Figure 3.

Absence of response to HH ligands in atherosclerotic plaques. (A) Atherosclerotic plaques were collected from 24 patients undergoing carotid endarterectomy for symptomatic high-grade stenosis of the internal carotid artery. Renal arteries from four family kidney transplantation donors were used as healthy control vessels. HH ligand expression and pathway activity was assessed by quantitative reverse transcriptase PCR. Expression of HH pathway targets GLI1 (B) and PTCH1 (C), as determined by quantitative reverse transcriptase PCR, was correlated with the expression level of HH ligands in atherosclerotic plaques. (D) The low levels or absence of HH target gene products were confirmed by Western blotting analysis in the same 24 subjects. (E) Radioimmunoassay analysis of three major plasma lipoproteins reveals that LDL contains the highest concentrations and VLDL the lowest levels of the endogenous HH signaling antagonist 25-OH vitamin D3 (25-OHvitD₃).