Table 2. 5-HT (10 mmol/liter) induced contractions of isolated guinea pig ileum.

Compound	Dose, mmol/dl	Contraction rate, %
Before		100
Vehicle†		105 ± 2
l-Lysine	0.007	109 ± 4
	0.07	90 ± 3*
	0.7	75 ± 5**
l-Leucine	0.07	103 ± 5
	0.7	98 ± 6

Data are means ± SEM of three animals. *, P < 0.05; and **, P < 0.01 (significant difference from vehicle).

^†Distilled water (100 μl/10 ml).