Effects of Housing Density and Floor Area on Behavior in FST by ISCI8UCB

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									 Effects of Housing Density
and Floor Area on Behavior in
             FST
           Presented by:
           Nadia Proctor
           NSSP Scholar
          Mentor: Dr. Paul
Background Info on Depression

Pathological feeling of sadness
One of the most common psychological
problems
Changes how you think and feel
Affects social behavior and sense of well-
being
17 million American adults/yearly
What is the FST?
          The forced swim test is the most
          widely used pharmacological
          method assessing antidepressant
          activity.
          The test measures the time spent
          in escape-oriented behaviors
          versus the time spent in non-
          escape behaviors a tall cylinder
          filled with water.
          Mice demonstrate three escape-
          oriented behaviors during FST:
          swimming, climbing, and floating.
          Swimming is horizontal
          movement around the beaker or
          from side to side, involving the
          mouse’s forepaws.
          In climbing, the mouse repeatedly
          paws at the walls of the beaker in
          a vertical position.
          Floating is the absence of any
          type of movement.
    Behavioral Effects of FST

Antidepressants reduce the immobility
(floating) time.
Serotonergic-mediated effects increase
swimming behavior (ex. Fluoxetine –
Prozac®)
Noradrenergic-mediated effects increase
climbing behavior (ex. Desipramine -
Norpramin®)
Imipramine (Tofranil®) has both
serotonergic and noradrenergic effects in
the FST.
Housing conditions affect behavior
in the FST

                   200
                                                        Group Housed
Immobility, sec.




                                                        Single Housed
  Duration of




                   150              b
                             a

                   100                       b

                    50

                     0
                         Vehicle   DMI 7.5   DMI 15



Karolewicz and Paul, Eur. J. Pharmacol. 415:197, 2001
            Purpose

This experiment is designed to
determine the effect of elements of
the home environment (housing
density and floor space/mouse) in
response to imipramine in the forced
swim test.
       Materials and Methods

NIH Swiss Webster Mice
Drug - Imipramine (20 mg/kg, i.p.)
2 beakers filled with room temp. (22-26 0C) water
VCR and TV monitor
Horizontal camera
VCR tape
Background (black for white mice)
Experiment label (test numbers on index cards)
Universal Timer program (Infallible Software)
               Procedure
Mice were removed from the colony to the testing
room one hour before experiment.
Two mice were injected with the vehicle (saline) or
drug (imipramine) one hour prior to swim.
Mice were placed individually into water-filled
beakers. A stopwatch was set for 6 min. soon as
the mice entered the water and the room was
exited.
At the end of the six minutes, the mice were
removed from the water and returned to their
cages.
The beakers were emptied, rinsed, and refilled.
The experiment was then repeated.
The tapes of FST were rated using the Universal
Timer program.
              Housing
Mice were housed
in large and small
cages.
1 per large
2 per large
5 per large
1 per small
2 per small
5 per small
         Housing density and floor area
Group Size                                 Number of mice per group
                           Saline                                       IMI (20 mg/kg)

             Large cage       Small cage              Large cage              Small cage

     1               10                    9                   11                           10

     2               10                10                      10                           10

     5               10                10                      10                           10




                                           Floor area (cm2) per mouse
Group Size
                           Saline                                       IMI (20 mg/kg)

             Large cage       Small cage              Large cage               Small cage

     1              1012              504                     1012                          504

     2               506              252                      506                          252

     5               202              101                      202                          101
  Locomotor Activity Testing
Measured in activity
boxes, in which photo
beams measure
locomotion.
This test measures
several elements of
locomotor activity
(ambulation, rearing,
stereotypies).
The LA testing runs for
25 minutes. Data is
collected in 5 min.
intervals.
                     FST Results

                         Floating
           200
                                                L- SAL
                                                L- IMI
                                                S- SAL
Time (s)




                                                S- IMI
           100




            0
                 1   2      5       1   2   5
                FST Results (con’t)

                        Swimming
                                           L -SAL
          250
                                           L- IMI
          200                              S- SAL
                                           S -IMI
Time(s)




          150

          100

          50

           0
                1   2      5   1   2   5
                 FST Results (con’t)

                         Climbing
           150
                                            L- SAL
                                            L- IMI
           100                              S -SAL
Time (s)




                                            S- IMI

           50



            0
                 1   2      5   1   2   5
 Locomotor Activity Results

                           Distance Traveled
                7000
                                                       L- SAL
                6000
                                                        L- IMI
distance (cm)




                5000                                   S- SAL
                4000                                    S- IMI
                3000
                2000
                1000
                  0
                       1     2     5    1      2   5
Locomotor Activity Results (con’t)

                            Vertical Sensor Counts
                     1000
                                                         L- SAL
 movement (counts)




                                                         L- IMI
                     750
                                                         S -SAL
                                                         S -IMI
                     500


                     250


                       0
                            1    2    5    1    2    5
            Summary

Replicated Karolewicz & Paul, 2001
with respect to effects of housing on
control immobility.
Revealed complicated interaction
between cage size and housing
density and, possibly, antidepressant
site of action.
      Further Questions

How does despotic mouse behavior
affect the FST?
Should the dosage of imipramine be
dependent on housing conditions?
              References
Karolewicz and Paul, Group housing of mice
increases immobility and antidepressant sensitivity
in the forced swim and tail suspension tests,
European Journal of Pharmacology 415: 197,
2001
 Detke and Lucki, Detection of serotonergic and
noradrenergic antidepressants in the rat forced
swimming test: the effects of water depth,
European Journal of Pharmacology 73: 43, 1996
Porsolt, Bertin, and Jalfre, “Behavioual Despair” in
Rats and Mice: Strain Differences and the Effects
of Imipramine, European Journal of Pharmacology
51: 291, 1978
     Acknowledgements
Dr. Ian Paul
Dr. Dorota Maciag
Ms. LaShondra Williams
Mr. David Coppinger
Mrs. Tracie Findley
CPN Faculty and Staff
NSSP Scholars
and last but not least…
My little friends
Thank you




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