PHAR 562 Lecture Notes - Lecture 19: Trpv1, Nerve Block, Allodynia
12 Feb 2020
School
Department
Course
Professor
Document Summary
Affects 10-15% of the individuals of a society at any given time. Costs at least 100 bn$/year: total cost due to lost labour days, etc. Impact on society depends on specific type of pain lower back pain is the most common pain type. Has huge impact on patient due to comorbidities. V1 and v2 detect painful heat periphery for local anaesthesia: lidocaine. Sodium is crucial for neurotransmission and so v-gated na+ channel blockers are used, particularly in the. Injection of anaesthetics into drg can shut down sensation in whole dermatomes. Drugs can have very narrow therapeutic windows: v-gated na+ channel blockers can lead to cramps, seizures, decreased consciousness all the way to respiratory arrest, because they are expressed in all excitable tissues. Nociceptors can be sensitized to lower their activation threshold: for example: trpv1 that gets sensitized to open at 30 degrees instead of 45 degrees patient feels thermal pain at normal body temperature (allodynia), and the pain is spontaneous.
