Auto-tolerance to the endogenous opioids and sleep.
D001679:Biogenic Amines / Q000502:physiology*; D001921:Brain / Q000502:physiology*; D004298:Dopamine / Q000502:physiology; D004723:Endorphins / Q000502:physiology*; D004837:Epinephrine / Q000502:physiology; D006801:Humans; D009638:Norepinephrine / Q000502:physiology; D012701:Serotonin / Q000502:physiology; D012890:Sleep / Q000502:physiology*; D012894:Sleep Stages / Q000502:physiology
D001679:Biogenic Amines; D004723:Endorphins; D012701:Serotonin; D004298:Dopamine; D009638:Norepinephrine; D004837:Epinephrine