Figure 5.Calcium-sensing receptor (CaSR) expression in normal parathyroid glands, 1° hyperparathyroidism (adenomas), and 2° hyperparathyroidism (glands exhibiting diffuse or nodular hyperplasia, from dialysis patients). Decreased expression of both CaSR protein and mRNA in the majority of hyperplastic glands, with a particularly marked decrease in nodular type 2° uremic hyperparathyroidism.