gamma-Aminobutyric acid system in isolated dorsal and ventral horn neurons from bovine spinal cord.

In order to search for the relationship between the structure and the function of the nervous system, the spinal cord provides suitable material. We devised a procedure for isolation of large ventral and small dorsal horn neurons. Then we examined the gamma-aminobutyric acid (GABA) system in both neurons isolated using our procedure. Glutamic decarboxylase (GAD) activity in dorsal horn neurons was much higher than that in ventral horn neurons. Further, GABA uptake activity by the dorsal horn neurons was also somewhat higher than that by the ventral horn neurons, although some properties of GABA uptake were found to be almost the same in both neuronal fractions. However, we could not find any difference of GABA-alpha-ketoglutarate transaminase (GABA-T) activity between the dorsal and ventral horn neurons. These results suggest that GAD and GABA uptake may be indicators for cell specificity to some extent.