One of the studies showed that blockade of opioid receptors with naltrexone reduced liver fibrosis and hepatic stellate cell (HSC) activation, along with reduced plasma ALP (Alkaline Phosphatase) and ALT (Alanine Transaminase) activity, but without significantly affecting liver inflammation in BDL rats (rats with ligated bile ducts) [27]. The gene discussed is GPT; the disease is Hepatic fibrosis.