Prostaglandins are biologically active lipid compounds derived from fatty acids. The two main prostaglandins, PGE2 and PGF2α, are released during mechanical, chemical, or infectious insults and play a key role in inflammation. They are synthesized from cell membrane phospholipids and have diverse pharmacological actions in various organ systems. Prostaglandins act as vasodilators or vasoconstrictors depending on the tissue, and are involved in processes like uterine contraction, bronchodilation, renal function, and hormone release. Therapeutic uses of prostaglandins include cervical ripening, labor induction, postpartum hemorrhage control, and abortion induction.

1. M.THIRUPPATHI, M.PHARM.,
DEPARTMENT OF PHARMACOLOGY
S.B.COLLEGE OF PHARMACY,
SIVAKASI.
PROSTAGLANDINS

2. INTRODUCTION
 Prostaglandins (PGs) are biologically active
derivatives of 20 carbon atom polyunsaturated
essential fatty acids that are released from cell
membrane phospholipids.
 They are the major lipid derived autacoids.
 They were named so because of their presumed
origin from the prostate gland.
 Human seminal fluid is the richest known source,
but they are also present in various tissues

3.  PGE2 and PGF2 are the two main
prostaglandins. They are released in the body
by mechanical, chemical, and infectious
insults.
 They play an important role in the
development of the inflammatory response in
association with other mediators.

4. BIOSYNTHESIS OF PROSTAGLANDINS

5. CLASSIFICATION OF PROSTAGLANDINS

6. PHARMACOLOGICALACTIONS
Cardiovascular system:
 PGE2 and PGF2α are more potent vasodilators than ACh
or histamine.
 PGF2α constricts many larger veins including pulmonary
vein and artery.
 Fall in BP occurs when PGE2 is injected i.v., but PGF2α
has little effect on BP.
Platelets:
 PGI (prostacycline) is found in the vascular endothelium
and is a potent vasodilator and inhibitor of platelet
aggregation.

7. PHARMACOLOGICALACTIONS
Uterus:
 PGE2 and PGF2 uniformly contract human uterus.
 Dysmenorrhoea in many women is associated with
increased PG synthesis by the endometrium.
Bronchial muscle:
 PGF2α, PGD2 are potent bronchoconstrictors, while
PGE2 is a powerful bronchodilator.
 PGI2 produces mild dilatation. It is used for
asthmatics because PGE2 and PGI2 also inhibit
histamine release and are effective by aerosol.

8. PHARMACOLOGICALACTIONS
GIT:
 They increase intestinal motility.
 PGE inhibits gastric acid secretion and they also stimulate
intestinal fluid secretion, resulting in diarrhoea.
Kidney:
 PGE2 and PGI2 increase water, Na+ and K+ excretion
and have a diuretic effect.
 They cause renal vasodilatation and inhibit tubular
reabsorption.

9. PHARMACOLOGICALACTIONS
CNS:
 Centrally no effective because PGs penetration is
poor into the brain.
Endocrine system
 PGE2 facilitates the release of anterior pituitary
hormones—growth hormone, prolactin, ACTH, FSH
and LH as well as that of insulin and adrenal
steroids.
Eye: PGF2α induces ocular inflammation and lowers
intraocular tension.

10. Adverse Effects: fever, diarrhea, abdominal
cramps, headache, nausea, and vomiting.
Therapeutic uses
1. Cervical ripening and labor induction
2. Control of postpartum hemorrhage,
3. Induction of abortion,
4. Prophylaxis of NSAID-induced peptic ulcers.
5. Recenty used for the treatment of erectile
dysfunction and glaucoma, etc.