Put it this way , Lesnar is considered a huge draw by the WWE . Mcgregor is a bigger name in general than Lesnar ever was . He ' s the biggest draw in UFC history , it would be a great idea business wise for WWE to bring him in for an appearance . <| sep |> This makes me think of receptor downregulation . When you consume a massive amount of drug molecule your brain cells will try to adapt to their new environment , i . e . an environment with an abundance of drug molecules present . The cell will reduce the number of receptors on the surface in an attempt to normalize signaling and response . Less receptors , less response . So no , your receptors haven ' t turned off , there just isn ' t as many of them . The cell will also upregulate receptors when it needs a bigger response . I don ' t know if this is the case but this is a pretty simple biological response that could come from an overdose . It usually is seen in long term habitual usage but can also happen in single events .