Autnomic nervous system ( adrogernic blockers ) Flashcards
explain the Androgenic receptor
1- a1 : follows the Gq second massager
- location :
1-1 Blood vessel’s : V.c
1-2 Uterus : contraction ( but not strong for apportion )
1-3 Eye in the dilator pupil ( radial M.c) : contraction so cause Mydriasis
1-4 GIT & uriniry: in the wall > relaxtion of the wall and contraction of the sphincter
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2- a2 : follows the Gq second massager
-Location : they are presynaptic receptor so they located only in the nerves terminal , if they activated they inhibit the Norepinephrine and they called ( selective a2 agonist )
——-
3-B1 : follows the CAMP second massager
-location :
3-1heart > increase all the cardiac properties:
HR,contractility,conductivity,Etc
3-2:Kidney > they are responsible for secretion of Renin
3-3 : Adipocytes
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4-B2 : follows the Camp second massager , and its the main roller of fight or flight mode
-location :
4-1:Skeletal muscles :
- facilitate of the nerve muscular transmission
-increase the blood flow by v.d of the blood vessels
-potassium shift : from the blood to the muscles but could cause hypokalmia
4-2:Coronary artery > dilation
4-3: Bronchi > bronchial dilatation
4-4:Liver : gulcogen to glucose
4-5: Eye: regulating the Eye pressure by increase the secretion of Eqousumer
4-6: Uterus > relaxation of the muscles in the Emergency time to prevent apportion
NB! sometime cause Tremors
——
5-B3:follows the Camp second massager
-location : in the adipocytes tissue specifically in the upper part of the body so when its activate cause Lipolysis
explain the Indirect sympathomimetics
-Drug : Amphetamine
- its non -caticolmine so it pass BBB and orally absorbed
- mechanism: mediate the primary action by blocking neuronal uptake of The Dopamine , Norepinephrine,serotonin and promoting the release from store sites of CNS which lead to accumulation of these mediators in the synaptic gap which will stamulate the Entire CNS and stimulate a + B receptors
— Pharmacological effect:
1- CNS stimulation 2- Anorexia
3- Euphoria 4- hallousantion
5 adductive
— uses or treatment : its banned duo to its multiple effect in the CNS but it was used for
1- CNS stamulance 2-obesity
explain the The Orthostatic hypotension or Postural hypotension
- in the normal person : when the body in laying position and try to wake up to standing position the blood will move to the lower extremity so in the normal patient the body will do a V.c in the lower extremity to balance the Bp
-in person with Postural hypotension:
when the body change to standing position the body doesn’t reacts by V.C which cause hypotension by lowering the Bp in the systole 20 mmhg
— reason for this disease:
1- Diabetes mallets
2- Autonomic neuropathy
3- antidepressants drugs
4- a blockers
explain the RT and RB
-Reflex Tachy : its caused by a sudden fall of the Bp so the stretch receptor which located in the Aorta will send a signal to the sympathetic system which lead to reflex tachycardia and rise the blood pressure
- reflex Brady: its happens when a sudden rise of the Bp so the stretch receptor send a signal in the Cardio inhibitory center which is mediated vegally and do bradycardia
—- acceptation : if the drug that did the sudden change in the Bp in the same time has direct effect on the heart the reflex will not appear - Ex Adrenaline and B blockers
explain the the (a) adrenergic blockers
- they are 3 classes :
1- a1 + a2 non selective blockers
2- a1 selective blocker
3- a2 selective blocker
explain the (a non selective blockers )
—Drug : Phenoxybenzamine , Phentolamine
-mechanism: irreversible antagonist at both a1 & a2 its bind covintally with receptor which lead to long blocked of the receptor
- pharmacological effect:
1-orthostatic hypotension
2- reflex tachycardia
— uses : to treat Pheochromocytoma but it should be described with B blacker ( Propranolol )
- side effect :
1-orthostatic hypotension
2- impairment of ejection ( male )
3- Meiosis > bcs blocked of a1 in the eye ( redial M.)
what is the Pheochromocytoma ?
- its tumor in the supra medulla gland which responsible for secreting the adrenaline and this tumor will increase the secretion
explain the Selective a1 blocker
- Drug : 1- Prazosin 2- Doxazosin
3-Tamsulosin - mechanism: blockes a1 receptor mainly in the blood vessels which lead to V.c and relaxation of smooth muscles of artery and vines
- pharmacological effect :
it cause minimal changes in :
1- renal blood flow
2-Glomerular filtration rate
and improve lipids profile
— uses or treatment:
1- mild or moderate hypertension
2- treatment of congestive heart failure by decreasing the pre load and after load
3- prostatic hyperplasia ( enlarged prostate ) we use Tamsulosin
— adverse effect :
1- first dose hypotension
2- fluid retention
3- false positive test of antinuclear factor of rhemtoid arthritis
4- in female urine incontenance
explain the selective a2 blocker
-Drug : Yohimbine
- mechanism: selective a2 blocker presynaptic in the nerve ending
- phramalogical effect : leads to increase the norepinephrine release
- uses : Used sometimes as Aphrodisiac without clinical evidence
explain the classes ,Prototype , chemistry, pharmacokinetics, mechanism, pharmacological effect of ( B ) blockers
- classes :
1- B1+B2 blockers
2- B1 blockers
3- mixed B+a blocker
—- Prototype : Propranolol
——- chemistry:
they are 2 types :
1- lipophilic : B-blocker ex Propranolol can pass to CNS and cleared by haptic metabolism ( first pass metabolism)
2- hydrophilic: B- blocker ex Atenolol have limited penetration to CNS and execrated primarily by kidney with little of hepatic metabolism
— Phramcokintks :
1- absorption: B- blockers are absorbed well after oral administration and many of them have low Bioavailability because of extensive first pass metabolism
— mechanism: blocked B1 + B2 receptor
—Pharmacological effect:
1- C.V.S :
1.1 - Heart (b1) : decrease the cardiac properties
1.2 blood vessels (b2) : prevent the V.D from B receptor in the - coronary artery
-skeletal muscles blood vessels
1.3 Bp : hypotension by > decrease the Cop , Decrease secretion of renin , resting of the baro reflex
2- respiratory : by blocking the B2 in the bronchi the dominant will goes to the parasympathetic which lead to 2.1-B.C
2.2- bronchospasm
3- eye : decrease the IOP duo to blocking the B2 in the epithelium in the ciliary body
4- CNS : anxiety , nightmares , sexual dysfunction
5-skeletal M. : decrease the Essential Tremors
what is the special effect of the B blocker drugs
- Propranolol: has local anesthetic ( inhibit excitability of cardiac muscle)
-Pindolol : its partial antagonist ( so no excessive bradycardia )
-Esmolol : it has very short acting ( so it used during surgical operation for acute hypertension)
-Labetolol : blocks a and B receptor so its good for pheochromocytoma - Carvedilol : antioxidant action
- Nebivolol : its the most selective B1 blocker
Explain the treatment or uses of B blockers
1- hypertension
2- ischemic heart disease ( classic angina )
becs> decrease the myocardial work , increase the systole fling time
, Redistribution of the blood ,
metabolic switch from FFA to glucose
3- Supra ventricular tachy S.V.T :
its disease that is the SA nodes increase the condectellty so by blocking the B1 we decrease the condactellty and increase the refractory period of SA nodes
4-hyper trophic myobothy
5- hyperthyroidism
6- esophageal verses
7- glaucoma : timolol and betaxolol bcs they are lipophilic
8- pheochromocytoma
what is the adverse effect of B blocker
1- fatigue
2- broncho construction
3- Brady cardia or heart block
4- Prephral ischemic
explain the B blocker class ( mixed antagonist)
—Drug : 1- Carvedilol
- mechanism: inhibit b and a1 receptor
- uses: in emergency for acute hypertension
and for pheochromocytoma
- side effect : hypotension
explain the B blocker non-selective
- Drug : 1- Propranolol 2-Timolol
-mechanism: block the B1 and B2 receptor
-pharmacological effect :mentioned in the general description of the B blocker
-uses : 1- hypertension
2- ischemic hear disease ( classic angina )
3-Cardiac S.V.T
4-hyperthyroidism - side effect :
1- broncho construction
2-hypotension
3-bradycardia
4-heart failure
