They all contain the same genome and can activate the same pathways. Same way that your skin and airways can make histamine as an inflammitory signal while your midbrain makes it as a sleep suppressing neurotransmitter (which is why most antihistamines make you sleepy). Genes and pathways and enzymes are quite often not organ specific.
How come very different organs in mammals can make the same hormones? ie. testes, ovaries, adrenals all make testosterone
They all contain the same genome and can activate the same pathways. Same way that your skin and airways can make histamine as an inflammitory signal while your midbrain makes it as a sleep suppressing neurotransmitter (which is why most antihistamines make you sleepy). Genes and pathways and enzymes are quite often not organ specific.