PHRM 211 Lecture Notes - Lecture 12: Postherpetic Neuralgia, Orthostatic Hypotension, Tricyclic Antidepressant
Document Summary
Pharmacology review of pain medications (part 2) Drug of choice in patients with co-existing depression. Block cortical ach, alpha, ha receptors sedation. Block ach, ha receptors on nociceptive pathways analgesia. Block ion channels (na+ channels) in periphery nociceptor endings may reduce. Na reuptake blockade is more important than 5-ht reuptake blockade for mediating analgesia. Structural analogs of gaba (no effects on gaba receptors) Bind to the 2 subunit of voltage-dependent ca2+ channels. Moa : reduces ca2+ influx into presynaptic afferent terminals located in the superficial laminae of the spinal dorsal horn. Useful particularly in stabbing or shooting pain. Control response shows high frequency response to intracellular stimulation (injection of square wave pulse, 2 namps in magnitude) Cell is still capable of firing to synaptic inputs, but at low firing rates only. Moa : blocks voltage-dependent na+ channels and high-frequency burst discharge. Moa : inhibits release of excitatory neurotransmitters from presynaptic neurons.
