TY  - JOUR
A1  - Paakkari, P.
A1  - Paakkari, I.
A1  - Feuerstein, G.
A1  - Sirén, Anna-Leena
T1  - Evidence for differential opioid µ\(_1\)- and µ\(_2\)-receptor regulation of heart rate in the conscious rat
N2  - The possibility that \(\mu\)Opioid-induced tachycardia and bradycardia could be mediated by different subtypes of the \(\mu\)·receptor was studied in conscious Sprague-Dawley rats. The selective \(\mu\)·receptor agonist dermorphin and its analog, TAPS (Tyr-o-Arg-Phe-sarcosine), a putative \(\mu _1\)-receptor agonist, were given centrally. Tyr-o-Arg-Phe-sarcosine increased the heart rate, the response being inversely correlated to the dose (an increase of 71 ± 22, 49 ± 14 and 30 ± 17 beats/min at doses of 0.3, 3 and 30 pmol, respectively). Dermorphin induced less clear changes in heart rate (maximum increase of 39 ± 14 beats/min at the dose of 1 pmol). Aftertreatment with the Jl 1-selective antagonist naloxonazine (NAZ), TAPS 30 pmol and dennorphin I pmol decreased heart rate by -22 ± 10 and -24 ± 7 bpm, respectively. The bradycardic effect oflarger doses of dennorphin was potentiated by NAZ (from -25 ± 8 to -97 ± 22 bpm) but abolished by the non-selective antagonist naloxone. These data suggest that the high affinity \(\mu _1\)-opioid receptors mediate tachycardic responses and \(\mu _2\)-receptors mediate bradycardic responses.
KW  - Neurobiologie
KW  - dennorphin
KW  - naloxonazine
KW  - naloxone
KW  - heart rate
KW  - blood pressure
KW  - µ·Opioid receptor subtypes
Y1  - 1992
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-63017
ER  -