The Company of Biologists

Table 1.

Kinetic constants for transmural ³H-l-histidine transport in the presence and absence of 20 μmol l^–1 zinc and 100 μmol l^–1l-leucine

Perfusate	K_m (μmol l^—1)	J_max (pmol cm^—2 min^—1)
l-Histidine control	6.2±0.8	0.09±0.004
l-Histidine + Zinc	19±3^{^*}	0.28±0.02^{^*}
l-Histidine + Zinc + Leucine	4.5±1.7^{^†}	0.08±0.01^{^†}

Perfusate	K_m (μmol l^—1)	J_max (pmol cm^—2 min^—1)
l-Histidine control	6.2±0.8	0.09±0.004
l-Histidine + Zinc	19±3^{^*}	0.28±0.02^{^*}
l-Histidine + Zinc + Leucine	4.5±1.7^{^†}	0.08±0.01^{^†}

Values are means ± s.e.m. of three replicates per point.

Significantly different (P<0.01) than control

significantly different (P<0.01) than l-His + Zn treatment