Together with Chromogranin B and Secretogranins, Chromogranin A (CGA) is stored 
in secretory (chromaffin) granules of the diffuse neuroendocrine system and 
released with noradrenalin and adrenalin. Co-stored within the granule together 
with neuropeptideY, cardiac natriuretic peptide hormones, several prohormones 
and their proteolytic enzymes, CGA is a multifunctional protein and a major 
marker of the sympatho-adrenal neuroendocrine activity. Due to its partial 
processing to several biologically active peptides, CGA appears an important 
pro-hormone implicated in relevant modulatory actions on endocrine, 
cardiovascular, metabolic, and immune systems through both direct and indirect 
sympatho-adrenergic interactions. As a part of this scenario, we here illustrate 
the emerging role exerted by the full-length CGA and its three derived 
fragments, i.e., Vasostatin 1, catestatin and serpinin, in the control of 
circulatory homeostasis with particular emphasis on their cardio-vascular 
actions under both physiological and physio-pathological conditions. The 
Vasostatin 1- and catestatin-induced cardiodepressive influences are achieved 
through anti-beta-adrenergic-NO-cGMP signaling, while serpinin acts like 
beta1-adrenergic agonist through AD-cAMP-independent NO signaling. On the whole, 
these actions contribute to widen our knowledge regarding the 
sympatho-chromaffin control of the cardiovascular system and its highly 
integrated "whip-brake" networks.