ischaemic preconditioning of the human heart. - Leicester Research ...

examined the supernatant from cells, and found that the preconditioned cells had lower
hydrogen ion, lactate and lactic dehydrogenase
concentration.
Using this isolated cardiomyocyte model it has been shown that the exogenous
administration of adenosme can mimic ischaernic preconditioning protection. In addition,
administration of the supernatant from preconditioned cells was shown to protect other
cardiomyocytes that did not under go a preconditioning protocol, and that this protection
could be blocked by the administration of the adenosine receptor antagonist 8-p-
sulfophenyltheophylline (SPT) [ 139].
1.8.2 In Vivo Models
A. Angioplasty
Percutaneous transluminal coronary angioplasty (PTCA) provides an oppurtunity
to study the human heart with respect to controlled regional ischaemia and reperfusion. It
has been shown that following the first balloon inflation subsequent balloon inflations
causes less chest pain, less ST segment shifls and less lactate production [79]. However,
these studies must be interpreted with some caution because of the short periods of
ischaernia involved (less than 2 minutes) and the possible role in the recruitment of
collateral ciruclation. However, the same investigators [78] went on to report that the
adaptation to ischaernia was probably not due to an increase in coronary collateral blood
flow. Although Cribier et al [661 showed similar reduction in severity of angina and
degree of ST-segment elevation, but acute recruitment of coronary collateral flow
occurred and may have lead to the improvements observed
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