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Old 11-15-2011
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Drug Dose Response Curve Question

Atropine is injected into a cholinergic nerve terminal within a salivary gland and the dose response curve is measured. Curve AB represents the nerve in the absence of atropine and curve CD represents the nerve terminal in the presence of atropine. The Y axis represents increasing gland secretions. The X-axis represents increasing ACh dosage. Which of the following is an accurate statement?

  • A. Atropine does not bind on ACh receptor
  • B. Atropine decreases the efficacy point of the dose response curve
  • C. Potency of ACh is decreased with Atropine present
  • D. Atropine binds and activates the ACh receptor
  • E. Atropine is a noncompetitive antagonist
Dose Response Curve Question-dose-response-curve.jpg
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CHAKRAM (11-16-2011), Dr. Mexito (01-09-2012), drpharma34 (11-16-2012), maddikrueger (02-25-2015), zohra (11-16-2011)



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Old 11-15-2011
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it is CCCCCC
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Old 11-16-2011
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yup the answer is c
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Old 11-16-2011
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Default potency of ach decreased in presence of atropine

the curve farther from the Y axis will have decreased potency
efficacy is defined by the height of the curve, which is similar
atropine is a competitive antagonist
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Old 04-25-2015
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Hi I am not a chemist but I need to calculate what a 16 ngml-1 dose of ACh is in units of mol L-1 (n.b. the molecular weight of ACh is 182). I do not have a clue where to start. Any help would be very gratefully received.

Last edited by penpet9; 04-25-2015 at 06:59 AM.
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