Calcitonin receptor-immunoreactive (CTR-ir)
endothelial and foam cells were identiWed in atherosclerotic
plaque within the abdominal and thoracic aortas of rabbits
fed a cholesterol-supplemented diet. Initially, cells within
the endothelial layers of nascent atherosclerotic plaque of
arteries were also CD34-positive, a marker of precursor
cells of the haematopoietic lineage. In a further rabbit
model with more advanced cardiovascular disease, CTR-ir
cells were located deeper within the plaque as well as
within the endothelial layer overlying the neo-intima.
Finally, in the third model, in which the 4-week period on
the atherogenic diet was followed by a 12-week period of
regression on a normal chow diet, during which serum cholesterol
levels returned to the normal range, CTR-ir was
markedly reduced in the stabilized Wbrous cap of plaque.
Thus, the expression of CTR is associated with the early
cellular events involved in plaque formation and is downregulated
as stabilisation of plaque progresses in the process
of healing.