EFFECTS OF 2 ANTICHOLINERGIC DRUGS, TROSPIUM CHLORIDE AND BIPERIDEN, ON MOTILITY AND EVOKED-POTENTIALS OF THE ESOPHAGUS

Background: Anticholinergic drugs are known to impair the motor functi on of the oesophagus but their effects on the oesophageal afferent pat hways are unknown. Aim: To determine the effects of a peripherally-act ing (trospium chloride) and a centrally-acting (biperiden) anticholine rgic drug on the motility and the evoked potentials of the oesophagus, Methods: Nine healthy Volunteers were randomized to receive 1.2 mg tr ospium chloride (TC), 5 mg biperiden (BIP) or saline i.v. Primary peri stalsis was elicited by swallowing a 5 mi, water bolus and secondary p eristalsis by insufflation of 20 mL air, 10 times each. Oesophageal po tentials were evolved by electrical stimulation in the distal and prox imal oesophagus (30 stimulations at 0.4 Hz, two runs). Results: Both a nticholinergic drugs reduced by a similar amount the contraction ampli tudes (TC 17 mmHg, BIP 25 mmHg, saline 67 mmHg; P < 0.01) and the rate of secondary contractions (TC 60%, BIP 70%, saline 95%; P < 0.01). In contrast, only biperiden prolonged the latencies of the evolved poten tials (N1 peak, distal oesophagus: BIP 191 ms, TC 102 ms, saline 101 m s; P < 0.01; P1 peak: BIP 322 ms, TC 161 ms, saline 144 ms; P < 0.01). Conclusions: Both anticholinergic drugs depress oesophageal motility, but only the centrally-acting anticholinergic drug biperiden modifies the oesophageal evoked potentials, suggesting a central cholinergic t ransmission of the oesophageal afferent pathways.