Figure 2. Effect of hypoglycaemia on the [³H]CA released from rat carotid body evoked by mild (10% O₂) hypoxia.

A, the time course of the release of [³H]CA in three individual CBs incubated with solutions equilibrated with 10% O₂. Control CB (continuous line) was continuously incubated with solutions containing 5.5 mm glucose and experimental CBs (dashed lines) were similarly incubated except for the marked periods where the glucose concentration was diminished. In one of the experimental CBs (dashed line) the concentration of glucose was reduced to 3 mm between minutes 20 and 30, to 1 mm between minutes 50 and 60 and to 0 mm between minutes 80 and 90. In the other experimental CB the sequence of low glucose incubation was reversed. In B–D each column represents the [³H]CA present in each 10 min collected fraction corresponding to the mean (+s.e.m.; n = 6) release in control and experimental CBs.