Re: Lead plus acid.


I'm getting so little work done this week. How does lead "mimic calcium" in the nervous system? Also, oops:

Because lead pipes were more expensive and considered more desirable than iron pipes, we expect that wealthier and better-educated cities were more likely to use them than poorer and more poorly educated cities. City officials chose lead pipes because they are more malleable and more durable than iron pipes (Troesken and Beeson 2003, p. 190). Malleable pipes can be bent around obstacles, reducing labor and materials costs. Durable pipes require fewer repairs and need to be replaced less frequently than less durable pipes. [...] With no sources of comprehensive city-level data on wealth, income, or inequality in 1900, we calculate the home ownership rate as a proxy for average city wealth and the literacy rate as a proxy for average city education.

Posted by: lurid keyaki | Link to this comment | 05- 5-16 11:20 AM
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Sounds like the answer is "pretty much any way you please." I wondered if the difference in ion size was significant; no evidence below to suggest that it is. This is sketchy; is it accurate?

Lead exerts numerous adverse mechanisms of toxicity. Lead has a high affinity for sulfhydryl groups. It is therefore particularly toxic to multiple enzyme systems. Many of lead's toxic effects also result from its inhibition of cellular function requiring calcium. Lead binds to calcium-activated proteins with much higher (105 times) affinity than calcium.
The interaction of lead and calcium with cellular sites depends on the concentration of free ions present (ie, Pb2+ and Ca2+). Pb2+ and Ca2+ compete at the plasma membrane for transport systems, which affect their entry or exit (ie, Ca2+ channels and the Ca2+ pump.) Intracellular Ca2+ is buffered by proteins, endoplasmic reticulum, and mitochondria; Pb2+ disturbs this intracellular Ca2+ homeostasis. A (Ca2+)-(Pb2+) interaction at the mitochondria has been described.
Pb2+ interacts with a number of Ca2+ -dependent effector mechanisms, such as calmodulin (a Ca2+ receptor protein, which couples to several enzymes, eg, phosphodiesterase, protein kinases), protein kinase C, Ca2+ -dependent K+ channels in the plasma membrane and neurotransmitter release.

Posted by: lurid keyaki | Link to this comment | 05- 5-16 11:33 AM
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OMG, everyone's holding their breath waiting for a third ignorant lead trivia copy/paste from me. This is my moment, and... I don't know what to say... er.... These statistics, sobering as they are, are all dwarfed by the sheer number of murders committed with the lead pipe in the ballroom alone since 1949! Also there are no figures and tables in the linked paper, and actually maybe the size of the lead ions is the issue with "blockage of voltage-sensitive calcium channels." Finally, I love italics.

Posted by: lurid keyaki | Link to this comment | 05- 5-16 12:02 PM
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sheer number of murders committed with the lead pipe in the ballroom alone

It was Col. Mustard who done it.

Posted by: Barry Freed | Link to this comment | 05- 5-16 12:05 PM
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There's a lot of detail here, looks like it's the source of your second paragraph:

Calcium pump drives a lot of biochemistry, looks like Pb2+ interferes with normal dynamics.

Posted by: lw | Link to this comment | 05- 5-16 3:05 PM
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