Table 1. Glutamate Release from Rat, Mouse, and Guinea Pig Cerebrocortical Synaptosomes

* Followed by 95% confidence interval. Obtained by fitting the data to a four-parameter logistic concentration–response function with maximal inhibition (E^max) of 75% for isoflurane and 100% for propofol.

† Data from assays performed at concentrations close to the minimum alveolar concentration (MAC) of isoflurane in rat (0.35 mm 33; n = 3) compared with control values in the absence of anesthetic (n = 11).

‡ Data from assays performed at 10–12 μm propofol (free concentration; ∼5 times the EC⁵⁰in tadpoles 34; n = 4) compared with control values in the absence of anesthetic (n = 11).

§P < 0.05 versus  control (no anesthetic) by analysis of variance with Newman-Keuls post hoc  test.

NS = slope not significantly different from zero by linear regression.