study_ing
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what concept are u particularly confused abt or is it a problem learning facts
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| waqastariq
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yups what do you want to know? 
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| DrVirgo
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This concept will help with a lot of the ANS tracings:
alpha 1--> VC--> Inc. TPR--> inc BP--> Reflex Bradycardia
beta 2--> VD--> Dec. TPR--> dec BP-->Reflex Tachycardia
beta 1--> Inc HR, Inc Pulse Pressure
Musc 2--> Dec. HR
Musc 3 -->VD --> Dec TPR--> Dec. MAP--> Reflex Tachycardia
Blood vessels have Alpha 1 and M3 Receptors but are ONLY innervated by SANS, NOT by PANS, so the drugs that can affect it are sympathetic agonists/blockers, and DIRECT acting drugs on Muscarinic receptors like Ach, but NOT Indirect acting drugs such as AchE-Inhibitors because those type of drugs work at the synapse, and there is NO PANS innervation of blood vessels.
Drugs with Alpha 1: Phenylephrine, Methoxamine, Epi, Norepi
Drugs with Beta 2: Metaproterenol, Albuterol, Terbutaline, Isoproterenol
Drugs with Beta 1: Isoproterenol, Epi, Norepi, Dobutamine
Drugs with Musc 2: Ach, Bethanechol, Carbachol, Pilocarpine, and AchE-Inhibitors
Ganglionic blockers will prevent the Reflex brady or tachycardia. (see above)
For drugs with dual action where there is change in Heart rate due to a reflex AND direct effects on the heart, giving a ganglionic blocker will BLOCK the reflex, buy you will still be able to see the DIRECT effects on the heart.
eg. Giving Norepi with a Ganglionic Blocker:
Norepi: alpha 1--VC--Inc. TPR --Inc MAP---Reflex Bradycardia BLOCKED!
BUT: beta 1---Inc. HR STILL PRESENT.
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| Cedrick
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What was the question ?
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| DrVirgo
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The question was "Autonomic Nervous System" !
I didn't want to write a chapter here so I just posted what I posted before in the pharm. notes section about doing the ans tracing questions.
Good luck everyone...
Pallav, If you have a specific question, it would be better to ask it that way.
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| Cedrick
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| pallav
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cedrick silly
you could have helped me in this hour of need?
you pain only you can feel
somebody rightly said
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| Cedrick
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Sorry
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