The basic concept of sympathomimetics
Okay we will check into the basic difference between epinephrine norepinephrine and isobrane first spin afraid okay next norepinephrine and isoprody okay first we have to check into the receptors it acting on first is alpha one yeah this uh epinephrine acts on alpha one receptor alpha two receptor and uh beta one and beta two next norepinephrine doesn’t act
On beta two and it acts on only alpha 1 alpha 2 and beta beta 1 and beta 3 beta 1 and 3 and the isoflavone acts mainly on beta 1 and beta 2 no alpha action beta 1 and beta 2 okay now the properties because as they are acting on alpha 1 2 beta 1 and 2 is as you all know alpha when alpha 1 is uh stimulated it will cause vasoconstriction so in this diastolic
Bp and systolic bp both sorry uh in case of epinephrine system bp increases first bp increases and diastolic bp decreases because of beta2 action and overall the mean arterial pressure will be uh a little above the normal mediatory pressure increase this story pp increase is due to alpha one action uh and this diastolic vp degrees is due to beta two action
And now about norepinephrine in case of norepinephrine it doesn’t have beta2 action so here systolic bp increases systolic bp increases and diastole bp also increase the installed vp increase so that uh the mean artillery pressure so the heat will be like a little bit above the normal now about isotropic in case of isoprenary it acts only on beta-1 and beta-2
Receptors plus beta-3 but no alpha action so there will fall in diastolic bp because of uh vasodilation due to beta2 receptor this foreign diastolic bp will be much more than the fault due to epinephrine so here also historic bp increases test all bp for more foreign much less and me mean me vp is also less so now we will check into the heart rate first about
Epinephrine in case of epinephrine heart rate will increase because diastolic group increase decreases due to vasodilation the do because of this vasodilation there will be reflux tachycardia so there will be tachycardia in case of norepinephrine there will be bradycardia like initially for a small period there will be time cardia then there will be guardian
Reflex bradycardia okay in iso finale there will be much more tachycardia that much more so now the bp this is about heart rate uh these are the main difference between these two so their use also varies because of this uh difference in their receptors first about epinephrine where we use epinephrine mostly eczema is the drug of choice for cardiac arrest partial
Rest because of its action on beta 1 because because of the beta 1 beta 1 which is present in the heart the heart contractility will increase so it is the truck of choice for cardiac arrest and also this is the drug of choice for anaphylactic shock and i feel like dick shock and the reason for this is uh it is due to his stamina release his tummy is causing the
Vasoconstriction in a phyllactic shock so uh here it has action on beta2 because of this beta2 action there will be lasso uh bronchodilation so it is a talk of choice for cardiac arrest anaphylactic shock and brittle asthma brittle asthma okay now about norepinephrine norepinephrine it doesn’t have beta to action so there is no vasocon it is the so it is mainly
Alpha one action which goes for asu construction so it is uh drug of choice for vasodilatory shock vaso dilatory shock iso dietary shock then uh and also cardiogenic shock or conditions where we need vasoconstrictions usually shock and also never is the drug of choice for neurogenic shock because uh for example neurogenic shock in case of an accident where
There is damage to thoracolumbar region and those of ganglion if the ganglia is closed there will be no release of the neurotransmitter norepinephrine so we have to give exogenously this noradrenaline that is normal eurogenic shock okay these are the main difference between epinephrine norepinephrine and isopronate hope this is useful
Transcribed from video
Epinephrine,Norepinephrine and Isoprenaline By neetpg mom’s concepts and facts