Morphine and opioid peptides selectively inhibit the non-cholinergically mediated neurogenic contraction of guinea-pig isolated bronchial muscle
-
- Yuichiro Kamikawa
- Department of Pharmacology, Dokkyo University School of Medicine , Mibu, Tochigi 321-02,
-
- Yasuo Shimo
- Department of Pharmacology, Dokkyo University School of Medicine , Mibu, Tochigi 321-02,
この論文をさがす
説明
<jats:title>Abstract</jats:title><jats:p>The experiments examine the actions of morphine and opioid peptides on the responses evoked by electrical field stimulation or by acetylcholine (ACh) and substance P (SP) in guinea-pig bronchial strip chain. Electrical field stimulation evoked a biphasic contraction, consisting of a cholinergically mediated fast contraction followed by a non-cholinergically mediated slow contraction. Morphine and opioid peptides caused a concentration-dependent inhibition in the height of the non-cholinergic contraction. The order of inhibitory activity was BW443C > dynorphin > morphine > β-endorphin > leucine-enkephalin > methionine-enkephalin. Cholinergically mediated contractions were less potently inhibited by these opioids. Submaximal contractions of bronchial muscle evoked by exogenous ACh (2 μM) or SP (02 μM) were not inhibited by morphine (100 μM) or opioid peptides (3–10 μM), rather, they were augmented. The results indicate that in guinea-pig isolated bronchial muscle, morphine and opioid peptides can selectively inhibit excitatory non-cholinergic neurotransmission via prejunctional opioid receptors.</jats:p>
収録刊行物
-
- Journal of Pharmacy and Pharmacology
-
Journal of Pharmacy and Pharmacology 42 (3), 214-216, 1990-03-01
Oxford University Press (OUP)