1. MODELING MECHANISMS OF FEAR AND ANXIETY: NICOTINE WITHDRAWAL
AND STRAIN DIFFERENCES
Marissa Applegate, Shruthi Deivasigamani, Conor Driscoll, Sumeet Jain, Sarah McAlister, Jacquelyn Olwell, Ravi Pancholi, Claire Rhee, David Gabriel Rissman, Adam Rosenstein, Madison Taormina, Justin Zhang
Advisors: Dr. Graham Cousens and Zack Vogel

2. Fear vs. Anxiety Fear Anxiety Directed at a stimulus
Dissipates after stimulus is removed
Construct: Phasic Fear
General uneasiness
Long lasting
Construct: Sustained Fear

3. Acoustic Startle Response
Auditory
Input
PNC
Change order of animations
Motor Output

4. Paradigms of Fear and Anxiety
Phasic Fear
Central Nucleus
Anxiety
Sustained Fear
Bed Nucleus of Stria Terminalis (BNST)

5. Acoustic Startle Response
Amygdala
Lateral
Nucleus
Central
Nucleus
BNST
Get rid of cochlear and spinal. Text smaller
Put it in an oval
PNC
Input to PNC to Motor Output
Motor Output
Auditory
Input
PNC

6. Road Map
Experiment 1: Effects of Strain Differences on the Light Enhanced Startle Response in Lewis and Sprague- Dawley Rats
Experiment 2: Effects of Nicotine Withdrawal on Discrete Cue and Contextual Conditioned Fear
Experiment 3: Nicotine Withdrawal-Induced Anxiety in the Elevated Zero Maze
MAKE MORE EXCITING!!!!!!

7. Effects of Strain Differences on the Light Enhanced
Experiment 1
Effects of Strain Differences on the Light Enhanced
Startle Response in Lewis and Sprague-Dawley Rats
Evaluate genetic differences
Measure baseline startle response (1,3)
Light-enhanced startle (LES) (2,4,5)
Impact on future research
Hypotheses – Lewis vs. Sprague-Dawley
Greater baseline startle
Greater percent increase of LES startle response
Sustained fear present after LES
Change last hypothesis
Or prove it.

8. Subjects Experiment 1 Lewis Rat H51-58 8 male Sprague-Dawley Rat
H59-H65
6 male

9. Startle Chamber Experiment 1 +2 A. Coulbourn Precision Animal Shocker
RELABEL
A. Coulbourn Precision Animal Shocker
B. Light
C. Fan
D. Plexiglass cover for inner chamber
E. Odor Emitter
F. Amyl Acetate
G. Outer Chamber
H. Speaker
I. Accelerometer

10. Five minute Acclimation Period
40 pulses at
75, 85, 95, 105 dB
30 seconds apart
Dark
Experiment 1
Light Enhanced Startle
Five minute Acclimation Period
40 pulses at
75, 85, 95, 105 dB
30 seconds apart
Dark
Five minute Acclimation Period
40 pulses at
75, 85, 95, 105 dB
30 seconds apart
Light
Five minute Acclimation Period
40 pulses at
75, 85, 95, 105 dB
30 seconds apart
Dark

11. Baseline Response Experiment 1
The Lewis rats had a higher baseline startle response when compared to the Sprague-Dawleys.

12. Percent Baseline Startle at 95 dB
Experiment 1
Percent Baseline Startle at 95 dB
At the 95 dB level, the Sprague Dawley rats exhibited a higher LES startle response, and a greater percent increase in startle. The Sprague-Dawley also exhibited a sustained fear.

13. Percent Baseline Startle at 105 dB
Experiment 1
Percent Baseline Startle at 105 dB
At the 105 dB level, the Sprague-Dawley rats still exhibited a higher LES reaction and a greater percent increase.

14. Why research withdrawal?
43.5% try to quit smoking
Of those, between 70% and 90% fail (6)
Connection between nicotine withdrawal and anxiety
Treatments to limit withdrawal effects

15. Effects of Nicotine Withdrawal on Contextual Conditioned Fear
Experiment 2
Effects of Nicotine Withdrawal on
Discrete Cue and
Contextual Conditioned Fear
Link between withdrawal and sustained fear
Withdrawal and Phasic Fear
Hypothesis
There will be no effect
on phasic fear.

16. Pavlovian Conditioning
Experiment 2
Pavlovian Conditioning

17. Subjects Experiment 2 + 3 .50 .25 .00 Sprague-Dawley Rat
H1, H2, H3, H8, H9
5 male
High Dosage of Nicotine (.5mg/kg)
Sprague-Dawley Rat
H4, H11, H12, H13, H14
5 male
Low Dosage of Nicotine (.25mg/kg)
Sprague-Dawley Rat
H5, H6, H7, H10
4 male
Control (Saline)
.50
.25
.00
Injected every day for three weeks
Tested two hours after injection

18. Experiment 2
Methods

19. Experiment 2
Previous Results

20. Experiment 2
Results
Conclusion: Robust contextual fear potentiated startle with no difference between groups

21. Experiment 2
Results
Conclusion: No olfactory fear potentiated startle in all groups

22. Nicotine Withdrawal-Induced Anxiety in the Elevated Zero Maze
Experiment 3
Nicotine Withdrawal-Induced
Anxiety in the Elevated Zero Maze
Elevated zero-maze
Nicotine withdrawal leads to anxiety
Elevated zero-maze because rats are afraid of heights; control rats = less anxious… more time in open sections of zero-maze; as anxiety increases, locomotor activity decreases because the rats would be averse to any environmental changes
Hypothesis: As nicotine dosage increases and causes a higher withdrawal affect, anxiety, locomotor activity, and time spent in the closed sections of the maze will increase.

23. Zero Maze Locomotor Activity Experiment 3 Time Spent in Open
and Closed Areas
Walled
Locomotor
Activity

24. Nicotine Withdrawal-Induced Anxiety in the Elevated Zero Maze
Experiment 3
Nicotine Withdrawal-Induced
Anxiety in the Elevated Zero Maze
Nicotine Injections
2 hour waiting period
15 minute testing period
Rat placed in maze

25. Experiment 3
Results
Nicotine dosage had no effect on the amount of time the rats spent in the open sections of the maze.
Nicotine dosage had no effect locomotor activity.

26. Time in Open vs. Time of Day
Experiment 3
Time in Open vs. Time of Day

27. Conclusion Surprising Data Need more conclusive data
Future experiments

28. Acknowledgements Dr. Graham Cousens , who is getting married today!
Dr. Miyamoto, our fearless leader
Myrna Papier, our indispensible organizer
Zack Vogel, our epic counselor
All the NJGSS Staff
And our gracious benefactors:
John and Laura Overdeck
Bayer Healthcare
The Crimmins Family Charitable Foundation
NJGSS Alumni and Parents 1984 – 2011
Bristol-Meyer Squibb
Roche
Kinder Morgan
Bain Capital Childrens Charity
GlastoSmithKline
Novartis

29. Reference Sources Laura Overdeck Bayer
1. Ramos A, Kangerski AL, Basso PF, Da Silva Santos JE, Assreuy J, Vendruscolo LF, Takahashi RN. Evaluation of Lewis and SHR rat strains as a genetic model for the study of anxiety and pain. Behavioral Brain Research Feb; [Internet]. [cited 2011 Jul 27] 129(1-2): Available from:
2. Steiner MA, Lecourt H, Rakotoariniaina A, Jenck F. Favoured genetic background for testing anxiolytics in the fear-potentiated and light-enhanced startle paradigms in the rat. Behavioural Brain Research Aug; [Internet]. [cited 2011 Jul 27] 221(1): Available from:
3. Freet CS, Tesche JD, Tompers DM, Riegel KE, Grigson PS. Lewis rats are more sensitive than Fischer rats to successive negative contrast, but less sensitive to the anxiolytic and appetite-stimulating effects of chlordiazepoxide. Pharmacology, Biochemistry, and Behavior Oct; [Internet]. [cited 2011 Jul 27] 85(2): Available from:
4. Davis M, Walker DL, Miles L, Grillon C. Phasic vs sustained fear in rats and humans: role of the extended amygdala in fear vs anxiety. Neuropsychopharmacology Jan; [Internet]. [cited 2011 Jul 27] 35(1): Available from:
5. Jonkman S, Risbrough VB, Geyer MA, Markou A. Spontaneous nicotine withdrawal potentiates the effects of stress in rats. Neuropsychopharmacology Aug; [Internet]. [cited 2011 Jul 27] 33(9): Available from:
6. (Bronars C, Saul J. Increasing Reach of Tobacco Cessation Quitlines: A Review of the Literature and Promising Practices [home page on the Internet]. Phoenix (AZ): North American Quitline Consortium; [Introduction; cited 2011 July 27]. 18 p. Available from:
Laura Overdeck
Bayer