2. Prostaglandins & Leukotrienes
DR MUSTANSAR

3. Eicosanoids
The eicosanoids are a group of signaling
sub-stances that arise from the C-20 fatty
acid arachidonic acid and therefore usually
contain 20 C atom (Greek eicosa=20). As
mediators, they influence a large number of
physiological

5. Introduction

Eicosanoids (20 carbons) are found in the animal
kingdom and a variety of plants.

The eicosanoids are oxygenation products of
acid arachidonic (AA) polyunsaturated fatty
acid.

Acid arachidonic is released from membrane by
phospholipase A2 (PLA2).

6. Prostaglandins & Leukotrienes

Local hormones - very active,many functions..

Autacoids from 20 C PUFA
Prostaglandins
Prostacyclin
Thromboxanes
Leukotrienes

7. Functions
 Inflammation
 Smooth
muscle tone
 Blood coagulation
 Reproduction
 GI secretion

8. .
.
SYNTHESI
S
PHOSPHOLIPI
DS
PHOSPHOLIPASE A2
ARACHIDON
IC ACID
CYCLOOXYGENASE
5 LIPOOXYGENASE
LT
A4
PG G2
PGH
ISOMERASE
PGE2
PG
D2
PG F2
2
THROMBOXANE
SYNTHASE
PROSTACYCLINE
SYNTHASE
PG
I2
THROMBOXA
NE A2
LT
B4
LT C4
LT D4

10. Pathways of arachidonic acid (AA) release and
metabolism.

11. .
PHOSPHOLI
PIDS
STEROIDS
PHOSPHOLIPASE A2
NSAIDS
ARACHIDON
IC ACID
CYCLOOXYGENASE
ZILEUTON
5 LIPOOXYGENASE
LT A4
PG G2
PGH2
PGE2
,PG D2
,PG F2
LT B4
THROMBO
XANE A2
PG I2
LT C4
LT D4

12. BIOSYNTHESIS OF PROSTAGLANDINS
 Enzyme
is Cyclo
oxygenase(COX)
COX 1-constitutive.
COX 2-inducible

NSAIDS- Nonselective COX inhibitors.
COXIBS - Selective COX inhibitors
 Aspirin-
Irreversible inhibition of COX
Other NSAIDS- Reversible inhibition

13. Actions
Inflammation
Most important mediators..
Synthesised as per need.
NSAIDS

14. Actions –Smooth muscles
Blood vessels
Pg E2, Prostacycline - vasodilatation
Thromboxane A2 – constriction

15. Prostaglandins

16. Actions :Smooth muscle
Bronchus
PgE2 • BRONCHO
DILATION
PgI2
PgF2α • CONSTRICTI
ON
TXA2
LT

17. Uterus
Both uterus &cervix
Cervical
ripening
Initiation
of Labour
• PgE2
• PgE1
• PgF2

18. Actions
 GIT
MUCUS
HCO3ACID
Natural ulcer protectants..
NSAIDS..

19. 
GIT
Motility
Secretio
n
Cramps
Diarrhoe
a

20. RENAL
PgE2,Prostacyclin -protective..
PgE2,PgI
2
RENAL
VASODILATATI
ON
DIRECT ON TUBULES
RBF
DIURESIS
NATRIURESIS

21. Coagulation
TXA
2
PgI2
PLATELE
TS
AGGREGATIO
N
ENDOTHELI
UM
(-)
AGGREGATION

22. .
Pulmonary
vesselsvasodilatation
EYE-↓IOT
CNSNeurotransmitte
r

23. Clinical Application

Female Reproductive Organ

Male Reproductive System

Inflammation & Immunity

Gastrointestinal Tract

Respiratory System

Musculo skeletal

Cardiovascular

Glaucoma

Kidney

Cancer

25. Preparations & Uses

26. Preparations
Prostaglnd Preparation
in
PgE₁
Misoprostol ,
Alprostadil,Latanoprost
PgE₂
Rioprostil , Enprostil
Dinoprostone
PgF₂α
Prostin
15Methyl
Carboprost / Prostodin
PgF₂α

27. Uses
1.Obstetrics
Therapeutic abortion
Cervical ripening
PgE1/MISOPROST
OL
PgE₁/PgE2
Severe Post partum hge
15METHYL
PgF2 im/PgE1
Rectal

28. 2.Peptic ulcer
PgE1/Misoprostol
PgE2/Enprostil,Rioprostil,Arbaprostil
3.Glaucoma : PgE1 / Latanoprost
4-PDA
PgE1/Alprostadil
₂
5-Primary pulmonary hypertention : PgI

29. Summary of uses
Use
Abortion
Cervical ripening
Peptic ulcer
Glaucoma
PPH
PDA
Preparation
PgE1
PgE1 / E2
PgE1
PgE1-Latanoprost
PgI2
PgE1

36. ADR
 Vomiting,Diarrhoea,Abdominal
cramps
 Uterine cramps
 Bronchospasm

37. LEUKOTRIENES

38. PHOSPHOLIPIDS
ARACHIDONIC ACID
LIPOOXYGENA
SE
CYCLOOXYGEN
ASE
Zileuton
PROSTAGLANDINS
LEUKOTRIE
NES
LEUKOTRIENE
Monteleuka
RECEPTOR
stZafirleuka
st
Chromoglyca
MAS
te
T
Nedochromil
CELL