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M Mato

Publications and source records attributed to M Mato.

At least 55 records · Page 3Linked to original sources
PubMed1982

[Studies on cerebral scavenger cells (fluorescent granular perithelial cells) - especially uptake and digestion of incorporated fat].

Small cerebral vessels including capillaries are provided with the specific barrier (blood brain barrier) for a transport of substances from blood to cerebral tissue. However, it is also established that fat soluble substances are easily permeable in this barrier. Along cerebral small vessels, the cells having intracellular fluorescent granules are distributed and named "fluorescent granular perithelia (F.G.P.)" by the authors. They are potent in the uptake capacity for exogenous substances as reported in the previous papers. In this study, 24 male Wistar rats aged 8 months and 2.5 years old were employed. They were fed with a fat rich chow (Oriental Co.) containing 10% lard, 2% cholesterol and methylthiouracil for one day and fifteen days. Half of them was subcutaneously injected with 5 mg/kg of elastase (Eisai Co.) dissolved in physiological saline once a day. To clarify the effect of elastase on fat incorporated by F.G.P., 4 rats aged 2.5 years were fed with a fat rich chow for 2 days. After then, they were fed with ordinal rat chow for 3 days with or without elastase injection. After decapitation, cerebral cortex of rats was removed in cold physiological saline and sliced with a blade. Half of the sliced specimens was prepared by the authors' method (Mato and Ookawara, 1979) and stained with hematoxylin eosin, periodic acid Schiff reaction and sudan black B for a light microscopical observation. The other half of the specimens was immersed in a mixture containing 2% paraformaldehyde and 2.5% glutaraldehyde buffered with 0.1M phosphate solution (pH 7.4) for 10 h. The specimens were then postfixed with osmium tetroxide buffered with the same solution for 2h. The other procedures for embedding and cutting were the same as in a routine method. Following findings were obtained at the light and electron microscopical levels; when they were fed with a fat rich chow, fat in blood passed through vascular walls and was taken up by F.G.P.. The quantity of fatty deposits in F.G.P. was different depending on age of rats employed for the experiment. The deposits in F.G.P. increased with advancing of age. That is, in old rats a lot of deposits were chiefly distributed in inclusion bodies at one and fifteen days after the administration. The difference in quantity of deposits between young and old rats was not only based on the permeability of vessels, but on the digestion capacity of F.G.P. for fat. On the other hand, Elastase, a specific enzyme for lysis and synthesis of elastic components, prepared by Eisai Co., made a suppressive effect to the permeability of cerebral small vessels and facilitated markedly the digestion capacity of F.G.P. for fat, although the mechanism remained unsettled. From this standpoint, F.G.P. are also designated as "cerebral scavenger cells".

Animals↗
PubMed1981

Influences of age and vasopressin on the uptake capacity of fluorescent granular perithelial cells (FGP) of small cerebral vessels of the rat.

Fluorescent granular perithelial cells (FGP) were found in the perivascular space around fine cerebral blood vessels. Their profiles and intracellular inclusions varied with the age of the animals. The FGP are able to take up exogenous substances administered intraventricularly. With light and electron microscopy, the relation between the uptake capacity of FGP and the aging of animals was studied using horseradish peroxidase (HRP). The effects of vasopressin on the uptake of HRP also were examined. The results can be summarized as follows: 1) The uptake capacity of FGP diminished with aging, that is, the reaction product of administered HRP was found abundantly in FGP in young rats, while it was sparse in the FGP of old rats and 2) vasopressin increased the incorporation of HRP into the FGP of both young and old rats. The possible role of vasopressin in modulating the uptake capacity of FGP is considered, and the difference between FGP and other perivascular cells are discussed.

Aging↗
PubMed1981

Studies on fluorescent granular perithelium (F.G.P.) of rat cerebral cortex - especially referring to morphological changes in aging.

In this paper, the granule laden cells localizing around fine vessels in cerebral cortex were investigated with fluorescent, light and electron microscopes using Wistar rats. These cells were designated as fluorescent granular perithelial cells (F.G.P.). The findings obtained in this study were summarized as follows; 1. The F.G.P. were one of essential components of cerebral vessels and separated clearly from nervous tissue by a basal lamina. They were often observed at bifurcating regions of fine vessels. 2. The F.G.P. seemed to differentiate morphologically around birth, and the specific granules to them began to emit yellow fluorescence at second week and attained to a definite level of fluorescence intensity at eighth week. Microfluorometrically, the peak of emission stood at 530 micrometer. Accompanying with a growth of animals, eosinophilia of granules became strong. Sudanophilic areas in the F.G.P. were limited to a periphery of granules. Anisogranularity was evident in old rats age second and third year. 3. Electronmicroscopically, the specific cytoplasmic organelles in the F.G.P. were round electron opaque bodies and vesico-tubular system or sac shaped smooth surfaced endoplasmic reticula. The electron opaque bodies appeared clearly at second week after birth, and changed their profiles and contents with aging of rats. In old rats, they looked porous and honeycomb like structure, and sometimes, whole cytoplasm of the F.G.P. was occupied with these structures. Some sac shaped endoplasmic reticula contained less intense material in one side and seemed to be associated with a formation of electron opaque bodies. Further, it was very interesting that the extensions of some F.G.P. encircled completely the entire circumferences of cerebral vessels. It looked as if fine vessels would penetrate into the F.G.P. 4. After administration of major tranquilizers and prednisolone, fluorescence and eosinophilia of intracellular granules decreased moderately, and the other drugs, - vitamins E and B - enhanced the both. 5HT and 5HTP enhanced the fluorescence, but suppressed the eosinophilia. From the findings mentioned above, the F.G.P. were expected to play an important role in a transport of nourish substance from fine vessels to neurons, and in a removal of some products in the extracellular spaces of central nervous system.

5-Hydroxytryptophan↗
PubMed1980

Regression of granular pericytes in cerebral fine vessels of rats after administration of vitamin E deficient diet.

Prolonged administration of a vitamin E deficient diet to Wistar rats resulted in regressive changes in granular pericytes distributed around fine vessels of the cerebral cortex. The regressive signs included expansion of endoplasmic reticula, sweling of mitochondria and increase of vesicular structures. Rupture of the limiting membranes of the intracellular granules often accompanied these changes. The finding seems important for an understanding of the physiology and nutriology of granular pericytes in the brain.

Animals↗
PubMed1980

Uptake of exogenous substances and marked infoldings of the fluorescent granular pericyte in cerebral fine vessels.

Exogenous substances such as trypan blue and horseradish peroxidase administered intraventricularly are taken up by granular pericytes in cerebral fine vessels. These cells are provided with elongated and complicated infoldings. Pinocytotic vesicles occur often along the infoldings, and ends of infoldings are swollen and assume vesicular shapes. The specific morphology of the granular perithelial cells is considered to favor a removal of metabolic wates in cerebral tissue.

Animals↗
PubMed1979

A simple method for observation of capillary nets in rat brain cortex.

By the authors' technic, the profiles of capillaries in rat brain cortex were clearly demonstrated. The capillaries formed complicated nets by sprouting of their finer branches and anastomosing with each other. Further, a kind of perivascular cells with yellow autofluorescent granules was distributed close to capillaries, arterioles or venules. The seemed to be a special form of macrophage in the brain cortex.

Animals↗
PubMed1978

Histochemical and chronobiological studies on uptake of L-DOPA by granulocytes--its promotion and suppression.

The uptake capacity of granulocytes for L-DOPA was investigated from the aspect of histochemistry and chronobiology. For a histochemical research, modified FALCK-HILLARP method for catecholamine, CORRODI's test for identification of L-DOPA and an electron microscopical survey of glycogen particles were carried out. For a chronobiological research, daily and seasonal changes in the uptake of L-DOPA by granulocytes were examined with blood smear method of the authors. From this experiment, following points became clear; 1. The uptake capacity of granulocytes for L-DOPA varies with a clock-time and a season judging from fluorescent intensity and tincture of granulocytes. 2. The uptake capacity of granulocytes for L-DOPA was suppressed by major tranquilizers especially haloperidol, and by lithium carbonate, while the uptake was enhanced by prednisolone, dexamethasone, MK-486, and dibutyryl cyclic AMP. 3. The electron opacity of glycogen particles in granulocytes weakened significantly after the administration of L-DOPA. Isoproterenol had also a similar effect, but the effect of the former was superior to that of the latter under the authors' conditions. Haloperidol inhibited strongly the decrease of glycogen caused by L-DOPA. 4. DOPAmine was hardly uptaken by granulocytes in general. Glycogen in granulocytes did not show a marked decrease after the administration of DOPAmine. 5. From the evidence mentioned above, glycogen content in granulocytes was assumed to be closely associated with the uptake of monoamine by granulocytes.

Animals↗
PubMed1976

Fluctuation of fluorescent material in the rat's and human leucocytes under various situation.

When modified FALCK-HILLARP technic was applied to blood smears of rat and human specimens, the fluorescence was detected not only in platelets, but in leucocytes. In rat leucocytes and platelets, the bimodal daily rhythm of fluorescent material is observed under physiological condition. The rhythm is modified considerably if animals are exposed to the continuous lighting. The intensity and number of the fluorescent cells in the human smears increased markedly in patients suffering from schizophrenia compared with controls. The content of fluorescent material in leucocytes assumes to be closely related with an activity of the living states.

Adult↗
PubMed1976

The effects of L-DOPA, serotonin, reserpine and chlorpromazine on the daily rhythm of fluorescent intensity in leucocytes and blood platelets.

1) The rhythmic fluctuation of fluorescent intensity of leucocytes and platelets of rats was modified by the administration of some drugs such as L- DOPA, serotonin, reserpine and chlorpromazine. Timing of administration was determined to get clearcut results. The different results were expected by the administration of drugs at the other time of day. 2) The administration of L-DOPA enhanced the fluorescent intensity of leucocytes and platelets, and the tincture of them tended strongly to be green at 4 to 10 h after the treatment. The administration of serotonin suppressed the fluorescent intensity of leucocytes temporarily, but inversely enhanced the intensity of platelets significantly. Reserpine and chlorpromazine had a similar suppressive effect on the fluorescent intensity of leucocytes and platelets within 30 h after the treatment. Compared with them, the influence of reserpine was stronger than that of chlorpromazine. 3) In fact, these drugs made an marked influence on the rhythmic fluctuation of fluorescence intensity in leucocytes and platelets, but the physiological rhythmicity was remained in the ground of modified fluctuation of rats which were treated by those drugs.

Animals↗
PubMed1975

Ultrastructures of glosso-palatal fusion after treatment of meclozine-hydrochloride.

The behavior of the epithelial cells on the tongue and palatal processes during glosso-palatal fusion induced by Meclozine-hydrochloride was investigated with light and electron microscopes. Microscopical observations revealed that; at two or three days after the administration, the palatal processes were approximating to the tongue, and the superficial cells on the lateral sides of tongue became swollen and to have inclusion bodies, and in the epithelium on the medial sides of palatal processes, some inclusion bodies appeared too. At the time of contact, the superficial epithelial cells of tongue tended to degenerate markedly, and these degenerating cells were dissociated from the epithelium, and concurrently, superficial layer of the palatal epithelium became to have a lot of inclusion bodies. Between the two tissues, attachment devices developed just after the contact, and then, the cells in the intervening epithelial lining fell into a degeneration gradually. As well known, Meclozine-hydrochloride is one of important miner tranquilizers. From the findings mentioned above, it seemed to be possible that a heterotopic fusion caused with this drug is a result of a destruction of embryonic epithelium on tongue and palatal processes at a certain stage of development.

Animals↗
PubMed1975

Ultrastructural changes in rat palatal epithelium after beta-aminopropionitrile.

Beta-Aminopropionitrile (BAPN) retarded or suppressed epithelial changes in the medial edge of the palatal process in later stages of gestation in rats. Programmed cell death did not follow the usual pattern, and only a few lysosomes were observed on day 18 of gestation. The sensitivity of the medial epithelium to BAPN appeared to be different in various areas of the palatal epithelium; the epithelium on the anterior region of the palatal process was hypertrophied and keratinized, while posteriorly the medial or neighboring epithelium was very thin and, in neonatal rats, the covering was absent. A basal lamina was distinct in the anterior region and indistinct or fragmented posteriorly. Collagen fibers did not develop adjacent to the basal lamina, and an amorphous material was scattered throughout the mesenchymal tissue. These findings suggest that BAPN decreases the "connecting capacity" between mesenchyme and epithelium, and results in a modification of epithelial changes.

Aminopropionitrile↗