This document outlines a study to measure the locomotor activity of mice using an actophotometer. The actophotometer uses photocells to record the number of times a mouse breaks the beam of light, providing a measure of its motor activity. The study will test the effects of diazepam and caffeine on motor activity, with diazepam expected to reduce activity as a CNS depressant and caffeine expected to increase activity as a CNS stimulant. Mice will be injected with each drug and their motor activity measured and compared to baseline. The results will show the percentage change in motor activity caused by each drug.

2. AIM:
TO STUDY THE LOCOMOTER ACTIVIY OF MICE USING
ACTOPHOTOMETER
REFERENCE:
HANDBOOK OF EXPERIMENTAL PHARMACOLOGY BY
S.K.KULKARNI, 3rd EDITION, REPRINT 2007, VALLABH PRAKASHAN
REQUIREMENTS:
INSTRUMENTS: ACTOPHOTOMETER
CHEMICALS: DIAZEPAM, CAFFEINE, SALINE SOLUTION
APPARATUS: SYRINGE, BEAKER,ETC

3. PRINCIPLE
Most of the central nervous system acting drugs influence the
locomotor activities in man and animals. The CNS depressant
drugs such as barbiturates and alcohol reduce the motor activity
while the stimulants such as caffeine and amphetamines increases
the activity. In other words the locomotor activity can be an index
of wakefulness(alertness) of mental activity.
The locomotor activity (horizontal activity) can be easily measured
using an actophotometer which operates on photoelectric cells
which are connected in circuit with a counter when the beam of
light falling on the photocell is cut off by the animal a count is
recorded
An actophotometer could have either circular or square arena in
which the animal moves both rats and mice may be used for testing
in this equipment

4. PROCEDURE:
Weigh the animals and number them
Turn on the equipment (check and make sure that all the
photocells are working for recording)
Place individually each mouse in the activity cage for 10 mins
note the basal activity score of all the animals
Inject diazepam(25mg/kg) and after 30 min retest each mouse
for activity scores for 10 min. Note the difference in the activity
scores before and after diazepam
Same procedure for caffeine(4mg/kg)

5. RESULT
Reduction in the motor activity indicated CNS depressant
property of the drug i.e. diazepam was found to be -------%
Increase in the motor activity indicates CNS stimulant
property of the drug i.e. caffeine was found to be ------%