Trimodal pattern of CALC-I gene expression occurring in neuroendocrine cells, parenchymal cells and monocytes
| Thyroid | Parenchymal tissue | Monocytes | |
| mRNA | Constitutive | Regulated | Regulated |
| Protracted, sustained by cytokines and LPS | Rapid, transient upon adhesion | ||
| Detectable after >6 h | Detectable after >2 h | ||
| Protein | Regulated | Constitutive | Constitutive |
| Detectable after >10 h | Detectable after >4 h | ||
| Persistent (>24 h) | Transient (<18 h) | ||
| Tissue mass | Low | High | Low |
| Main function | Mature CT, e.g.↓ P-Ca2+ | Sepsis-associated PCT increase | Local vasodilation (CGRP, PCT?) |
LPS: lipopolysaccharide; CT: calcitonin; ↓P-Ca2+: lowering of circulating plasma ionised calcium levels; PCT: procalcitonin; CGRP: CT gene-related peptide. Adapted from 3.