LONG-TERM DISPOSITION OF PHENCYCLIDINE IN MICE

  • 1 January 1982
    • journal article
    • research article
    • Vol. 10  (2) , 189-193
Abstract
The disposition of 3H-phenacyclidine (PCP) [an abused drug], as well as total metabolites, was studied in mice up to 21 days after either i.v. or oral administration. Thirty minutes after either i.v. or oral administration the highest concentrations of 3H-PCP were found in stomach. The next highest levels were in fat (i.v.), liver (oral) and intestines (oral) and the lowest levels were found in brain and plasma (i.v. and oral). Twenty-four hours later, the levels of 3H-PCP in all tissues were < 2% of the concentrations after 30 min. After 3 days, the only detectable levels were in fat and were < 1% of the 30-min levels. Trace quantities of 3H-PCP were detected in fat at 7, 14 and 21 days. The disposition of total metabolites differed from that of 3H-PCP in that total metabolite levels were highest in stomach, liver and intestines 30 min after administration of 3H-PCP by both routes. After 24 h the concentration of total metabolites in all tissues far exceeded that of 3H-PCP. The highest concentration of metabolites remained in liver, stomach and intestines for 24 h, but after 3 days the levels in stomach and intestines fell considerably. Metabolite levels were sustained in lung and liver up to 14 days and in lung up to 21 days. Mice were also treated with 7 daily gavages of 3H-PCP to determine the extent of 3H-PCP and metabolite accumulation. 3H-PCP was found only in fat 7, 14 and 21 days after the last treatment, but these levels were quite low. Metabolite levels in lung and liver at all time points were 5-10 times greater than those following acute treatment. 3H-PCP does not appear to be sequestered to an appreciable extent in any tissue in mice, whereas metabolites do accumulate in lung and liver for long periods of time.