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

1883 abolish the card ioprotecti ve effects channel openers but do not affect the
activity of other classes of anti-anginal agents [265].
There is a growing body of evidence to support the thesis that the activation of the
mitochondrial K,, N-ri, channels may be the protein effector responsible for the protection
observed in ischaemic preconditioning [99,196].
1.8 Human Models of Preconditioning
Despite the evidence suggesting the involvement of a number of potential theories for
ischaemic preconditioning protection there remains a lack of a unifying hypothesis or
pathway that may lead to protection. This makes it more Interesting which mediator (s)
may turn out to be involved in protection by ischaemic preconditioning in man. in
contrast to the animals used for experiments with their normal myocardium and coronary
blood flow, human subjects often suffer from anatomical coronary artery disease with its
associated haernodynarnic
consequences.
Although a limited number of human studies have been performed, it remains difficult
to adapt these models to investigate the underlying mechanisms of protection by
ischaernic preconditioning. Therefore in vitro human muscle preparations have been
developed which may be more easily adaptable for the purpose of investigating the
involvement of individual mechanisms.
1.8.1 In Vitro Models
A. Human Atrial Trabeculae
An in vitro human model of preconditioning has been developed in Yellon's
laboratory using isolated human right atrial trabeculae. This model allows ischaemic
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