GHRH

Where it comes from

Made in

The arcuate nucleus of the hypothalamus; also the pancreas and some tumours

Sent out by

In pulses, alternating with somatostatin; sleep, exercise, hypoglycaemia and ghrelin raise it

Acts on

• Pituitary somatotrophs

What it does

• Drives the synthesis and pulsed release of growth hormone
• Keeps the somatotrophs alive and numerous; its receptor’s loss causes dwarfism
• Pancreatic and carcinoid tumours that secrete it cause acromegaly

In medicine

• Tesamorelin (2010), a GHRH analogue, reduces abdominal fat in HIV-associated lipodystrophy ¹
• Sermorelin (GHRH 1-29) was approved for growth hormone deficiency and for testing; its maker discontinued it in 2008, not for reasons of safety or effectiveness
• GHRH plus arginine is a test of growth hormone reserve

Beyond the body’s own use

• Tesamorelin has been taken further in HIV: in a randomised trial of 61 patients it cut liver fat by about a third against placebo, without worsening glucose control ²
• CJC-1295, a long-acting GHRH analogue, has one published human study, a phase 1 in healthy adults where a single injection kept growth hormone and IGF-1 raised for a week or more; it has never been approved anywhere ³
• Sermorelin and CJC-1295 are prescribed by compounding and “anti-ageing” clinics and passed around for muscle and fat loss; compounded and unapproved preparations are not reviewed for safety, effectiveness or quality, and no trial supports either use
• GHRH and its analogues, with CJC-1293, CJC-1295, sermorelin and tesamorelin named among them, are banned in sport at all times under section S2 of the Prohibited List ⁴