Scanning electron microscopic study on the lingual papillae in the Manchurian chipmunk, Tamias sibiricus asiaticus.

The superfacial structures of the tongues in the Manchurian Chipmunk, Tamias sibiricus asiaticus, were observed by scanning electron microscope. The tongues were long, tapering, narrow and thick with a long apical free portion and a small lingual prominence in the posterior half. In this animal, three circumvallate papillae were present in an inverted triangle, a minority of conical papillae on the pharyngeal part and parallel large conical papillae on the lateral border. The fungiform papillae were scanty on the dorsal surface. These characters suggested this animal was more primitive than the others in rodents.     

Retinal inputs and laminar distributions of the dorsal lateral geniculate nucleus relay cells in the eastern chipmunk (Tamias sibiricus asiaticus)

Summary Retinal inputs and their laminar distributions in the dorsal lateral geniculate nucleus (LGNd) of the eastern chipmunk (Tamias sibiricus asiaticus) were studied using histological and microelectrode recording techniques. A previous anatomical study (Fukuda et al. 1986a) indicated that the chipmunk LGNd had five laminae: contralaterally (contra) innervated lamina 1 and ipsilaterally (ipsi) innervated lamina 2 in its ventromedial part; laminae 3a (contra), 3b (ipsi) and 3c (contra) in its dorsolateral part. We have confirmed this finding in our present anatomical study and have also noted another ipsilaterally innervated thin lamina 0, medial to lamina 1. In our electrophysiological study, however, we were unable to record units from lamina 0 and to investigate it functionally. We recorded 232 units from laminae 1, 2 and the 3 complex, of which 95 were identified as Y-like, 46 as W-like, 15 as X-like, and 8 as mixed Y/W-like cells; the rest were either unclassified or visually unresponsive. In laminae 1 and 2, only Y-like and X-like cells were recorded, whereas in the laminae 3 complex W-like cells were recorded as well. The results suggest that the chipmunk laminae 1,2 and 3 complex correspond relatively well to the cat laminae A, A1 and C complex, respectively. In the chipmunk LGNd, however, there were more Y-like cells in laminae 1 and 2, and a few X-like cells of which some were color sensitive. Also, lamina 3a had a concentration of mixed-type cells with Y-like receptive field properties and W-like OX latencies. As for retinotopy, the dorsoventral transition of the contralateral visual field (laminae 1, 3a, 3c) is represented along the dorsoventral dimension of the chipmunk LGNd, whereas the temporonasal transition is represented in the rostrocaudal direction. Receptive field positions of the ipsilaterally innervated relay cells are limited to the central overlapping field of the contralateral visual fields of both eyes. Relay cells with visual fields having elevations of below -20° had relatively fast latency range and Ylike properties.     

Histochemical studies on the morphology of the Golgi apparatus and on the distribution of some enzymes concerned with carbodydrate metabolism in the rat cerebellum.

Detailed histochemical studies have been conducted on the distribution of various enzymes, including thiamine pyrophosphatase, alpha-glucan phosphorylase, hexokinase, glucose-6-phosphate dehydrogenase, aldolase, glycerol-3-phosphate dehydrogenase; menadion oxidoreductase, lactate dehydrogenase and succinate dehydrogenase in various components of the cerebellum of healthy adult male rats of the Wistar strain. The thiamine pyrophosphatase reaction showed the morphological patterns of the GOLGI apparatus characteristic for each kind of cells. The GOLGI apparatus is a simple network in stellate cells, but it can be classified into the same 5 categories in basket cells and GOLGI type II cells. The GOLGI apparatus in the latter 2 cell types appears to undergo cyclic changes. A few GOLGI type II cells have a supranuclear form (Type II) and some cells show disintegration and "budding-off" of the GOLGI apparatus. The GOLGI apparatus in PURKINJE cells can be classified into 4 categories including a perinuclear strand form (Type III), but most of them show randomly distributed granules and vesicles. Lightly stained networks are observable in astrocytes and oligodendrocytes. They do not show polarity in astrocytes whereas they have extensions in a few oligodendrocytes. BERGMANN glia may undergo cyclic changes indicating more advance differentiation than astrocytes and oligodendrocytes. Cerebellar glomerula show lightly stained networks with many fine granules. Granule cells, stellate cells, and basket cells are all poorly equipped equally with the EMBDEN-MEYERHOF (EM) pathway and with the hexosemonophosphate (HMP) shunt. GOLGI type II cells are richly equipped almost equally with both the EM pathway and the HMP shunt. All these neurons probably derive energy mainly from glucose in the circulating blood. PURKINJE cells may belong to the category of "usual neurons", because they are moderately equipped both with the EM pathway and the HMP shunt. However, they may derive their energy from the BERGMANN glia which have intense hexokinase activity but weak succinate dehydrogenase activity. The BERGMANN glia are more richly equipped with the HMP shunt than with the EM pathway and are rich in lactate dehydrogenase suggesting an "exceptional metabolic pattern". These glia may have active synthesizing ability. Astrocytes and oligodendrocytes are equipped with all the enzymes tested, and they show a tendency to surround the glomeruli. It is suggested that the glomerula may be surrounded by the glial sheaths with strong hexokinase activity, and that they may contain alpha-glucan phosphorylase, glucose-6-phosphate dehydrogenase, and glycerol-3-phosphate dehydrogenase in addition to the succinate dehydrogenase already reported. A few PURKINJE cells showed perinuclear concentrations of the reaction product only of succinate dehydrogenase at the sites of contacts between nucleoli and nuclear membranes. It is suggested that the nucleolus may receive adenosine at the sites of contacts between nucleoli and nuclear membranes...     

Histochemical studies on the morphology of the Golgi apparatus and its relation to catecholamine biosynthesis in the locus coeruleus of Rhesus and crab-eating monkeys.

Detailed histochemical studies have been conducted on the distribution of thiamine pyrophosphatase (TPPase), L-gulonolactone oxidase (GLO), and NAD-linked xylitol dehydrogenase (XDH) in every component of the Locus coeruleus (LC) of healthy adult male Rhesus and crab-eating monkeys in order to clearify the morphology of the Golgi apparatus (GA) and its relation to biosynthesis of catechol-amines in this special nucleus of the primate (NA nucleus A 6 as defined in the Rhesus monkey by German and Bowden [1975]). Medium-sized neurons of both species of monkeys, which are considered to play an important role in the LC, were classified into 5 groups on the basis of morphological patterns of the GA. Many neurons of both species of monkeys were positive for the XDH test while some neurons of the crab-eating monkey as well as a few neurons of the Rhesus monkey were positive for the GLO reaction. The LC of both species of monkeys must be composed of metabolically one kind of identical medium-sized parasympathetic neurons whose GA may continously undergo 5 distinct phasic changes depending on the functional state of that cell. However, the GA changes its shape much more significantly even within each group of the 5 in the crab-eating monkey than in the Rhesus monkey. The GA Type IV may correspond to the catabolic phase of the GA during which biosynthesis of both catecholamines and vitamin C should be going on. Production of vitamin C may greatly help biosynthesis of catecholamines in LC. The difference in species is evident between the 2 kinds of monkeys studied in regard to the degree of their ability to synthesize these substances. The degree of the ability to synthesize vitamin C parallels the density distribution of Type IV neurons in LC whose GA often develops much more greatly in the crab-eating monkey than in the Rhesus monkey.     

Histochemical studies on the relationship between the morphology of the Golgi apparatus and G6PD activity in the locus coeruleus and dorsal vagal nucleus of the rat (application of karyometry)

Histochemical studies on the distribution of TPPase and G6PD in the neurons of locus coeruleus (LC) and dorsal vagal nucleus (DVN) of rats have been conducted by using the TPPase method, the G6PD method, karyometry, and statistics under normal conditions. 1. Neurons of the LC and DVN may undergo phasic changes of the GOLGI apparatus (GA) under normal condition. 2. No significant difference was found between neurons of the LC and DVN in regard to the GA morphology, but in general the latter revealed more complicated and developed GA than in the former. 3. Surprisingly, the G6PD activity of LC neurons was very weak. This is in agreement with the previous report by IIJIMA and IMAI (1975), and in disagreement with FRIEDE (1966). 4. An intimate parallel relationship was found between the GA morphology and G6PD activity in the DVN. The findings support the vigorous synthesizing activity found in the previous study of the rat supraoptic nucleus (IIJIMA 1979). In contrast to the DVN, such a parallel relationship between the Ga shape and G6PD activity was absent in the LC. Both findings strongly suggest that the role of the GA may be functionally different in the LC and DVN.     

Histochemical studies on the distribution of hexokinase and several enzymes related to catecholamine production in the locus coeruleus of the squirrel monkey.

Protein sulfhydryl groups are histochemically demonstrated by reacting with DDD followed by coupling with Fast blue B. The molar absorptivity of the formed azo dye is 19000 per mole SH reacted. DDD simultaneously reacts with protein-SH- and -SS-groups. However, the reaction with SH-groups is approximately 1000 times faster than that observed with SS-groups. With Ehrlich ascites tumour cells the reaction of DDD with SH-groups is completed within 7 h while the reaction of DDD with SS-groups needs 14 days for completion. Due to the extreme difference in the reaction rates protein bound SH-groups as well as reactive SS-groups can be estimated quantitatively by cytospectrophotometrical methods. The cells investigated showed an average SH-content of (1,30 +/- 0,03) X 10(-14) M SH/cell while the average content of reactive SS-groups was (1,59 +/- 0,28) X 10(-14) M SS/cell. In addition it was found that especially the amount of reactive SS-groups per cell is not constant but exhibits seasonal variations.