Prostaglandins and related compound prostacyclin, thrombaxanes, leukotrienes and lipoxins are collectively known as eicosanoids. Most are produced from arachidonic acid, a 20 carbon polyunsaturated fatty acid (5,8,11,14-eicosatetraenoic acid). The eicosanoids are considered “local hormones”. They have specific effect on target cells close to their site of formation. They are not secreted from a gland, but rather are created at the time they are needed directly where the problem exists.

1. Presented by
Rashu Raju
M.Pharmacy
Pharmaceutical chemistry
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2. Content
 Introduction
 Distribution
 Nomenclature
 Types
 Pharmacological uses
 Side effects
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3. Introduction
 Prostaglandins and related compound prostacyclin, thrombaxanes,
leukotrienes and lipoxins are collectively known as eicosanoids.
 Most are produced from arachidonic acid, a 20 carbon
polyunsaturated fatty acid (5,8,11,14-eicosatetraenoic acid).
 The eicosanoids are considered “local hormones”.
 They have specific effect on target cells close to their site of
formation.
 They are not secreted from a gland, but rather are created at the time
they are needed directly where the problem exists.
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5. Nomenclature of prostaglandins
 Prostanoic acid (7-[(1s,2s)-2-octylclopentyl] heptanoic acid) is
a saturated fatty acid which contains a cyclopentane ring.
 It is derivatives are prostaglandins- physiologically active lipid
substances.
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6. Types of rings in PGs
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7. Receptors
 PGs, TX act on their own specific receptors located on cell membrane.
 Five families of prostanoid receptors (DP, EP, FP, IP, TP) have been
designated, each after the endogenous PG for which it has been designated
each after the endogenous PG for which it has the greatest affinity.
 All prostanoid receptors are G- protein coupled receptor which can be
functionally categorized
 Excitatory or contractile (EP, FP, TP) and generate IP3- DAG pathway
 Inhibitory or relaxant (DP1, EP2, EP4 & IP) activate cAMP pathway
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9. Types of PGs
PG-D2
Acting on DP receptors
 It causes vasodilatation
 Inhibition of platelets aggregation
 Relaxation of GI & uterine muscles
Side effects
 Asthma
 Low BP
 Clotting time increases
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10. PG-E1 & E2
 Acting on EP 1 receptors
 Broncho constrictor
 GI tract smooth muscle contraction
 Acting on EP 2 receptors
 Broncho dilatation
 GI tract smooth muscle relaxation
 Vasodilatation
 Acting on EP 3 receptors
 Decrease gastric acid secretion
 Increase gastric mucus secretion
 uterus contraction ( in pregnancy)
 GI tract smooth muscles contraction 10
Side effects
 watery diarrhoea
 Diuresis
 Rise the body temperature
 Pain
 Sedation

11. PG-F2
Acting on FP receptors
 Myometrial contraction
 Broncho constriction
 Vasodilatation
 Ocular inflammation
Side effects
 Contraction of uterus
 Dysmenorrhoea
 Asthma
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12. PG-G2 & H2
Acting on DP receptors
 It causes vasodilatation
 Inhibition of platelets
aggregation
 relaxation of GI & uterine
muscles
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13. PG-I
Acting on IP receptors
 Vasodilatation
 Inhibit platelet aggregation
 Broncho dilation
 Hyperalgesic effect.
Side effects
 Diuretic effect
 Fever
 Algesia
 Inflammation
 Clotting time increases
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