Example 3
Preparations of full-thickness colonic segments (˜1.5 cm) were allowed to equilibrate in 37° C. Kreb's-jacketed organ baths with their distal ends opening to a pressure transducer and maintained under basal pressure of 5-cm column of vehicle (RL). The proximal end was closed during pressure recordings but opened to allow luminal infusion of vehicle or tryptamine in solution (100 μM, 1 mM and 3 mM; 10 minutes per treatment; n=5-7 mice).
Contractile frequency was not significantly different comparing tryptamine treatments with vehicle controls; however, there was a trend toward increased frequency in segments treated with luminal 1 mM tryptamine compared to controls (5.9±0.8 vs 4.1±0.6; P=0.15). Mean contractile amplitude and contractile magnitude, as measured by area under the curve, were also not significantly different between control (vehicle alone) and any of the tryptamine concentrations examined. Contractile duration, measured at half amplitude, was not significantly different between vehicle controls and any of the luminal tryptamine treatments.
