Haloperidol treatment increases the biosynthesis and release of endorphins in guinea-pig ileum.
Guinea-pigs treated acutely (5 mg kg-1 i.p.) and chronically (2 or 5 mg kg-1 day-1 for 4 days) with haloperidol, show an increase of the inhibitory response produced by electrical stimulation at 10 Hz of the ileum myenteric plexus-longitudinal muscle (MPLM) preparation. The response can be reversed by the specific narcotic antagonist naloxone (5 X 10(-7) M), which suggests that the increase in the response produced by haloperidol is mediated by release of endorphins. When haloperidol-treated guinea-pigs received cycloheximide (24 and 12 h before death), there was a substantial decrease in the response indicating that the biosynthesis and release of endorphins are increased by haloperidol.
D000818:Animals; D003513:Cycloheximide / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004723:Endorphins / Q000378:metabolism*; D004744:Enkephalin, Methionine / Q000494:pharmacology; D005260:Female; D006168:Guinea Pigs; D006220:Haloperidol / Q000494:pharmacology*; D007082:Ileum / Q000378:metabolism*; D066298:In Vitro Techniques; D008297:Male; D009270:Naloxone / Q000494:pharmacology; D011954:Receptors, Dopamine / Q000187:drug effects
D004723:Endorphins; D011954:Receptors, Dopamine; D009270:Naloxone; D004744:Enkephalin, Methionine; D003513:Cycloheximide; D006220:Haloperidol