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Fig. 7. The effect of L-NAME on dose-dependent muscle contraction (as a
percentage of resting length) in response to 5HT. Treatment demibranchs (solid
circles/solid line) were exposed to 1x10-5 mol
l-1L-NAME for 15 min, and then both treatment and
control demibranchs (open circle/broken line) were exposed to increasing
concentrations of 5HT. Data were recorded using ultrasound, which allowed a
single demibranch to be used for an entire dose-response curve. Data consist
of paired demibranchs (three treatments, three controls) from three clams.