Central cholinergic mechanisms in L-DOPA induced hyperactive urinary bladder of the rat.
The involvement of central and peripheral cholinergic structures in the mediation of a centrally induced hyperactive urinary bladder response to L-2,3-dihydroxyphenylalanine (L-DOPA), after peripheral decarboxylase inhibition, registered by a cystometric procedure, has been analysed pharmacologically in anaesthetised rats. The urinary bladder response to L-DOPA was unchanged after blockade of cholinergic receptors with methylscopolamine, diminished after atropine and totally inhibited after hexamethonium. In addition, activation of muscarinic receptors in the pontine-mesencephalic brain region with oxotremorine after methylscopolamine pretreatment generates a hyperactive urinary bladder response, mediation of which seems to be independent of endogenous catecholamine stores. It is suggested that cholinergic receptors in the pontine-mesencephalic brain region are of importance for regulation of urinary bladder function in the rat. Furthermore, the bladder hyperactivity induced by L-DOPA might be propagated via muscarinic receptors in this brain area, and mediated peripherally via cholinergic receptors in the autonomic ganglia, but in the bladder detrusor via non-cholinergic receptors.
D000818:Animals; D001285:Atropine / Q000494:pharmacology; D001921:Brain / Q000187:drug effects; D002118:Calcium / Q000037:antagonists & inhibitors; D006584:Hexamethonium Compounds / Q000494:pharmacology; D007980:Levodopa / Q000494:pharmacology*; D008297:Male; D019832:N-Methylscopolamine; D010095:Oxotremorine / Q000494:pharmacology; D010646:Phentolamine / Q000494:pharmacology; D051381:Rats; D011941:Receptors, Adrenergic / Q000187:drug effects; D011950:Receptors, Cholinergic / Q000187:drug effects*; D012110:Reserpine / Q000494:pharmacology; D012602:Scopolamine Derivatives / Q000494:pharmacology; D013015:Sotalol / Q000494:pharmacology; D001743:Urinary Bladder / Q000294:innervation*
D006584:Hexamethonium Compounds; D011941:Receptors, Adrenergic; D011950:Receptors, Cholinergic; D012602:Scopolamine Derivatives; D007980:Levodopa; D010095:Oxotremorine; D001285:Atropine; D012110:Reserpine; D013015:Sotalol; D002118:Calcium; D019832:N-Methylscopolamine; D010646:Phentolamine