Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0042963 (vomiting)
 31,883 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The emetic and antiemetic effects of opioid agonists were studied in awake dogs. The mu-agonists morphine, fentanyl and methadone, in sedative doses, prevented the emetic response to apomorphine and copper sulphate; only morphine induced emesis, at doses lower than those required to prevent emesis. The delta-agonist [D-Ala2,Met5]enkephalinamide (DALA) and [Leu5]enkephalin induced emesis in some of the dogs studied but had no antiemetic activity. The kappa-agonists bremazocine and ethylketocyclazocine (EKC) did not induce emesis but, at sedative doses, prevented the emetic response to apomorphine. The emetic effect of DALA was antagonized by naloxone in some dogs; the antiemetic effect of morphine, bremazocine and EKC was blocked by both naloxone and MR 2266. The non-opioid sedatives diazepam, phenobarbital and xylazine, administered in sedative doses, did not prevent apomorphine-induced emesis. Our results suggest that a delta-receptor is involved in the emetic effect and a mu- and/or or kappa-receptor in the antiemetic effect of opioids.
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PMID:Emetic and antiemetic effects of opioids in the dog. 302 91

Those structural features of enkephalins (ENK) responsible for in vitro organ bath and receptor binding activity have been investigated in detail in the conscious, chronically instrumented dog. Amide analogs of Leu5-ENK display reduced activity, which is restored by D-Ala2 substitutions. N-terminal L-Tyr is required for full opiate activity. Although proven delta-receptor agonists do appear generally more active, distinctions made in vitro between mu and delta binding are not apparent in the complex hemodynamic responses which occur in the intact unanesthetized dog. The amphibian skin peptide dermorphin, which contains D-Ala2, elevates heart rate, systemic arterial pressure, and induces vomiting with near maximal activity at a dose of 1.0 microgram/kg; this activity is inhibited by naloxone. This activity, coupled with dermorphin's apparent presence in mammalian tissue, suggests that it may represent another peptide factor in cardiovascular regulation. In the conscious dog, ENK elevate heart rate and systemic arterial pressure; this activity does not appear to be fully explained by in vitro receptor models.
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PMID:Enkephalin analogs and dermorphin in the conscious dog: structure-activity relationships. 716 98