robin082006
Forum Hero
Topics: 471
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Yes and No are correct answer for a question like this
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| Flying h4x0r
Forum Junior
Topics: 4
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adrenaline = epinepherine
noradrenaline = norepinepherine
norepi stimulates alpha1, 2, and beta 1 recepotrs
epinepherine stimulastes alpha1, alpha2, beta1, and beta2 receptors
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| drpkaur
Forum Guru
Topics: 195
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As stated by Flying h 4x0r abt the receptors it's correct and further addition to this point is that Epi will have more effects on heart (beta1)-like it increases HR,conduction velocity,contractility ,cardiac output and 02 consumption ...due to alpha1 rec stimulation -causes vasoconstriction of arterioles of skin,viscera -leads to increase in mean BP ,Systolic rises but slight incr in diastolic or no change ,increased afterload but as epinephrine has affinity for beta 2 receptors so due to b2 receptor stimulation there will be vasodilatation of smooth muscles of blood vessels-leads to decreased diastolic pressure,peripheral vascular resistance therefore decreases.....moreover epinephrine has also effects on carbohydrate and fat metabolism-increases liver and muscle glycogenolysis-increases hepatic output of glucose ,increases plasma glucose.with fats-it increases the activity of hormone sensitive lipase -incr lipolysis-incr FFA in plasma...Epi also increases metabolic rate...so Epinephrine actions over heart as follows once again:incr HR,contractility,conductivity ,CO,incr Systolic bp ,diastolic bp slight incr/no change /may decrease,,so mean BP will rise...and above all TPR decreases....
For Norepinephrine---its major actions on peripheral circulation means mainly on alpha 1 receptors-increases systolic bp largely ,incr diastolic bp largely and mean bp increases...but here effect on heart rate will be slight incr /decrease /or no change..........
and above all there will be increase in TPR...
At low epinephrine doses,beta receptor stimulation predominates and at moderate to high doses,alpha receptor stimulation predominates...
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