Fictive locomotion in the lamprey; a comparison using bicarbonate and HEPES buffers.

Fictive locomotion in the lamprey, elicited by N-methyl-DL-aspartate or D-glutamate, was compared in two buffer solutions, one using bicarbonate, the other using HEPES. No differences were observed in burst proportion, cycle length, or phase lag per segment between these buffers solutions. These data indicate that HEPES-buffered artificial cerebrospinal fluid, which does not require gassing with carbon dioxide to maintain pH, may be a suitable alternative to bicarbonate-buffered artificial cerebrospinal fluid.