This document discusses screening models used to test anti-depressant drugs. It introduces depression, its symptoms, causes and types. It then describes several in vivo and in vitro screening models including the forced swim test, tail suspension test, and tests measuring inhibition of neurotransmitter uptake. The forced swim and tail suspension tests measure how anti-depressants decrease immobility time in rodents. Tests on rat brain and striatum tissues assess drug inhibition of norepinephrine and dopamine uptake. These screening models help determine drug efficacy and potency as anti-depressants.

1. PRESENTED BY: Sanjana SUBMITTED BY: Dr. Saumya
Das
M.PHARMA (PHARMACOLOGY) 1 SEM ASSOCIATE PROFESSOR
PTSM 1 NIET Gr.
Noida
SCREENING MODELS OF ANTI-DEPRESSANTS DRUGS
NOIDA INSTITUTE OF ENGINEERING & TECHNOLOGY
(PHARMACY INSTITUTE)

2. INTRODUCTION ABOUT DEPREESANT
SYMPTOMS OF DEPRESSION
CAUSES
TYPES OF DEPRESSIONS
ANTI DEPRESSANT SCREENING MODELS
TABLE OF CONTENTS

3. INTRODUCTION
• Depression is normally called as a major depressive disorder. It is a mental disorder, in
which the patient is characterised by pervasive and low mood with low self-confidence
and the patient may loss interest in daily life , sad mood, tiredness.etc
• Depression is a feelings of severe despondency and dejection.
• When it is diagnosed, it can be treated and managed easily by therapy and medications.

5. CAUSES OF DEPRESSION

6. CAUSES OF DEPRESSION
GENETICS
A Person with a family history of depression with any close relative are more
prone to have depression if they come under certain circumstances . Many
genes play important role in this.
HARMONAL
Changes in harmone level in males and females can also cause this
disorder. Change in hormonal level during menopause , childbirth can be the
reason. Postpartum depression in mother happens due to hormonal
changes after childbirth.
MEDICATION
S
Some drugs like corticosteroids, isotretinoin , and antivirals like interferon
alpha can causes depression in person taking these medications.

7. DEPRESSION
Bipolar disorder
Persistant
depressive
Disorder
Postpartum depression
Psychotic disorder
Major depression
Seasonal affective
disorder
Situational disorder
Premenstrual
dysphoric disorder

8. PRINCIPLE:-
The basic principle behind testing of anti depressant drugs are to find out the efficacy of the given drug and its effect.
The test can find out how potent the drug is and the dose for anti depressant activity because many drugs in higher or lower doses can give sedative or stimulatory action.
IN- VIVO SCREENIG MODELS-
1. Forced swim test
2. Tail suspension method
3. Learned helplessness in rats
4. Muricide behaviour in rats
5. Amphetamine potentiation test
6. Catalepsy antagonism in chicken
7. Reserpine induced hypothermia
8. Yohimbine toxicity enhancement
ANTI DEPRESSANT SCREENING
MODELS

9. IN-VITRO SCREENING MODELS:-
1. Inhibition of NE uptake in rat brain
2. Inhibition if dopamine uptake in rat striata

10. PRINCIPLE:-
A. It was suggested by porsolt et.al.
B. When rat or mice are subjected to force swim in a limited space with no way to escape then a characteristic immobility develops in them
after some time forced swimming .
C. The anti depressant drugs decrease th eduration of immobility.
PROCEDURE:-
1. Adult rats are allowed to swim in a cylindrical with no escape filled with water at 25 celsius.
2. When the rats are forced to swim in water initially is was hyperactive but approx…5 mins later the activity slow down and the phase of
immobility starts.
3. After 15 mins the rats were removed and allowed to dry . The duration of immobility was measured .
4. The same activity was done for standard and test groups and drugs was administered 1 hour earlier when the test starts.
EVALUATION:
1. The duration of immobility was measured for test, control and standard groups treated with various drugs.
2. The antidepressant drugs decrease the duration of immobility.
FORCED SWIM TEST

11. PRINCIPLE:-
A. When a rat suspended by its tail, the immobility is displayed because of inescapable stress.
PROCEDURE:-
1. Three group of rats are divided and proper food and water are given.
2. Control, test and standard groups are divided and are subjected to respective drugs via intra- paritonial route.
3. The rats are suspended upside down through its tail . At the start of test, the rat try to escape but was unable and become
immobile after some time.
4. The reading were taken for 6 mins by use of CCTV camera and computer and the time for activity and immobility was
recorded and compared with test standard groups.
EVALUATION:-
1. The duration of immobility of standard and test was compared with control groups and decrease in duration was
calculated.
2. For different drugs , ED50 was calculated.
TAIL SUSPENSION TEST

12. PRINCIPLE:-
A. The reuptake of NE is an important physiological process.
B. It is important for removing NE in synaptic cleft .
C. Antidepressant inhibits the reuptake of NE.
D. Hypothalamus is used for this as it has shown great uptake of NE.
PROCEDURE:-
TISSUE PREPRATION
1. Male wistar rats were taken in groups.
2. They were decapitated and their brain are removed rapidly.
3. The hypothalamus is weighed and its preparation is made.
4. Homogenisation of this is done by using ice -cold sucrose solution 0.32M 9 volumes with the help of POTTER- ELVEJHEM HOMOGENIZER.
5. Centrifugation is done at 100g at 0 - 4°C for 10 mins and supernatant is decanted which is used for experiment.
ASSAY
1. 800μl 62.5 Nm NE and 200μl of tissue suspension were mixed and incubated in KREBS-HENSELEIT BICARBONATE BUFFER at temperature
37°C with 20μl test or standard drug or vehicle in control.
Inhibition of NE uptake in rat brain

13. 1. Incubation of each assay tube done at 0°C ice -bath with 20μl vehicle at 95% O2 and 5%CO2 .
2. Centrifugation is done for 10 min at 400g.
3. After that , firstly the supernatant is aspirated and then pellets were dissolved in solublizer .
4. This was shaken and then decanted into SCINTILLATION VIALS.
5. This was counted in 10 ml liquid scintillation counting cocktail.
6. The difference between amp at 37°C and 0°C is the active uptake.
EVALUATION:-
1. The mean of at least three determination is calculated and this is the percent inhibition at each drug
concentration.
2. From log probit analysis IC50 values can be determined.
3. DESIPRAMINE is a standard drug with IC50 value of 20nM.
13

14. PRINCIPLE:-
A. Dopamine has sodium dependent transport of high affinity in various tissue preparation.
B. Dopamine is found in high amount in Stiara.
C. Antidepresssants and cocaine inhibit the uptake of dopamine.
PROCEDURE:-
1. Male wistar rats were taken in groups.
2. They were decapitated and their brain are removed rapidly.
3. The hypothalamus is weighed and its preparation is made.
4. Homogenisation of this is done by using ice -cold sucrose solution 0.32M 9 volumes with the help
POTTER- ELVEJHEM HOMOGENIZER.
5. Centrifugation is done at 100g at 0 - 4°C for 10 mins and supernatant is decanted which is used
for experiment.
ASSAY:-
1. 900μl Nm dopamine and 100μl of tissue suspension were mixed and incubated in KREBS-HENSELEIT
BICARBONATE BUFFER at temperature 37 with 20μl tester standard drug or vehicle in control.
Inhibition if dopamine uptake in rat striata

15. 1. Incubation of each assay tube done at 0°C ice -bath with 20μl vehicle at 95% O2 and 5%CO2 .
2. Centrifugation is done for 10 min at 400g.
3. After that , firstly the supernatant is aspirated and then pellets were dissolved in solublizer .
4. This was shaken and then decanted into SCINTILLATION VIALS.
5. This was counted in 10 ml liquid scintillation counting cocktail.
6. The difference between amp at 37°C and 0°C is the active uptake.
EVALUATION:-
7. The mean of at least three determination is calculated and this is the percent inhibition at each drug
concentration.
8. From log probit analysis IC50 values can be determined.
9. NOMIFENSINE is a standard drug with IC50 value of 460nM.

16. REFRENCE
Tripathi KD, A textbook of essential pharmacology ;5 edition.
https://www.depressiontoolkit.org/aboutyourdiagnosis/depression.asp.
https://www.webmd.com/depression/guide/causes-depression#3

17. THANK YOU