NEURAL CONTROL OF THE GALLBLADDER - AN INTRACELLULAR STUDY OF HUMAN GALLBLADDER NEURONS

Background/Aims: Gallbladder neurons are important governors of gallbl adder function. In animal models, gallbladder ganglia can be regulated both by neural and hormonal inputs. The purpose of this study was to demonstrate the feasibility of obtaining recordings from human gallbla dder neurons. Methods: Human gallbladders (n = 33) were bathed in oxyg enated Krebs solution (37 degrees C) containing the vital fluorescent stain 4-Di-2-ASP to localize the ganglia. Cells were characterized usi ng conventional intracellular recording techniques, Results: The mean resting membrane potential of human gallbladder neurons was -51.2 +/- 1.8 mV (n = 11), Depolarizing current pulses elicited only 1-4 spikes regardless of the amplitude or duration of the stimulus. After-spike h yperpolarizations had a mean duration of 144.5 +/- 19.2 ms (n = 10). A nodal break excitation was not recorded with hyperpolarizing current p ulses. Fiber tract stimulation elicited fast excitatory postsynaptic p otentials in all neurons tested. Conclusion: Intracellular recordings of human gallbladder neurons utilizing 4-Di-2-ASP are thus feasible, b ut are very problematic due to the density of connective tissue overly ing the ganglia, As human and guinea pig gallbladder neurons have simi lar basic electrical properties, the guinea pig may be an appropriate model for further electrophysiological studies into gallbladder diseas e.