Vasostatin-1

Where it comes from

Made in

Chromaffin cells, sympathetic nerves and the heart, cut from chromogranin A

Sent out by

With catecholamines; chromogranin A rises in heart failure and sepsis

Acts on

• Arteries
• Heart muscle
• Endothelium
• Microbes

What it does

• Relaxes vessels already constricted by noradrenaline or endothelin, including human veins stripped of their endothelium ¹
• Weakens the heartbeat and counters adrenaline on the heart ²
• Antimicrobial in the laboratory, as several granin fragments are ²

In medicine

• No medicine and no test for the fragment. Chromogranin A itself is measured as a neuroendocrine tumour marker, and that number reflects the whole protein and all of its pieces together ²
• Chromogranin A rises in heart failure, sepsis and kidney failure, and on proton pump inhibitors; none of that says how much vasostatin-1 is present ²
• The assays are the obstacle. Vasostatin-1 is the front of chromogranin A, so an antibody raised to it also binds the uncut protein, and reported levels depend on which antibody was used ²

Beyond the body’s own use

• The vascular work is isolated tissue and animals: synthetic fragments from the start of chromogranin A relaxed constricted human saphenous vein, and that result from 1994 is still the anchor of the literature. No human study has followed it ¹
• Nothing is in trials and nothing is claimed for it. What a reader should take from the granin fragments is that activity in a dish is easy to show and hard to turn into a number in a patient ²