NERP-2

Where it comes from

Made in

Hypothalamus, posterior pituitary and the adrenal

Sent out by

With vasopressin; fasting raises it

Acts on

• Vasopressin neurons
• Orexin neurons of the lateral hypothalamus
• Islets (insulin, in vitro)

What it does

• Suppresses vasopressin release like NERP-1 ¹
• Increases food intake and locomotion through orexin ²
• Enhances glucose-stimulated insulin release in islets ³

In medicine

• No medicine copies it or blocks it, and it is not measured in people
• It has no identified receptor. Its feeding effect is abolished by an orexin receptor blocker, so what it binds first is still unknown ²

Beyond the body’s own use

• Nothing containing it is in trials, approved or obtainable outside the laboratory
• It is the more interesting half of the pair: as well as restraining vasopressin like NERP-1, it increases food intake and movement, and that effect disappears when orexin signalling is blocked, which places it upstream of the wake-and-feed system ²
• What is unknown is how one precursor coordinates three jobs. VGF yields NERP-1, NERP-2 and TLQP-21, which act on water balance, feeding and fat, and nothing is known about what decides which of them a cell makes ³