IMPAIRED NITRERGIC RELAXATION OF THE SPHINCTER OF ODDI OF HYPERLIPIDEMIC RABBITS

Field stimulation relaxed the sphincter of Oddi muscle rings of the ra bbit after incubation with phentolamine, oxprenolol and atropine (all 1 mu M). The relaxation was blocked by N-G-nitro-L-arginine methyl est er (30 mu M) and was reversed by 3 mM L-arginine but not D-arginine. S phincter of Oddi preparations from hypercholesterolaemic rabbits exhib ited contractions under the same conditions. We conclude that nitrergi c relaxation is impaired in the sphincter of Oddi from hypercholestero taemic rabbits.