Substance P and the NK1 receptor are widely distributed in the brain and are found in brain regions that are specific to regulating emotion (hypothalamus, amygdala, and the periaqueductal gray).
A substancia P e o receptor NK1 están amplamente distribuídos no cerebro e encóntranse especificamente en rexións do cerebro que regulan a emoción (hipotálamo, amígdala, e a substancia gris periacuedutal).