35

1 2 3 4 5 6 7 8 9 10

min

free

zin

g (

% t

ime)

vehicle, no shock

shock, vehicle

shock, 3 mg/kg mCPBG

shock, 10 mg/kg mCPBG

The 5-HT3 agonist does not affect plus-maze anxiety (natural fear)

The same agonist prolongsthe conditioned fear responsewithout affecting amplitude

## # #

#

16/2216/22

Concurrent 5-HT3 agonism and CB1 blockade abolishes conditioned fear

Conditioned fear

0

5

10

15

20

25

30

35

1 2 3 4 5 6 7 8 9 10

min

Fre

ezin

g (

%ti

me) vehicle, no shock

shock, vehicle

shock, mCPBG 3mg/kg

shock, mCPBG 3 mg/kg + AM-251 0.3 mg/kg

shock, mCPBG 3 mg/kg + AM-251 1 mg/kg

0

10

20

30

40

1 2 3 4 5

control

shock

shock AM251 1mg/kg

shock AM251 3mg/kg

fre

ezin

g (

%tim

e)

time (min)

*

*

#

For comparison: the effects of AM-251 ConclusionThere is an unexpectedly strong interaction between mechanisms mediated by 5-HT3 and CB1 receptors, that may be involved inther control of behavioral dysfunctons induced by trauma exposure

Cannabinoids -alone or in combination- are potentially important in the treatment of

trauma-induced behavioral deficits

CCKinterneuron

GABACCK

anxiolytic

anxiogenic

One problem: was the model good enoughto draw this conclusion?

17/2217/22

Despair

Helplessness

Mania

Glucocorticoidexcess

Behavioralsuppression

Etc.

Learnedhelplessness

Forcedswimming

Chronicmild stress

Bulbectomy/open field

Chronicrestraint

Forcedsubmission

Etc.

Anhedonia

The usual way of modeling psychiatric disorders

(1) Tearing symptoms apart (depression is just an example)

(2) Building models for each symptom

(3) Bringing the bits together - theoretical perfection

(3) What often happens in practice

A better solution: modeling the disorder.Is this possible?

This may be feasible in PTSDwhere all symptoms have one single cause:

the trauma

18/2218/22

A symptom by symtom analysis of a PTSD model

"New pharmacological approaches need new behavioral methods"

Traumas employed in the laboratory Electric shocks of various strength, durations, aggravated or not with cue reminders Cat exposure Suffocation stress Restraint + forced swim + halothane or etherBehavioreal deficits investigated Limited number (usually one), often after a limited time interval

Can a complex disorder be modelled simply?

Question asked: can we create a rat in which PTSD can be DIAGNOSED?

19/2219/22



2

3

2

1

0

20

40

60

80

100

**

*

*

Objectmanipulation

Objectburying

% ti

me unshocked, object 1

unshocked object 2

shocked (3 mA) object 1

shocked (3 mA) object 2

300

340

380

420

460

eD mD lD eL mL lL Average

Hea

rt r

ate

eD mD lD eL mL lL Average

1 day before shocks 25 days after shocks

eD= early dark phasemD = mid dark phaselD= late dark phaseeL= early light phasemL = mid light phaselL= late light phase Unshocked control Rats shocked with 3 mA currents

0

20

40

60

80

100

% ti

me

in o

ppon

ent's

cha

mbe

r

unshocked0.8 mA shocks3 mA shocks*

*#

*#

*

1 day after shock

28 days after shock

12Days after shock

0

100

200

300

400 Open field

6 24

Lin

e cr

oss

ing

s (e

xplo

ratio

n) control

3mA 12 Elevated plus-maze1086420C

lose

ed

arm

en

trie

s

* **

**

*

12Days after shock6 24

0

40

80

120

-5 T 5 10 20 30 Average

**

Heart rate changes compared to baseline

minutes

unshocked0.8 mA shocks3 mA shocks

Freezing Escape jumps

**

*

28 days after shock

Freezing Escape jumps

0

20

40

60

80

100

*

*

*Dur

atio

n (%

time)

1 day after shock

unshocked0.8 mA shocks3 mA shocks

Group Freezing(seconds)

Escape jumps(counts)

Vocalizations

duration (sec) latency (sec)

Unshocked control 0.0±0.0 0.0±0.0 0.0±0.0 300±0†

0.8 mA shocks 24.6±6.6* 1.0±1.0 2.5±0.6 76.7±12.8*

3 mA shocks 44.3±15.1* 14.4±6.2*# 8.3±0.3*# 6.8±4.6*#

Deficits seen in rats receiving 10, 1 sec long, 0.8 or 3 mA shocks over 5 min

12days after shock

The duration of the deficits is at least 4 weeksAlso consider the life-span of rats

0

40

80

120

-5 T 5 10 20 30 Average

*

++

++ +

SOC AGO0

5

10

15

20

25

% ti

me

Rez. intr.

*

20/2220/22



2

3

2

1

Can the disorder be modelled as a whole?

Rats shocked with 3 mA currents reach a state that can be considered an animal variant of PTSD

21/2221/22

The next step

Sound theory supported by experimental evidence

Good modelGO!

22/2222/22

Documents

What is PTSD? PTSD = Post-Traumatic Stress Disorder An anxiety disorder that develops in response to strong stressors Trauma "Incubation" phase (1-6 month)