Transcript Anticonvulsive Effects of Sodium Phenobarbital Experimental purpose

Anticonvulsive Effects of
Sodium Phenobarbital
Experimental purpose


To master the anticonvulsive effects
of sodium phenobarbital and the
elementary process of chi square
test.
To be familiar with the
experimental condition of screening
Anticonvulsants.
 Sedative
and hypnotics are among
the most widely prescribed drugs
worldwide.
 Major therapeutic use is to cause
sedation or encourage sleep. Anxiety
states and sleep disorder are common.
Action and use
 sedative
and hypnotics apt to induce
tolerance and dependence
induce P-450 system
adverse effects are common
 anticonvulsive effects
generalized tonic-clonic seizures
 anesthesia
and preanesthetic
medication
 enhance CNS depression
graded dose-dependent depression of
CNS is a characteristic of sedativehypnotics.
at still higher doses---coma and death
Mechanism
It can activate GABAA receptor,
potentiate GABA action on chloride
entry into the neuron.
The GABAA receptor chloride ion
channel complex has a structure
assembled from five subunits.
Barbiturates
Benzodiazepines
a increase the open time of Cl- channel
b increase the open frequency of Cl- channel
Adverse effect
 drug
hangover: tiredness after awakes
 tolerance: induce P-450 system
 addiction: abrupt withdrawal may cause
tremor, anxiety, weakness, restlessness,
nausea and vomiting
 respiratory depression
 allergy
Poisoning
Poisoning: overdoses can cause death,
depression of respiration and central
cardiovascular depression.
Treatment: artificial respiration;
purging the stomach of its contents;
alkalinization of blood and urine;
hemodialysis
Experimental animals
 Mice
(of either gender), 18~22g
Experimental apparatus
 Mouse
cage
 injector
Experimental drugs
 50mg%
Dimefline ih
 0.4% Sodium Phenobarbital ip
 0.9% Sodium Chloride (Normal
Saline) ip
Experimental indication
 Tetanic
straighten in hind limbs is
positive.
Experimental procedure
 Take
48 mice, weigh them.
 All mice are assigned randomly to
experiment group and control group
according to the principle that equal
weight between groups.
 Students
are divided into twelve
groups, every group takes twe mice
from experiment group and control
group respectively. Mark each mouse,
record the marker in the table.
 Mice
in experiment group are
administered Phenobarbital
intraperitoneal at the dose of
0.5ml/20g. Similarity, mice at the
dose 0.5mg/20g. Similarity, mice in
control group are administered 0.9%
Sodium Chloride intraperitoneal at
the dose of 0.5ml/20g.
 After
30 minutes, each mouse is
administered 50mg% Dimefline
subcutaneously in the dose of
0.5ml/20g.
 After administering Dimefline, we
observe the responds of mice for 30
minutes. If there is convulsive
respond, we need to record it.
 In
the end, all students summary the
results. Record the positive and
negative number in experiment
group and control group in the table.
Analyze and handle the results
 We
analyze the results with chi
square test to see if there is statistical
difference in the percentage of
convulsion between experiment
group and control group.
1. Calculate χ2 value
(1) Calculate χ2 value with basic
formula:
Table 1. Descriptive chart of results
A
Experiment group
Positive number
negtive number
Control groupTotal Positive number
negtive number
total
A: observed value
T: theory value
T
A-T
(A-T)2/T
(2) Calculate χ2 value with
quadruple tabular form:
Table 2. Descriptive chart of results
Experiment group
positive number
negative number
a
c
∑
χ2= (ad-bc)2×n／(a+b) (a+c) (c+d) (b+d)
Control group
b
d
∑
2. Compare the observed value
with theory value to assess if
there is statistical difference.
Question

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What are the methods of making convulsion
model? How to observe drug’s
anticonvulsive effect?
Why anticonvulsive drug be administered
before administering make convulsion drugs
in our experiment?
Which data does the experiment data belong
to? Which method we choose to analyze?
How to do it?