BIOL 3051 Chapter Notes - Chapter 6.2: Cyclic Adenosine Monophosphate, Angina Pectoris, Ivabradine

• School: York University
• Department: Biology
• Course: BIOL 3051
• Professor: Hernan Humana

Document Summary

Cyclic amp sensitivity of hcn channels: camp shifts activation curve of hcn channels (depolarizing vm) increase camp ih more active at resting depolarized vm increase rate of spontaneous depolarization of ap firing. Hr: betablockers reduce camp less activation of ih no depolarization. Decrease hr: mach activation inhibits ac to decrease camp. Ach release via parasympathetic reduce ih decrease hr: sympathetic: release of ne/e increase camp increase ih faster hr, parasympathetic: release ach decrease camp decrease ih decrease hr. Ivabradine blocks pore from intracellular side (open channel, use dependent block: angina pectoris caused by cardiac ischemia, b/c ivabradine blocks hcn, slower depolarization, sloed hr. Ivabradine used to reduce hr when beta blockers contraindicated. Inhibits influx of na+ & efflux of k+ Integrating ion channel concepts with stubbed toe: harmful/noxious physical stimuli activate c/aa nociceptors, non-harmful/innocuous physical stimuli actives ab sensory neurons (mechanoreceptors, ab activates gabaergic interneurons (i) in spinal dorsal horn.