Special remarks: Salivary Chromogranin-A (CgA) shows a distinct circadian rhythm with a morning peak upon awakening. In contrast to this the plasmatic CgA concentration does not show such a pattern. This indicates that salivary and plasmatic CgA have different routes of secretion. Salivary CgA seems to be a useful marker for mental stress.
There is some evidence that salivary CgA can be used as a psychological stress indicator and is an indicator reflecting sympathetic nerve activities, different from cortisol. Because salivary CgA is faster acting and is more reactive than cortisol, studies have been conducted on CgA as an indicator for psychological stress.

General information: Chromogranin-A or parathyroid secretory protein 1 is a member of the chromogranin/secretogranin (granins) family of neuroendocrine secretory proteins, i.e. it is located in secretory vesicles of neurons and endocrine cells. Examples of cells producing chromogranin-A are chromaffin cells of the adrenal medulla, enterochromaffin-like cells and beta cells of the pancreas.
Chromogranin-A is the precursor to several functional peptides including vasostatin, pancreastatin, catestatin and parastatin. These peptides negatively modulate the neuroendocrine function of the releasing cell (autocrine) or nearby cells (paracrine). Other peptides derived from chromogranin-A with uncertain function include chromostatin, WE-14 and GE-25.
Chromogranin-A might promote the generation of secretory granules. It is used as an indicator for pancreas and prostate cancer. It might play a role in early neoplasic progression. It is also elevated in diabetes. Chromogranin-A is cleaved by an endogenous prohormone convertase to produce several peptide fragments.
The aminoacid sequence of CgA is: E-E-E-E-D-N-R-D-S-S-M-K-L-S-F-R-A-R-A-Y-G-F-R-G-P-G-P-Q-L-R-R