Abstract
The effects of N‐(1‐phenylcyclohexyl) piperidine (PCP) and related drugs on isolated intact segments of the guinea‐pig ileum were determined. 1–1‐(2‐Thienyl) cyclohexylpiperidine (TCP), PCP and ketamine decreased the height of electrically induced contractions (0.1 Hz) of intact segments of isolated guinea‐pig ileum. Thirty to forty percent of the inhibition of contraction height (0.1 Hz) was reversed by pretreatment with the pure narcotic antagonist, naloxone. This naloxone‐reversible component showed cross‐tolerance with morphine. PCP pretreatment caused a shift to the right in the dose‐response curve to acetylcholine (ACh) that was not parallel with the control dose‐response curve. Thus PCP does not interact with the muscarinic cholinoceptor in a strictly atropine‐like competitive fashion. Binding sites for [3H]‐PCP were detected in homogenates of the guinea‐pig longitudinal muscle‐myenteric plexus preparation. The affinity constants and the rank order of potencies of various PCP derivatives competing with [3H]‐PCP for binding suggest that these binding sites are very similar to those found in the central nervous system. These data suggest that the guinea‐pig isolated ileum may be used as an in vitro system for studying the mechanism of action of phencyclidines. 1982 British Pharmacological Society
Original language | English (US) |
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Pages (from-to) | 261-267 |
Number of pages | 7 |
Journal | British Journal of Pharmacology |
Volume | 75 |
Issue number | 2 |
DOIs | |
State | Published - Feb 1982 |
ASJC Scopus subject areas
- Pharmacology