Histochemical observation of bovine spinal ganglia

Summary Morphologically, large oval cells, small oval cells and intermediate cells were distinguished among the nerve cells of the bovine spinal ganglion. — The nerve cells generally showed the prominent enzymatic reactions to SDH, NAD-, NADP-dependent MDH, GDH and NAD-dependent IDH.— Large cells reacted somewhat slightly to alpha-GDH, G-6-PDH and NADP-dependent IDH, while intermediate and small cells reacted strongly. LDH reaction of large and small cells was moderate and that of intermediate cells varying. — In general, to the dehydrogenases tested, intermediate cells were most stainable and small cells reacted in the varying degrees. Considerable reactions for dehydrogenases were present in the capsular cells especially in the case of NADP-dependent IDH and G-6-PDH. The nerve fibers were less stainable to the dehydrogenases. MAO activity was observed in the capsular cells, nerve fibers and a large number of the nerve cells. — AChE reaction of the nerve cells was various and that of the capsular cells negligible, while ChE activity was limited to the capsular cells. ACP activity in nerve and capsular cells was positive, and ALP activity was confined to the capsular cells and the capillary vessels. Intense ATPase activity was localized in the capsular cells, peripheral zone of the neuroplasm and the neurilemma.     

Mucopolysaccharides in the dog spinal cord and dorsal root ganglia. A histochemical study.

A histochemical study of mucopolysaccharides in the dog spinal cord and dorsal root ganglia is reported in this paper. The histochemical techniques used were the following: PAS, colloidal iron, toluidine blue (pH 5.4 and 3.5), thionine (pH 5.4 and 3.5) and alcian blue 8GX (pH 1 and 2.5). Some histological stains were used also. Two types of neurons could be observed in spinal cord sections stained with colloidal iron techniques. In some neuron a border line of mucosubstances could be seen. In the dorsal root ganglia, different patterns of Nissl bodies distribution in neurons were described. This different distribution of Nissl bodies is associated with different metachromatic colorations of neurons. By using the colloidal iron method, two types of neurons were also revealed in the dorsal root ganglia: some neurons are of a yellow, small-sized and star-shaped type and others are of a light green, larger and round-shaped type. Mucosubstances in the endoneurium and perineurium of nerve fibers, in the Ranvier nodules and in the Schmidt-Lantermann incisures were observed. The possibility that the functional rhythm in some cases might be responsible for the difference in coloration between the dorsal root ganglia neurons is suggested.     

Influence of intrauterine asphyxia on the development of spinal ganglia

In 17- and 18-day-old rat embryos and in 10-, 30-day-old newborn rats, the development of the spinal ganglia neurons was investigated under normal conditions and after intrauterine asphyxia. It was stated that increase in the profile field of the neuronal body development proceded differently before and after birth. Before birth, the most intensive growth was noted in large ganglial cells, while after birth--in middle and especially small cells. It was stated that embryos subjected to asphyxia in the last fourth of their intrauterine life suffered from chronic disorders in their neuronal cells, their intensity increasing with time reaching maximum to the first month of life. This process involved mainly the cells of middle and small size.     

Development of satellite-neuron relations in the spinal ganglia of the rat

Cerebrospinal ganglia of 11-, 13-, 15-, 18- and 20-day-old embryos have been studied light- and electron-microscopically. On the 11th day of anlage the ganglia are presented exclusively as neuroblasts: the satellite-cells are formed later from lemmoblasts that install into the ganglion on the 13th-15th days both from the surrounding mesenchyme and from the developing roots and trunklets of the cerebrospinal nerves. In the ganglion they undergo proliferation and further differentiation. On the 15th day simple satellite-neuron interrelationships are formed: one satellite-cell is tightly connected with perikaryons of some neuroblasts and young neurons. On the 18th day around some neurons a double layered capsule is formed from the satellite-cells. Multilayered tunics are formed only on the 10th-15th day after birth. During the process of the capsule formation an unusual reactive character of the satellite-neuron interrelationships is revealed, it is manifested as, performed by the satellite-cells, an active microphagocytosis of the perikaryon cytoplasmic processes and the initial segment of the sensitive neuron main process. In embryogenesis the lemmocyte-axon interrelationships develop earlier than the satellite-neuronal ones.     

Representation of skeletal muscles in the spinal ganglia of the cat

In 5 experimental and 3 control cats the m. extensor digitorum longus (MEDL) has been extirpated in both extremities. In 10 days the cats are sacrificed with a lethal dose of pentobarbital. In the spinal ganglia, which are supposed to innervate the MEDL, the state of chromatophilic substance is investigated. The amount of neurons with chromatolysis is determined. A new source of the MEDL sensitive innervation--ganglion SIII is revealed. Certain asymmetry in the MEDL ganglia innervation is noted in the left and right sides.     

Postischaemic changes in the satellite cells of dog spinal ganglia

Changes in the satellite cells of the spinal ganglia were studied in dogs after ischaemia induced by repeated 40 min ligation of the abdominal aorta, followed by 1-6 days' survival. The nuclei of the satellite cells were hypertrophic, with a tendency to lobulation, and contained conspicuous nucleoli. The mitochondria were enlarged and denser, but their internal structure remained intact. The Golgi complex displayed signs of hyperplasia and an increase in the vesicular component. An increase in the number of filaments and free ribosomes could be seen in the cytoplasm of the satellite cells. There was also a remarkable increase in the endoplasmic reticulum, especially after six days' survival. The qualitative and quantitative changes testify to stimulation of the metabolic activity of the satellite cells in the postischaemic period.     

Effects of vasopressin on the somatic membrane of spinal ganglia neurons

Intracellular recording from the soma of 68 sensory neurons was performed during experiments on perfused cerebrospinal ganglia (CSG) isolated from 22- to 36-day-old rats. Application of vasopressin (VP) to the CSG produced a response in 59 cells (or 87.76%). Depolarization was noted in 67.8% of those responding, two-stage response in 16.95%, and hyperpolarization in 15.25%. All responses were dose-dependent and reversible. Membrane resistance (R_m) following depolarization declined but increased following hyperpolarization. Application of VP produced a lengthening of action potentials (AP) and a decline both in AP amplitude and after-hyperpolarization. A correlation was revealed between the biophysical properties of CSG neurons and the pattern of their response to VP. Neurons with a slow velocity of axonal conductance, protracted AP, and high R_m (small cells) had the lowest sensitivity threshold to VP at a concentration of 1·10^–11 M and responded with prolonged high-amplitude depolarizing potentials. Cells with a high velocity of axonal conductance, short-lasting AP, and low R_m responded to VP at a concentration of 1·10^–8 M, although response was occasionally lacking even at a concentration of 1·10^–6 M. Depolarization was more short-lived in these neurons and characterized by lower amplitude; cases of hyperpolarization were sometimes observed. Findings from our study would indicate that VP exerts an effect on the soma or primary sensory neurons, acting preferentially on small CSG cells.A. A. Bogomolets Institute of Physiology, Academy of Sciences of the Ukrainian SSR, Kiev. Translated from Neirofiziologiya, Vol. 20, No. 6, pp. 801–808, November–December, 1988.