Pharma 11: Nicotinic Signalling - Junctions, Gates, and Thresholds

This episode examines nicotinic receptor pharmacology at two critical crossroads: autonomic ganglia and the neuromuscular junction. Here, signalling is rapid, decisive, and threshold-dependent—very different from the modulatory tone of muscarinic systems. We explore how drugs that act at nicotinic receptors can stimulate, block, or exhaust transmission, and why small shifts at these junctions can produce dramatic clinical effects, from paralysis to autonomic instability.Key takeaways you’ll build and reuse throughout the series:* Nicotinic receptors as fast gates: ligand-gated ion channels designed for speed and reliability.* Ganglia versus neuromuscular junction: shared receptors, different rules, different consequences.* Depolarisation block and desensitisation: why “more stimulation” can paradoxically silence transmission.* Therapeutic leverage points: anaesthesia, critical care, and procedural paralysis grounded in mechanism.* Adverse effects as physiology pushed past threshold, not unexpected toxicity. This is a public episode. If you'd like to discuss this with other subscribers or get access to bonus episodes, visit drmanaankarray.substack.com/subscribe