Alternatives for animal experiments in teaching

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Alternatives for animal experiments in teaching
Ewen MacDonald Department of Pharmacology
Toxicology University of Kuopio Talk to
Department of Pharmacology /Clinical
Pharmacology University of Turku 6th May 2004
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Alternatives for animal experiments in teaching

• Why do we use animals in teaching?

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Alternatives for animal experiments in teaching
Almost impossible to incorporate into courses
with large numbers of students
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Personal experiences

• Student in Scotland 1967-1971
• Final year pharmacology laboratory exercises
  most afternoons
• Most experiments carried out with isolated organ
  preparations
• First couple of days spent characterizing the
  preparation
• Then the preparation was used to quantify drug
  properties
• Later in the course, the preparation could be
  utilized in the identification of unknown(s)

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Incorporation of simulations into a modern-day
pharmacology method course

• The course is methods in in vitro pharmacology
  for 4th year pharmacy students (n 20 30) and
  consists of
• 10 lectures
• 4 wet-lab experiments (nuclear receptors POP
  enzyme assay catecholamine assay by fluorometry
  pA2 values in isolated rat uterus preparation)
• 3 computer simulation days (many experiments)
• The entire course is 2 study weeks ( 3 ECTS)

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In vitro pharmacology methods course

• Simulations are arranged after the lectures but
  before the wet lab exercises
• Some simulation exercises exactly follow the old
  laboratory schedules
• e.g. determination of pA2 values with the guinea
  pig ileum (though now the actual lab is done with
  rat uterus prep.)

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In vitro pharmacology course

• Other simulations are more complicated and would
  be beyond the capabilities of students (or even
  their instructors)
• determination of alpha2/alpha1-selectivity ratio
  of antagonists in vas deferens
• determination of unknown compound chosen by the
  programme

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Guinea pig ileum preparation

• This simulation was designed in University of
  Strathclyde, Scotland by Dr. Chris Prior.
• Later in the course we do the actual experiment
  using acetylcholine as the agonist and atropine
  as the antagonist
• This can be viewed as a practice run for that
  exercise.

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Guinea pig ileum preparation
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Guinea pig ileum preparation
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Guinea pig ileum preparation
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Guinea pig ileum preparation

• Advantages
• Its free of charge (though you may have to ask
  Chris Prior personally) (http//spider.science.str
  ath.ac.uk/physpharm/)
• Its simple to use
• Results as traces or in tabular form
• It is an excellent introduction to simulated
  experiments

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Guinea pig ileum preparation

• Disadvantages
• Limited number of choices agonists are either
  acetylcholine or histamine antagonists are
  atropine or mepyramine.
• It is not very realistic

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Other free simulations from Strathclyde
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Virtual cat
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Virtual cat
Unknown drugs A- Q Do not need to use all of the
options
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Virtual rat
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Strathclyde preparations - comments

• These are newly revised the older versions were
  less suitable for our students
• The new versions do seem to be extremely
  versatile and the programming flaws in the
  earlier versions have been eliminated
• Overall suitable for advanced students

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Other virtual preparations used in Kuopio

• Hemi-diaphragm
• Vas deferens
• These are prepared by Dr. Ian Hughes (PIDATA,
  University of Leeds)
• They can be purchased for a reasonable charge
  (about 420)
• Each preparation is used for at least two three
  hour sessions

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The phrenic nerve - hemidiaphragm computer
simulation
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The simulated isolated vas deferens preparation
part of the material provided prior to exercise
for the students

• This computer simulation was created by Dr. Ian
  Hughes University of Leeds, England.
• We will use it in three experiments
• 1) examination of the adrenergic receptors
  present in the vas deferens
• 2) examination of how cocaine alters the
  sensitivity of adrenergic agonists

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The simulated isolated vas deferens preparation

• 3) Determination of the alpha-2/alpha-1
  selectivity ratio of an antagonist
• This experiment will only be done if we have at
  least one hour before the end of the class

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The simulated isolated vas deferens preparation
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The simulated isolated vas deferens preparation
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The simulated isolated vas deferens preparation
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The simulated isolated vas deferens preparation
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The simulated isolated vas deferens preparation

• These are the agonists we will examine in the
  first part of the experiment
• Noradrenaline (alpha-1 alpha-2 beta-1/2)
• Phenylephrine (alpha-1)
• Azepexole (alpha-2)
• Isoprenaline (beta-1/beta-2)
• Salbutamol (beta-2)

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Experiment 1 - Characterise which receptors are
involved in the response of noradrenaline

• You have access to several blocking drugs
• Prazosin (potent alpha-1-blocker acts in the
  nanomolar range)
• Idazoxan (potent alpha-2-blocker acts in the
  nanomolar range)
• Propranolol (potent beta-blocker acts in the
  nanomolar range)

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Experiment 1 - Characterise which receptors are
involved in the response of noradrenaline

• Select positive control responses for the three
  adrenoceptors with azepexole phenylephrine
  salbutamol and a suitable dose of noradrenaline
• Examine how these change in the presence of the
  antagonist
• You will know the antagonist is working when it
  blocks its corresponding agonist

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Experiment 1 - Characterise which receptors are
involved in the response of noradrenaline
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Experiment 1 - Characterise which receptors are
involved in the response of noradrenaline

• In your lab report decide which receptor is
  involved predominantly in the response to
  noradrenaline.
• Explain how you came to your conclusion

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Experiment 2 - Compare the potencies of
noradrenaline and phenylephrine

• In this part of the experiment, we want to
  compare two drug noradrenaline and
  phenylephrine. Both drugs can activate
  alpha-1-adrenoceptors. The difference is that
  noradrenaline is non-specific, it activates also
  alpha-2- (and to a lesser extent also beta-2)
  adrenoceptors

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Experiment 2 - Compare the potencies of
noradrenaline and phenylephrine

• Therefore, if we wish to compare these two drugs
  we must do our dose-response evaluations in the
  presence of adequate concentrations of alpha-2-
  and beta-blockers
• These concentrations should be known from the
  first part of the experiment

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Experiment 2 - Compare the potencies of
noradrenaline and phenylephrine

• Compare the dose response curves of phenylephrine
  and noradrenaline.
• In your lab report state the EC50 values for both
  drugs (concentration causing 50 of maximum
  response)
• Were the dose response curves parallel?
• Could you achieve the same maximum effect with
  both drugs?

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Experiment 2 - Compare the potencies of
noradrenaline and phenylephrine

• How much more (or less) potent was phenylephrine
  than noradrenaline?

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Experiment 3 - Compare the potencies of
noradrenaline and phenylephrine in the presence
of cocaine

• One difference between noradrenaline and
  phenylephrine is that noradrenaline is an natural
  catecholamine found in the body, whereas
  phenylephrine is a synthetic drug.
• Cocaine is an effective blocker of the
  noradrenergic uptake system.

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Experiment 3 - Compare the potencies of
noradrenaline and phenylephrine in the presence
of cocaine

• Determine whether the shape of the dose response
  curves obtained in experiment 2 change in the
  presence of cocaine.
• In your lab report explain the reasons for the
  phenomena you have observed

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Experiment 4 - Determination of the
alpha-2/alpha-1 selectivity ratio of an antagonist

• This year it is unlikely that you will have
  enough time to complete this experiment.
• Even in the computer classroom it may take one
  hour or more

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Could / would students do an exercise on their
own time?

• Do you think that you now understand how this
  preparation works to allow you to do the final
  exercise on your own without the help of an
  instructor ? 8 Yes 4 No comment 8 No
• Would you be willing to do the exercise in your
  own time ?
• 5 Yes 3 No comment 12 No

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Simulated Rat Blood Pressure (PIDATA)

• Used in the in vivo pharmacological method course
• Same preparation used in four experiments (on
  four afternoons)
• Day 1 - characterization of preparation
• Day 2 - comparison of pithed normal rats pre
  and post-synaptic alpha-2-adrenoceptors
• Day 3 - apparent pA2 value for yohimbine
• Day 4 - identification of unknown generated by
  programme

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The PIDATA preparations

• Advantages
• They are VERY flexible
• There are many drugs which can be examined
• They are realistic (e.g. if student makes a
  mistake, the preparation will die)
• They are quite well liked by the students

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The PIDATA preparations

• Disadvantages
• They are not so popular as the actual
  preparations
• The PIDATA simulations do not let the students
  print out their results in tabular form
  students have to estimate values from screen
• Moving back through the trace is clumsy
• They do cost something (though in my opinion they
  are good value for money)

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Some other computer simulations
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Some other computer simulations -cLabs
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Some other computer simulations -cLabs
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Comments on cLabs

• Free of charge from Hans Braun (at least I have a
  free copy and Hans is a nice guy!)
• Also contains a voltage clamping simulation
• More suitable for neuroscience students
• Too difficult for pharmacy students

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Microlabs still under preparation,compiled by
Dr. Henk WilgenburgAmsterdam
Parts of the programme are not ready yet e,g.
Drug Discovery) Installation not successful for
other bits e.g. anaesthesia
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Microlabs still under preparationcompiled by
Dr. Henk WilgenburgAmsterdam

• Isolated guinea pig ileum preparation
• Visually much more appealing than the Strathclyde
  version

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Other forms of computer assisted learning
pharma-CAL-ogy
Prepared by UK pharmacologists sold by British
Pharmacology Society (http//www.pharmacalogy.com/
) or via the BPS web site (http//www.bps.ac.uk/bp
s.html) UK government invested over 1 million
pounds in the creation of these computer assisted
learning materials Cover all aspects of
pharmacology, not just experimental techniques
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Other forms of computer assisted learning
pharma-CAL-ogy
Initially departments left students to work their
way through the course material Nowadays being
better incorporated into the courses Supplemented
by teaching and learning resource packs
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Other forms of computer assisted learning
pharma-CAL-ogy
Personal comments More like textbooks than
interactive learning tools Quite expensive for
non-UK users each programme is about 420 One
year rental of 8 programmes licence 500
Rather brief students could work their way
through the entire ion channel material in about
40 minutes Some parts of the programme are
suitable for second year students, other parts
for more advanced students Inflexible cannot be
edited
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How to avoid wasting money

• Computer assisted learning programmes are not
  always inexpensive
• If possible, try to examine the programme
  yourself before you purchase it
• Other options
• Read the EURCA reviews
• Borrow it first from InterNiche

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Information on computer programmessuitable for
pharmacology courseshttp//www.eurca.org
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Reusable learning objectives

• The EURCA consortium has applied to the EU
  Socrates programme for funding for the creation
  of a library (or repository) of reusable
  teaching / learning modules (simulations, movies,
  pictures, multiple choice questions, powerpoint
  slides etc.)
• Teachers can mixnmatch (i.e. take exactly what
  they need, add text in their own language etc.)
• Funding decision in September 2004

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Conclusions - what do simulations fail to teach?

• Experimental technique if it is important that
  your students gain hands-on experience of
  experimental techniques (for example how to set
  up a guinea-pig ileum preparation how to
  cannulate a blood vessel etc.) then you cannot
  rely exclusively on simulations
• Even in these cases, simulations may be very
  useful introductions to the actual laboratory
  class
• But how many students truly need these skills?

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Conclusions - where simulations are useful

• Giving a student a taste of experimental
  pharmacology
• Showing in theory how drugs act on
  pharmacological preparations
• Generating realistic data to allow the students
  to calculate important drug-related parameters
  (pA2 values etc.)
• Encouraging students to devise experiments to
  test hypotheses
• Developing group working skills