Endogenous opiates modulate release of growth hormone in response to electroacupuncture

The effect of electroacupuncture on serum growth hormone levels was investigated in 5 normal subjects and in 10 patients with chronic musculoskeletal pain. Serum growth hormone did not change in the normal subjects but there was an approximate 5-fold increase in the chronic pain subjects. This effect was partially inhibited by prior administration of the opiate antagonist naloxone, suggesting that the rise in growth hormone was mediated via release of central nervous system opioids.