Masao Mato

Study on distribution of pericyte and fluorescent granular perithelial (FGP) cell in the transitional region between arteriole and capillary in rat cerebral cortex.

The FGP (fluorescent granular perithelial) cell nominated by M. Mato were distributed around small cerebral vessels and potent in the uptake capacity. They are provided with surface antigens related to macrophage lineage. The aim of this report is to show the regional distribution of pericytes and novel perivascular cells (FGP cell) in relation to the glia limitans and basal lamina.

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.

Behavior of fluorescent granular perithelium (FGP) in cerebral cortex of SHR-SP rats under some conditions

The fluorescent granular perithelial cells (FGP) in control and experimental specimens of SHR-SP rats were studied with light and electron microscopes. The results obtained are as follows. The FGP in SHR-SP rats are localized along small cerebral vessels and provided with many irregularly shaped inclusion bodies. Their matrices are homogenous and relatively less dense. Sometimes, the FGP fall into degeneration and their cytoplasm shrinks and fills with small dense granules. Concomitantly, collagen fibers appear surrounding them. After feeding rats a fat-rich chow, lipoidal substances appear in intracellular granules of FGP at the light microscopical level. Electron microscopically, the FGP are swollen and their inclusion bodies vary in shape and content. Large inclusion bodies are composed of several middle-sized inclusion bodies with heterogenous matrices. Frequently, pale inclusion bodies are provided with intensely stained limiting membranes. These facts suggest an incorporation of fat into the FGP. With the administration of elastase, intracellular lipid decreases moderately and the FGP scarcely swell. The cytoplasm of FGP and the contents of inclusion bodies become defined and contrasty. From this evidence, elastase seems to facilitate a fat metabolism in FGP. Morphological and functional differences between FGP and other perivascular cells including pericytes, microglia, and mast cells are briefly discussed.

Unusual intracytoplasmic lamellar bodies in a malignant gonadal stromal tumor

SummaryCharacteristic intracytoplasmic lamellar bodies were found in a malignant gonadal stromal tumor. These bodies consisted of the stacks of up to 200 tubular cisternae arranged in parallel. Each cisterna had a circular section in tangential view and a diameter of about 85 nm. The cisternae on the outermost side of these lamellar bodies tended to be dilated and adorned with ribosomes. The ends of cisternae were often contiguous with rough-surfaced endoplasmic reticulum. The latter feature is also seen in annulate lamellae, but periodically spaced annuli or discontinuities characteristic of annulate lamellae were never observed. Furthermore, fine ribosomal granules resembling a rosary were recognizable along the whole circumference of the outer surface of each cisterna.The unique structure we describe is a cytoplasmic organelle which, like annulate lamellae, is closely associated with the endoplasmic reticulum and is presumed to be related to the genesis of rough-surfaced endoplasmic reticulum in tumor cells.

Inclusions in novel perivascular macrophages (Mato's fluorescent granular perithelial cells) and neurons in the cerebral cortex of Hex A- and Hex B-deficient mice

Abstract. Beta-hexosaminidases are important enzymes for lipid and saccharide metabolism in the brain. In mice deficient in these enzymes, indigestible metabolic intermediates deposit in neurons. Inclusions such as membranous cytoplasmic bodies (MCB) and zebra bodies were seen in neurons of Tay-Sachs (TS) model mice, Sandhoffs disease (SD) model mice, and double knockout (DKO) mice. However, the cerebral perivascular macrophages discovered by Mato are active in the uptake of waste products and regarded as scavenger cells under steady-state conditions. We observed that indigestible components derived from neurons were taken up by the perivascular macrophages of TS mice by pinocytosis, but those of SD and DKO mice contained only pale inclusions and had marked vacuolations, and pinocytosis was rarely observed. Histochemically, the inclusions in the perivascular macrophages of TS mice were positive for the PAS stain, but those of SD and DKO mice were negative. In addition, the perivascular cells of TS mice expressed clear positive immunoreactivity against BM-8 and F4/80, but those of DKO mice had very weak BM-8 and F4/80 immunoreactivity. These differences between TS, SD, and DKO mice are based on their metabolism of oligosaccharides and glycosaminoglycans (GAG). Thus, hexosaminidase B is more important for keeping normal morphology and function of perivascular macrophages than hexosaminidase A. The foamy cells that appeared along the cerebral microvessels in lipidosis and saccharidosis were identified as perivascular macrophages (Matos fluorescent granular perithelial cells: FGP cells).

Radioautographic study on the obliteration of the ductus arteriosus botalli

Durch autoradiographische Untersuchungen wurde gezeigt, daß die Obliteration des Ductus arteriosus Botalli, welche während einer kritischen Zeit abläuft, nicht nur durch die Wandzellen des Ductus sondern auch Elemente des strömenden Blutes getragen wird. Während der Phase der Proliferation besteht eine besondere Störanfälligkeit der Zellen, insbesondere gegenüber Sauerstoffmangel. Es scheint, daß die Suszeptibilität genisch verankert ist. From the findings obtained from the radioautographic study on the obliteration of the ductus arteriosus, the authors confirmed that the obliteration was not caused only by the proliferation of the cells in the intimal layer of the ductus, but rather by the migration of the cells into the lumen. When the embryos reached the final stage of fetal life, their ductus arteriosus possessed a specific property to obliterate after the blood flow ceased. Some discussions are devoted to the etiology of the patent ductus arteriosus.

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.

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.

In vitro characterization of Mato's FGP cells isolated from rat cerebrum

Matos FGP cells surrounding cerebral arterioles play a significant role in the maintenance of a homeostatic microenvironment in the brain. In this study, the perivascular cells were isolated from rat cerebral microvessels and cultured in vitro to characterize their phenotype. Autofluorescence of the intracellular granules in cultured cells and the uptake of HRP and DiI-Ac-LDL by these cells were observed. The cells reacted positively to an anti-scavenger receptor A antibody. Positive immunoreactions of cultured cells to ED1 and ED2 antibodies were observed, whereas they were weak or negative to ED3 and OX42 antibodies. Acid phosphatase activity was detected in the granules of cultured cells. In conclusion, the cells cultivated under the present conditions revealed very similar characteristics to Matos FGP cells in situ and therefore are useful for studies on FGP cells.

Studies on the obliteration of the ductus arteriosus in rat embryos

SummaryWistar rat embryos weighing over 3 g obtained by Caesarean section can adapt to extrauterine life. The ductus arteriosus of such embryos is obliterated within 2 hours after the first breath. However, the d.a. of embryos weighing 3 to 4 g does not obliterate continuously but distends again after about 40 to 60 minutes.The finding is in accordance with the inconstancy of the blood circulation through the vessels in the critical period stated by Doerr. The “inconstancy” of the closing process is characteristic in the ductus arteriosus of premature embryos. Further, it is shown in this study that the degeneration of intimal cells, disruption of elastic lamellae and protrusion of the intimal tissue are essential for the complete obliteration of the ductus arteriosus. In addition, the tonus of the outer circular muscle layers is increased. The degenerative changes in the vascular wall are observed at first in the subendothelial cells, and these cells seem to play a principal role in the modification of the architecture of the d.a. The transformation of smooth-muscle cells and the change of cytoplasmic organelles were characteristic depending on the period after the first breath.The other factors concerning the obliteration of the d.a. are discussed.