title: The direction of opiodid agonists towards mu-, delta- and epsilon-receptors in the vas deferens of the mouse and the rat.
mesh_terms: D000818:Animals; D066298:In Vitro Techniques; D008297:Male; D051379:Mice; D009119:Muscle Contraction / Q000187:drug effects*; D009130:Muscle, Smooth / Q000187:drug effects; D009294:Narcotics / Q000494:pharmacology*; D051381:Rats; D011957:Receptors, Opioid / Q000187:drug effects*; D013045:Species Specificity; D014649:Vas Deferens / Q000187:drug effects*
chemical_list: D009294:Narcotics; D011957:Receptors, Opioid