Posted by KaraS on December 4, 2004, at 16:00:13
In reply to Re: Whats your take on Zinc Larry, Anyone ??, posted by Mistermindmasta on December 4, 2004, at 14:02:53
It's very long so here are a couple of paragraphs first. Then I'll give you the link if you want to read more.
"Extracellular zinc may gain access to intracellular compartments through NMDA receptors [100], calcium-permeable AMPA receptors [101], or voltage-gated calcium channels [102]. After entering the cell, zinc can trigger widespread disruptions of normal cellular functions. Zinc has been proposed to disrupt calcium homeostasis [102], inhibit mitochondrial electron transport [52], disrupt tubulin assembly [103], and overactivate calcium-mediated enzymes [104]. Furthermore, zinc reacts with the thiol and imidazole moieties of many proteins, and, thus, can disrupt their structure and function [105]."
"Toxic effects of zinc on hippocampal and cortical neurons also have been observed in models of Alzheimer's disease. Recent in vitro studies have shown that zinc induces beta-amyloid (betaA) protein clumping similar to that found in the senile plaques associated with Alzheimer's disease [73-77]. This aggregated (clumped) form of betaA protein has been found to be cytotoxic to hippocampal and cortical neurons, and it has induced apoptic cell death in in vitro studies [78]. betaA protein also has been shown to enhance the susceptibility of cultured human and murine cortical neurons to excitotoxic injury [79, 80]. Bush and colleagues have reported that low (i.e., physiological) concentrations of zinc (e.g., <5 µM) can aggregate betaA [73, 74]."
http://www.protein.bio.msu.ru/biokhimiya/contents/v65/full/65070949.htm
poster:KaraS
thread:423511
URL: http://www.dr-bob.org/babble/alter/20041123/msgs/424397.html