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Nifedipine is an antihypertension medication that is also used to reduce the workload on the heart. The study below compares the effects of two different types of capsules used to administer the drug to patients (GITS—red line, and Cotracten X—blue line). Each graph shows changes with time following initial administra- tion of the capsules. Figure A compares the levels of nifedipine in the blood with each capsule type. The ability of the different cap- sules to reduce workload on the heart by altering blood pressure or heart rate is shown in Figures B and C, respectively.
Are elevated plasma levels of nifedipine(above 10 ng/mL) required for the drug to perform its actions?
Source: M. J. Brown and C. B. Toal. 2008. Formulation of long-acting nifedipine tablets influences the heart rate and sympathetic nervous system response in hypertensive patients. British Journal of Clinical Pharmacology 65:646–652.
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Chapter 44 Solutions
Biology: The Dynamic Science (MindTap Course List)
- Nifedipine is an antihypertension medication that is also used to reduce the workload on the heart. The study below compares the effects of two different types of capsules used to administer the drug to patients (GITSred line, and Cotracten Xblue line). Each graph shows changes with time following initial administra- tion of the capsules. Figure A compares the levels of nifedipine in the blood with each capsule type. The ability of the different cap- sules to reduce workload on the heart by altering blood pressure or heart rate is shown in Figures B and C, respectively. Which type of capsule would you expect to have fewer side effects? Source: M. J. Brown and C. B. Toal. 2008. Formulation of long-acting nifedipine tablets influences the heart rate and sympathetic nervous system response in hypertensive patients. British Journal of Clinical Pharmacology 65:646652.arrow_forwardThe circulatory system is controlled in the Medulla oblongata through the accelerator and inhibitory centres. Draw a schematic diagram to show the sequences of events following low or high blood pressure detected at the baroreceptors.arrow_forwardFrom the experimental activity for PhysioEX Which of the following forms the (Y) axis of this graph Which of the following forms the (X) axis of this graph (A) Y - vessel length / X - flow rate (B) Y - flow rate / X - vessel length (C) Y - flow rate / X - peripheral resistance (D) Y - peripheral resistance / X - flow ratearrow_forward
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