Page "Endorphins" Paragraph 6

* Around the same time, in the calf brain, Rabi Simantov and Solomon H. Snyder of the United States found what Eric Simon ( who independently discovered opioid receptors in the brain ) later termed " endorphin " by an abbreviation of " endogenous morphine ", meaning " morphine produced naturally in the body ".

Importantly, recent studies have demonstrated that diverse animal and human tissues are in fact capable of producing morphine itself, which is not a peptide.