title: Purine nucleoside--mediated immobility in mice: reversal by antidepressants.
abstract: In the forced swimming-induced immobility (despair) test model, adenosine, and 2-chloroadenosine treatment prolonged the immobilization period in mice. Dipyridamole, which is known to inhibit adenosine uptake, potentiated the adenosine effect. The purinoceptor antagonists caffeine and theophylline blocked purine nucleoside-induced enhancement of immobilization. Tricyclic antidepressants such as imipramine and desipramine, the MAO inhibitor tranylcypromine, and amphetamine, a psychostimulant, reversed purine nucleoside-induced immobility. On the other hand, quipazine, fluoxetine, and amitriptyline failed to reverse purine nucleosides-induced prolongation of immobility. None of the antidepressants in the doses investigated had any effect by themselves. Reserpine also prolonged forced swimming-induced immobility in mice. The antidepressants fluoxetine and quipazine, but not methylxanthine pretreatment, reversed reserpine-induced immobility in this test model. These results indicate that adenosine and 2-chloroadenosine probably reduce norepinephrine outflow through their action on presynaptic purinoceptors on noradrenergic neurons and thereby cause prolongation of immobility in animals.
authors.forename: S K
authors.initials: SK
authors.lastname: Kulkarni
authors.forename: A K
authors.initials: AK
authors.lastname: Mehta
mesh_terms: D015762:2-Chloroadenosine; D000241:Adenosine / Q000031:analogs & derivatives* / Q000037:antagonists & inhibitors / Q000633:toxicity*; D000320:Adrenergic Fibers / Q000187:drug effects; D000818:Animals; D000928:Antidepressive Agents / Q000494:pharmacology*; D003866:Depressive Disorder / Q000139:chemically induced*; D004195:Disease Models, Animal; D005260:Female; D006801:Humans; D008297:Male; D051379:Mice; D017981:Receptors, Neurotransmitter / Q000187:drug effects; D011983:Receptors, Purinergic
chemical_list: D000928:Antidepressive Agents; D017981:Receptors, Neurotransmitter; D011983:Receptors, Purinergic; D015762:2-Chloroadenosine; D000241:Adenosine