Smooth muscle cells were isolated from the fundus of the canine gallbladder and examined for the presence of opioid receptors. The cells contracted in a concentration-dependent manner in response to three opioid peptides (Met-enkephalin, dynorphinl-13 and Leu-enkephalin), which are known derivatives of opioid precursors present in myenteric neurons of the gut. The order of potency was Met-enkephalin > dynorphinl-13 > Leu-enkephalin. The contractile response to opioid agonists was selectively inhibited by opioid antagonists (naloxone and Mr2266) but not by muscaarinic, CCK/gastrin or tachykinin antagonists. Equivalent responses to the three opioid peptides exhibited differential sensitivity to preferential antagonists of μ (naloxone) and κ (Mr2266) opioid receptors consistent with the presence of the three main types of opioid receptors (μ, δ and κ) on canine gallbladder muscle cells. © 1988.
CHARACTERIZATION OF OPIOID RECEPTORS ON ISOLATED CANINE GALLBLADDER SMOOTH-MUSCLE CELLS / Severi, Carola; J. R., Grider; G. M., Makhlouf. - In: LIFE SCIENCES. - ISSN 0024-3205. - 42:23(1988), pp. 2373-2380. [10.1016/0024-3205(88)90191-9]
CHARACTERIZATION OF OPIOID RECEPTORS ON ISOLATED CANINE GALLBLADDER SMOOTH-MUSCLE CELLS
SEVERI, Carola;
1988
Abstract
Smooth muscle cells were isolated from the fundus of the canine gallbladder and examined for the presence of opioid receptors. The cells contracted in a concentration-dependent manner in response to three opioid peptides (Met-enkephalin, dynorphinl-13 and Leu-enkephalin), which are known derivatives of opioid precursors present in myenteric neurons of the gut. The order of potency was Met-enkephalin > dynorphinl-13 > Leu-enkephalin. The contractile response to opioid agonists was selectively inhibited by opioid antagonists (naloxone and Mr2266) but not by muscaarinic, CCK/gastrin or tachykinin antagonists. Equivalent responses to the three opioid peptides exhibited differential sensitivity to preferential antagonists of μ (naloxone) and κ (Mr2266) opioid receptors consistent with the presence of the three main types of opioid receptors (μ, δ and κ) on canine gallbladder muscle cells. © 1988.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
