Fig. 7.

Influence of methysergide and WB-4101 on variables of phrenic discharge (see Fig. 3 legend) in gasping in a control group of wild-type and normal mice. Control values are for preparations in which ischemic gasping was produced without addition of methysergide or WB-4101. Values are reproduced from Fig. 3, in which f fell significantly and peak rose significantly in gasping compared with eupnea. Frequencies were slightly higher and peak heights were lower after addition of methysergide or WB-4101 in gasping than in control preparations in gasping. Number of preparations is as follows: n = 15 for control, n = 3 for 1 μM methysergide, 3 μM methysergide, 0.5 μM WB-4101, and 1 μM WB-4101; n = 8 for 2 μM methysergide and 2 μM WB-4101.