Brain research
-
Comparative Study
Organization of neurons forming the femoral, sciatic, common peroneal and tibial nerves in rats and monkeys.
Our study shows that, using Elliott's method, 6 major groups of neurons can be identified in the lumbosacral cord segments of both monkeys and rats. These are the medial (m), ventromedial (vm) anterolateral (al), central (c), posterolateral (pl) and post-posterolateral (ppl) groups; they are, except for minor differences, similarly arranged in neonatal, immature, and mature monkeys and rats. Localization of neurons by the horseradish peroxidase method reveals that the sciatic nerve (ScN) neurons are distributed to L4-L7 segments in all monkeys studied and also to the rostral part of S1 segment in some monkeys. ⋯ There is also no significant difference in the counts of labeled right and left ScN neurons. The histograms showing the number of labeled ScN neurons against their diameters are very similar in both rats and monkeys. In both animals, the diameters of ScN neurons vary widely between 3 and 53 microns.
-
In decerebrate-decerebellate cats, dorsal column stimulation (DCst) rostral to selective dorsal funicular cuts, to prevent antidromic activation of afferent DC fibers, produced primary afferent depolarization and modulated reflexes at the lower spinal level. These findings indicate the importance of a DC-brainstem-spinal loop in explaining the effects of DC stimulation in man and experimental animals.