Calcium‐sensing receptor expression and signalling in human parathyroid adenomas and primary hyperplasia

Abstract

The study shows that the activation of the calcium sensing receptors expressed in adenomatous parathyroid glands modulates intracellular effectors in a similar way to those operating in the normal parathyroid. Although a reduction of calcium sensing receptor expression is probably involved in the poor inhibition of PTH release induced by [Ca2+]o, this is not the only factor altering [Ca2+]o sensing in parathyroid adenomas, since tumours characterized by different in vitro sensitivity to [Ca2+]o showed similar CaSR levels. The low content of G proteins of the Gq subfamily might represent an additional alteration leading to a defective [Ca2+]o sensing.