dimanche 21 juin 2009

Epinephrine and drug overdose, or the SVT bac


It managed not to rain, and I managed to kill my back working in the garden. I didn't realize how heavy the root ball of a laurel rose bush is. It's full of sort of ceramic stone things, to imitate the irascible conditions along a freeway in California and make it happy.

Among other things, like cleaning the pool, telling my husband exactly what is wrong with our marriage and life in exhausting detail for the thousandth time (never fascinating or helpful, but we've had too many late nights and I am probably a little over-sensitive), deadheading all the roses and other flowering plants on the top two terraces, mowing those two lawns, cutting out all the dead branches and black leaves of a Japanede acuba (I don't particularly like these plants, nor does my husband; one thing we do have in common) attacked by a mystery illness (probably a terrible fungus) and watering many things, I dug up the laurel rose I can't figure out what to do with and stuck it in a big terracotta pot.

It was originally where my Judas tree is, down behind the gazebo, where it wasn't getting enough sun, but was doing far better than where I put it, farther back behind the palm tree, under the neighbors' fig tree, which drops under-ripe figs onto our lawn, where they then rot and smell not so good. Every leaf turned brown and fell off there. At Fay, the laurel roses were all in large terracotts pots along the rear terrace, where they were doing very nicely. Mine was valiantly -- but excruciatingly slowly -- sprouting new leaves. At the rate it was going, it might be covered with leaves in 2 or 3 years and flowers in another 2 or 3. I want leaves this year and flowers by next year, at the very latest. I didn't, after all, buy this big, yellow-flowering laurel rose to do nothing in the garden. Everyone has to pull his weight here.

I put extra not so good dirt in the pot, since they thrive along highways in full Calfornia sun, cut off some more branches, shortened some others, gave it a little water and an ultimatum to do better than the camellia in the CRRA; nothing whatsoever appears to be happening there, although I repotted it again to see if I really can't get it to grow some useful roots to replace the ones the fungus and cold killed.

Sam spent his first day of summer studying for the bac. He has the 4-hour written French bac at 8 am, and he is determined to nail it.

Oh, Sam, do I hope that you will. He deserves it. He has been working so hard for this to make sure he does at least as well as last year (so as to make his year not a perfect loss), or better.

The last few days have been bac preparation classes at school, French and science. The two subjects they pass this year. He didn't do so well in Science last year, which he chalked up to apathy and a failure to apply himself. Terrible for a kid who actually is interested in the stuff of science class.

On the way to dinner with friends in Les Andelys last evening, he was chatty, which is understandable for a 17-year-old who hadn't spoken to a human being all day, but he even wanted to chat about the neurologic system.

"Did you know that if you give a person who has overdosed a shot of adrenaline, it saves them?" I haven't seen Pulp Fiction, so I didn't know until I checked his story out that the teacher must have.

His explanation, unrefuted somewhat unbelievably by his doctor stepfather, present at the dinner table, included mention of dopamine and the epinephrine blocking the brain's ability to be affected by the drug. Hm. I can't find anything, anywhere on Google that makes that claim, and dopamine, like epinephrine and norepinephrine, is a catecholamine, produced by the adrenal medulla, and are part of the sympathetic nervous system. Their release is part of the "flight or fight" response, and they do act to improve or restart cardiac function:
The sympathetic nervous system is responsible for up- and down-regulating many homeostatic mechanisms in living organisms. Fibers from the SNS innervate tissues in almost every organ system, providing at least some regulatory function to things as diverse as pupil diameter, gut motility, and urinary output. It is perhaps best known for mediating the neuronal and hormonal stress response commonly known as the fight-or-flight response. This response is also known as sympatho-adrenal response of the body, as the preganglionic sympathetic fibers that end in the adrenal medulla (but also all other sympathetic fibers) secrete acetylcholine, which activates the great secretion of adrenaline (epinephrine) and to a lesser extent noradrenaline (norepinephrine) from it. Therefore, this response that acts primarily on the cardiovascular system is mediated directly via impulses transmitted through the sympathetic nervous system and indirectly via catecholamines secreted from the adrenal medulla.
http://en.wikipedia.org/wiki/Sympathetic_nervous_system
But, epinephrine does not block dopamine or "stop the brain's ability to be affected by the drug taken". At least not that I can find.

My husband does use epinephrine in the event of neonatal cardiac failure, which he did say, but he didn't correct Sam's other statement concerning the blocking capacity of epinephrine.
Epinephrine is indicated during resuscitation of cardiac standstill or cardiac arrest. {01} {60} Epinephrine is used as an adjunct to restore cardiac rhythm in the treatment of cardiac arrest due to various causes. {01} It also has beneficial hemodynamic effects in the setting of cardiopulmonary resuscitation (CPR), improving myocardial and cerebral blood flow.
http://www.drugs.com/mmx/dopamine-hydrochloride.html

I'd go quiz my husband on his puzzling omission of a correction and possibly learn that Sam was right and why, except that I am still feeling too inclined to prove my earlier poolside points to enter into willing and civil discourse of the intellectual (or any) sort.

What interested me most was his adding last night in the car, when he first brought this up, that his SVT (science) bac preparation sessions have been small -- only 5 or 7 students --, and this has let them exchange and discuss with the teacher, ask their questions, and permitted him (he said) to adapt the class to his needs.

"Now I understand," he said, "why it's worth it to spend 10,000 euros a year for private school with small class size."

Was that a hint?

Ask the frog.
....

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