Plant Selection & Phytochemistry

Kyoko’s selection of plants is very much intentional, and I think especially that the plants she picked out for their poisonous properties are worth discussing briefly. If you look into the mechanisms and the pharmacology of them, you’ll find that they vary widely. In fact, she has very little overlap in mechanism, and she has one example of each of the major modes of action employed by dangerously toxic plants.

Aconitum elevates sodium channel activation, making neurons unable to repolarize after an action potential; this leads to paralysis and death by respiratory failure. Digitalis is a cardiac glycoside, meaning that it impairs sodium/potassium pumps in the heart; this leads to slower heart rate, higher blood pressure, arrhythmia, and eventually heart failure. Belladonna is an antimuscarinic agent, meaning that it inhibits muscarinic acetylcholine receptors. This causes delirium, hallucinations, and heart failure. Hemlock contains antinicotinic compounds instead, and impairs nicotinic acetylcholine receptors, leading to sedation, paralysis, and eventually respiratory failure. Water hemlock is a stimulant that leads to confusion, seizures, arrhythmia, and a wide variety of problems associated with ongoing convulsions; death is usually by respiratory or cardiac failure, though hyperthermia and kidney failure as a product of prolonged seizures are possible. Autumn crocus impairs a protein called tubulin, leading to vomiting, anemia, internal bleeding, ascending paralysis, and hypovolemic shock. Internal bleeding can be lethal, and if not, multiple organ system failure is possible. Yellow jessamine is a sedative and muscle relaxant, which acts as a glycine agonist; higher doses can lead to vomiting, blindness, and respiratory failure. Bloodroot impairs Na/K pumps like digitalis, but this time at a local level, causing localized necrosis. Pennyroyal is metabolized in the body to produce a number of compounds toxic to the liver, leading to multiple organ failure. Japanese skimmia is phototoxic, meaning that it causes the body to develop a severe rash when exposed to sunlight; it is also impairs acetylcholinesterase, which at high doses produces the same effects as nerve agents/nerve gas. Lobelia has a wide variety of neurotoxic effects, which can cascade into hallucinations, confusion, vomiting, respiratory and cardiac complications, and seizures.

Kyoko doesn’t just have a bunch of poisonous houseplants. She has a selection showcasing a very wide variety of toxins, things that do all these different things to the body. There is little to no overlap. You don’t end up with this perfect of a sampling by accident, and that she has this selection in particular suggests a number of things about her. It’s very subtle, and I am guessing most people wouldn’t know this, because it’s not as though the average person has extensive knowledge of the mechanisms by which poisonous plants kill people. But this kind of subtle detail about a character is something I try for. I thought I’d point this one out, because it’s a great example of how I go about writing a character and what the thought process is like.