Transcellular transport of intestinal calcium is accomplished by entry into the epithelial enterocytes via
A) a sodium-iodide transporter.
B) osteoclasts.
C) apical calcium channels (TRPV6 = ECaC).
D) CaSR (calcium sensing receptor).
E) an amino acid transporter (MCT8).

Question

Quizplus · Accepted Answer

Intestinal calcium is transported across the epithelium of the small intestine via calcium channels on the apical (luminal) side of enterocytes called TRPV6 or ECaC (epithelial calcium channels). These channels are highly selective for calcium and are responsible for the majority of calcium uptake in the small intestine. Sodium-iodide transporters are involved in the transport of iodide, not calcium. Osteoclasts are involved in bone resorption, not intestinal calcium uptake. The calcium sensing receptor (CaSR) is involved in regulating calcium homeostasis, but not in the transcellular transport of intestinal calcium. MCT8 is an amino acid transporter, but not involved in calcium transport.

Transcellular Transport of Intestinal Calcium Is Accomplished by Entry into the Epithelial