Prepared by Mukesh G Assot professor TRIVENI DENTAL COLLEGE

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2. Adrenergic
systems• Also called sympathetic system ,
• catecholamine's system
• Sympathomimetic drugs
• Adrenomimetic drugs
• Adrenergic agonist
• Adrenoreceptor agonist
• Sympathetic transmission are catecholamine in
nature and it includes – adrenaline ,
noradrenaline , and dopamine secretion.
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3. SYMPATHETIC RESPONSES
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4. SYNTHESIS ,STORAGE ,RELEASE AND UPTAKE
OF ADRENALINE
• All catecholamine are synthesized from amino acid
Phenylalanine in liver then hydrolyzed to tyrosine at
end of nerve.
• Methylation of Nor-adrenaline --adrenaline are
synthesized .
• Tyrosine hydroxylase is rate limiting enzyme and it
inhibited from METYROSINE.
• STORAGE –
• Noradrenaline stored in synaptic vesicles or
granules within the sympathetic nerve ending . On
methylation in cytoplasm NE convert into
adrenaline in adrenal medulla.24-04-18 18:28 4

5. • PHENYLALANINE
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TYROSINE
DOPA
DOPAMINE
NOR-ADRENALINE ADRENALINE
Hydroxylase
Tyrosine hydroxylase
Decarboxylase
Beta-hydroxylase
Methyltransferase
In liver
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6. • Release –by nerve impulse and indirectly by
amines pumps.
• Uptake of CA s – that is recaptured by two ways
– 1) Axonal uptake – amine pump works to
recaptured the NA and Adr in syneptic junction.
NET present at neuronal memmbrane. This uptake
inhibited by cocaine, desipiramine ,guanathidine
and many H1-antihistaminic drugs.
• 2) Granular uptake- Intracellular amino pump
which transport CA from cytoplasm to within
granules . This pump help in recaptured the NA
from axoplasm to granules or vesicles . This pump
inhibited by Reserpine.
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7. Metabolism
• It metabolized by Mono-amino oxidase (MAO) at site of
axonal part and in periphery like liver ,blood and tissues,
it also metabolized by COMT (catechol-o- methyl
transferase)
Adrenaline -MAO - -3,4 dihydroxy NE
mandelilic acid
Vanillylmandelic acid(VMA)
Glucoronide or sulphate conjugation
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8. Receptors
• Adrenergic receptors act through G- Protein
coupled receptor which function primarily by
increase decreasing the intracellular function.
• Alpha (1 , 2 )
• Beta (1, 2 , 3)
• Alpha1 – main location
• Blood vessels- contraction
• Eye –mydriatics
• Prostate / urethera- decrease
• Alpha2- Pre-synaptic as well as post syneptic nerve
ending.
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Main location
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9. • Beta-1: locate on – Heart
• - Justa-glomular cells
• Beta-2 : on Bronchus
• GIT ,Bladder , uterus, BV ,
• Skeleton muscles , liver.
• Beta-3 : Adipose tissues.
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10. ClassifiCation of sympathetiC
drugs
• By mode of action
Direct acting- CA and Non CA
-Indirect acting- Tyramine, amphetamine, cocaine,
ephedrine,TCA
• By chemistry
–Catecholamines (CA)
–Non-catecholamines
• By selectivity (to types of receptor)
Direct acting
• classified by alpha, beta receptor subtypes
• α 1-selective, α 2-selective, nonselective
• β 1-selective, β 2 -selective , nonselectiv
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11. • Indirect acting sympathomimetic drugs
• tyramine
• amphetamine
• Mixed action sympathomimetics-
• Ephedrine
• Dopamine
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Classification
based on therapeutic
action
see in BOOK –page no. 88
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12. PRESSOR
AGENTS
CARDIAC
STIMULANT
BRONCHODILATOR
S
NASAL
DECONGESTANT
•Noradrenaline
•Phenylephrine
•Ephedrine
•Dopamine
•Methoxamine
•Mephentermine
•Adrenaline
•Dobutamine
•Isoprenaline
•Isoprenaline
•Salbutamol
(Albuterol)
•Terbutaline
•Salmeterol
•Formoterol
•Bambuterol
•Phenylephrine
•Naphazoline
•Xylometazoline
•Oxymetazoline
•Pseudoephedrine
•Phenyl
propanolamine
CNS
STIMULANT
ANORECTICS UTERINE
RELAXANT
•Amphetamine
•Methamphetami
ne
•Dexamphetamin
e
•Fenfluramine
•Dexfenflurami
ne
•Sibutramine
(Banned)
•Ritodrine
•Isoxsuprine
•Salbutamol
•Terbutaline
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13. PHARMACOLOGICAL ACTION
• In periphery adrenaline acts on alpha and beta
receptors of different tissues and organs . Some
important actions are –
• On Heart ;- Adrenaline increase the heart rate , by
acting on Beta-1 receptor and its result
Systole is shortened then diastole
Cardiac output and oxygen
consumption markedly increased.
Increase in atomicity , excitability which cause
cardiac arrhythmia .
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+ve chronotropic
+ve ionotropic
+dromotropic
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14. • Blood vessels – Vasoconstrictor(alpha-1) as well as
vasodilator (bata-2), depends on the action of
drugs. Action is most marked on arterioles due to
alpha-1, and larger arteries and veins due to beta-
2.
• BP- Noradrenaline causes vasoconstriction (alpha-1),
beta-1 receptor is responsible for increased in BP.
Result- increased BP, but it cause bradycardia- but adr
caused- tachycardia
• Respiratory systems – Adr and isoprenaline and NA acts
on beta-2 of bronchus results dilation of bronchial smooth
muscles . NA Potent bronchodilator (indirectly)but short
duration of action. Reduce secretions release mucosal
congestion by vasoconstriction.
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15. • Eye- mydriatics occurs due to radial muscles of
iris (alpha-1) .
• GIT – Gut relaxation occurs through activation of
both Alpha and Beta – receptors. Peristalsis and
sphincter are reduced but is not such effective ,so
no any clinical importance .
• Bladder – Detrusor is relaxed (beta-2) and trigone is
constrict (alpha-1) – resulting hinder micturition.
• Uterus – contraction through alpha while
relaxation through beta receptors .
• Skeleton muscles – Contraction of muscles, tension
developed in muscles fibers which may cause tremor
mediated by Beta –receptors.
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16. • CNS – clinical dose of adrenaline produced NO any
marked effects on CNS, because of poor penetration of
BBB. When injected in brain it produced excitation
followed by depression .
Activation of alpha -2 receptors of brainstem results in decrease in
sympathetic outflow and cause bradycardia.
• Metabolic – Increase blood glucose level by increasing
the cAMP in liver cell and stimulating glycogenolysis
through Beta -2 receptors . Gluconeogenesis and
Glycogenolysis may cause increase glucose level in
blood.
• Glands – decrease the secretion of glands.
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17. Pharmacokinetics
Adrenaline / CA are not suitable for oral route
due to different enzymes metabolism present in
GIT and liver like COMT and MAO.
Absorption is more rapid after intramuscular
injection but sometimes given as IV.
In anaphylactic it given as IV, due to poor
absorption.
catecholamine does not cross BBB.
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18. ADVERSE EFFECTS
Restlessness
Palpitation
Tremor
Anxiety
Tachycardia
Marked rise in BP
Cerebral hemorrhage
Cardiac arrest , cardiac arrhythmias.
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19. Contradicted
• In hypertension condition
• Hyperthyroid
• Angina pectoris
• With anesthesia like halothene
• Adrenaline contradicted in GTN , angina ,
CCF , arrhythmias
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20. • Nocturnal enuresis in
children and urinary
incontinence
• Uterine relaxant
• Insulin
hypoglycaemia
• Hyperkinetic children
• Narcolepsy
• Obesity
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VASCULAR USES
• Hypotensive state
• Along with local anaesthetics
• Control of local bleeding
• Nasal decongestant
CARDIAC USES
• Cardiac arrest
• Partial or complete A-V block
• Congestive heart failure (CHF)
• Bronchial asthma
• Allergic disorders
• Mydriatic
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21. • In cardiac arrest and heart block ,the drug of choice is
adrenaline (0.3-0.5 ml of 1;1000 solution) .
• Used in anaphylactic shock
• In acute bronchial asthma (beta-2 agonist)
• Inhibition of premature labour (salbutamol).
• In bronchial asthma ,
• Allergic
• for mydriatic ,
• Narcolepsy
• Obesity ,
• uterine relaxant , in hypoglycemia .
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22. • You have study important individual drugs of
sympathomimetic like-
• Ephedrine
• dopamine,
• Cocaine
• Amphetamine also
 Here two drugs are describe briefly for short answer
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23. Dopamine
• It is central neurotransmitter and it acts on dopaminergic and
adrenergic receptors .
• It is catecholamine, present in CNS as well as periphery,
transported in vesicles and blocked by reserpine .
• MOA- it acts on centrally present dopaminergic receptors D1,
D2 as well as beta-1, alpha-1 receptors (with increasing dose).
•
• PHARMACOKINETICS-
• Having high 1st
pass effect.DA is a substrate for both MAO and
COMT and thus is ineffective when administered orally, which
present in GIT and blood. Most sensitive to IV at low dose.
•
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24. • Pharmacological effects
• Heart –dopamine has direct action on beta -1 receptor
and act like positive chronotropic and inotropic and
increase HR
• Blood vessels – act as vasoconstrictor (alpha-1) –increase BP on
high dose .
• Renal – INCREASING g.f.r. and Na excretion. Activation of
D1 receptors in several vascular beds, of kidney which
leads to vasodilation. Diminished Na+ reabsorption by
the proximal tubular cells cause natriuretic (beta-1)
• CNS-There is no effect on CNS , due to DA not cross BBB .
• Therapeutic use – In treatment of septic shock specially with oliguria
patient's (dose is >2-10 mcg/body wt.) .In renal dysfunction and cardiac arrest
, CHF
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25. Amphetamine
• Non-catacholamine synthetic and sympathomimetic
drugs . It having both central and peripheral effect.
• MOA- It having indirectly stimulate adrenergic receptor
by increasing release of catecholamine including 5-HT .
P’COLOGICAL ACTION-
• CNS – Crosses BBB and act potent CNS stimulant ,
physical activity, alertness ,euphoria , reduces sleep
,reduces hunger and appetite. It also increase initiative
and self-confidence and increase capacity to work.
• Respiration – stimulate respiratory Centre
• Heart – low dose not effect but high dose cause positive
chronotropic.24-04-18 18:28 25

26. • p’kinetic – orally effective for long duration .
Crosses BBB. metabolized by liver enzymes.
Excreted through acidic urine easily.
• Therapeutic Use – In CNS stimulant
• In ADHD (attention disorder hyperkinetic
deficiency) in children.- drug-Methylphenidate
• In obesity.
• Increase Attention spasm
• Reduce sleep (Drug of choice- medafinil)
• Epileptics and parkinsonism .
• Week anticonvulsants, analgesic antiemetic, and acta
as synergetic to above drugs.24-04-18 18:28 26

27. It is one of the drug which used in Dope Test
• ADR-
• Amphetamine come under shedule-2
• These are drug of abuse and are producing
psychological dependency . (DOPING)
• Higher dose causes confusion delirium, acute
psychosis , coma and death also.
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Thank u
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