what are calcium channel blockers?

[ttweed@wildrockies.org (Tony Tweedale)]

  >what are calcium channel blockers?  Are ordinary calcium supplements in this
  >category?
  >viv mountford
  >>
  >>At 11:43 17/10/97 -0400, Tony Tweedale wrote:
  >>          "Calcium Channel Blockers May Raise [breast] Cancer Risk
  >>[Findings]."          Washington Post, 16 October 97, A8.
  
  --
  i wanted to take a stab at this despite being eminetly UNqualified, becasue
  i just happened  yesterday to be reading the intro articles from an '89
  niehs symposia on [Ca2+]i  (intracellular calcium ion concentrations)
  toxicicology.  aside from the item above, my recent post on 'evolution of
  Ah receptor' mentions calcium upset caused by oxidative damage.
  
  i never realized calcium biology was so ubiquitous!  for one, it serves as
  a hormone w/ regular protein receptors to transduce a multitude of messages
  and to maintain Ca homeostasis  (in fact, these are the 2 broad functions
  of calcium, but it's major applications in the body seem to number in the
  dozens).  so the breast cancer connection may have to do w/ the multitude
  of steps in Ca/receptor activties.
  
  to get to your Q., a major role of Ca is in cell membrane passage (in &
  out).  heavy metal competitors to Ca for binding to proteins involved in Ca
  channel activities are one category of blockers, i believe i read.  all i
  know about dietary Ca supplements is that one form is effective for bone
  density, another not.
  
  
  
  tony tweedale