There is a sex difference in the cytosol androgen receptor from the rat and mouse submandibular glands, it being higher in females than in males even though the circulating androgen level is predominantly higher in males. To understand this phenomenon, the characteristics of the cytosol and nuclear androgen receptor of both sexes and its translocation to the nuclei have been investigated and the findings, obtained mainly in our laboratory are reviewed. The exchange assay using mersalyl and monothioglycerol revealed that the cytosol receptor is mostly unoccupied in both sexes. Dialysis, gel filtration and ATP induced transformation of the cytosol androgen receptor as did heat and salt treatments, although each transformed receptor displayed a different molecular weight.
The sex difference in the subcellular distribution of the androgen receptor was observed in mice; the receptor exists mainly in nuclei in the occupied form in males, whereas it occurs mostly in cytosol in the unoccupied form in females.

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The present study was attempted to elucidate the histochemical characteristics of degenera. tion, destruction and regeneration of skeletal muscles following cryotreatment. Soleus (red and slow muscle), gastrocnemius (white and fast muscle) and masseter muscles (intermediate muscle) in rats were employed. The skeletal muscle fibers were classified as the I type, HA type, II B type and HC type according to the Brooke and Kaiser's procedure with myosin ATPase activities with acid and alkaline pre-incubation. Degeneration and destruction processes of all types of skeletal muscles after cryotreatment were similar to each other. Numerous satellite cells (mononuclear cells) existed in the muscle fibers undergoing destruction one to three days after cryotreatment. Regenerating muscle fibers developed from them five to seven days later.
The internal components of the muscle fiber had positive lectin stainabilities during the fiber destruction stages and during the early stage of muscle fiber regeneration. Mitochondrial enzymes were present in the regenerating muscle fibers five days after cryotreatment. In the regeneration of muscle fibers, all the fibers were of the H C type and then transformation of the muscle fibers occur from the H C type to the I and the II B types. After that, the H B type was transformend to the II Atype.

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As revealed by electron microscopy, we observed two types of blood capillaries in the rat incisor peripheral pulp. One was a continuous capillary wall and the other was a fenestrated capillary wall. The former were found chiefly in the basal portion of the incisor and the latter were only in the incisal portion. The continuous capillary may change its configuration into the fenestrated capillary type at the middle portion of the incisor where the odontoblasts are young and the mineralization of dentin progresses remarkably. When the configurational change occured a thick endothelial swelling appeared in the capillary lumen. It seems that this distribution of capillaries is related to their function, i.e., the mineralization of dentin. In this study, we prepared the pulp materials for microscopy without decalcification by stripping off the hard tissues (enamel and dentin) from the pulp using fine tweezers. Using this technique, good results were obtained.

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Rats anesthetized at different ages (2 days to over 60 days ; adult) were tested for the masseter muscle excitatory reflex (jaw closing reflex) elicited by mechanical stimulation of the upper jaw area.
In the 2-day-old rat, the reflex was evoked by pressure stimuli of the incisor gingiva, eruption site of the incisors, palate, upper lip and snout.
With increasing age, the reflex activity decreased from all side except the eruption site of the incisors. With increasing maturity the field of the upper jaw from which the masseter muscle excitatory reflex was evoked thus became narrower eventually to localize around the incisors. After 21 days, the reflex activity almost disappeared.
At the eruption site of the incisors, the reflex excitation was well elicited until their eruption.
After 13 days, by linguolabial pressure to the upper incisor, the reflex activity was well evoked, and with increasing age the reflex activity increased gradually. However after 11 days labiolingual pressure elicited a poor reflex response, and in the adult rat it had almost disappeared.
This study revealed that (1) in the young rat, the jaw closing reflex was elicited from a wide field in the upper jaw area, (2) with increasing maturity, the field became narrower to finally localize around the incisors, (3) in the mature rat, the reflex was evoked mainly by pressure on the incisors in the linguolabial direction.

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Bacteroides melaninogenicus group, a common bacteria in the child's oral cavity, was frequently isolated from the infected root canals of the deciduous teeth. Then, we studied the presence or absence of the Bacteroides within the radicular granuloma caused by the apical periodontitis of deciduous teeth.
The granulomas formed at the bifurcation of the roots of the three deciduous teeth were examined with histopathological and fluorescent antibody (Fluoretec-M, Pfizer, Inc., U.S.A) staining methods.
Histologically, the granulomas consisted of stratififed squamous epithelium and inflammatory cell infiltration, proliferation of capillaries and fibrous tissue in the subepithelial layer. Also, neutrophiles and mast cells were shown in the same area. Although bacteria could not be observed by gram staining of paraffin-embedded sections, rod-like bacteria were found in the tissue of subepithelial connective tissue by the fluorescent antibody staining method. It is suggested that Bacteroides melaninogenicus group were present in the radicular granulomas of the deciduous teeth.

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The spatial distribution of motor endplates in rat masseter muscle was investigated histochemically by staining for acetylcholinesterase (Ach E) activity in serial frozen sections cut in coronal, horizontal and parasagittal planes. Motor endplates were found to be scattered in several regions of this muscle. These regions were identical with the muscular compartments in this muscle previously reported by us (Matsumoto, H.& Katsura, S: Multiple compartmentalization in the fiber architecture of rat masseter muscle. Acta Anat. Nippon. 60: 90-98, 1985). Several motor endplates were found in each region. All motor endplates were of the ' terminaisons en plaque' type. One motor endplate for each muscle fiber was situated in approximately the central one-third of the fiber and one motor nerve ending was found in each motor endplate.

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In order to clarify the mechanisms whereby dentin resorption takes place during the shedding of deciduous teeth, human deciduous teeth were examined by means of light microscopy (LM), scanning (SEM) and transmission (TEM) electron microscopy. Resorption lacunae were found in the dentin surfaces facing both the periodontal ligament and the pulp. In these resorptive dentin surfaces not only multinucleated odontoclasts but also mononuclear fibroblast-like cells were localized. Correlated observations using LM and SEM made it clear that in the deep resorption lacunae, which are occupied by odontclasts, prominent dissolution of peritubular matrix had occurred, while the shallow resorption lacunae did not show peritubular matrix dissolution In thin sections, odontoclasts showed such cytological features as have been described in previous reports. The cytoplasm of the mononuclear cells contained many mitochondria, rough-surfaced endopiasmic reticulum, well-developed Golgi apparatus and lysosomal bodies but no secretion granules. These mononuclear cells appeared not only in sites adjacent to odontoclasts but also within the ruffled border zone of odontoclast. The mononuclear cell sometimes contained endocytotic vacuoles containing collagen fibrils, and deep membrane invaginations enclosing collagen fibrils in their cell surfaces facing the resorptive dentin matrix.

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In order to investigate histopathologically the dentinal and pulpal response to carious lesion, Sprague-Dawley rats were fed with a cariogenic diet which contained 60% sucrose, for a period ranging from five to sixteen weeks. Paraffin sections were made after the animals were killed at the appropriate intervals and specimens were decalcified with 5% EDTA solution. The sections were stained with H. E., PAS, Azan and Gram staining and observed by light microscopy.
The results obtained were as follows: With respect to caries of dentin, the lesion was recognized as having reached the dentine at the fifth week. At the eighth week, the lesion was established in the dentine, and at the eleventh week, pulpal exposure was noted in almost all cases. Generally, onset of lesion was found at the pit and fissure regions, but the initiation of the lesion was also noted at the enamel free area in some cases. The carious lesion of the dentin such as the infected dentinal tubules, liquefaction foci and clefts were a similar to those found in human dentine. Formation of secondary dentin due to carious invasion was markedly apparent in rat. Regardless of the prominent existence of carious lesion of dentin, in almost all cases, the pulpal tissue showed a less severe response in comparison to the human pulp. However, a marked inflammatory cell infiltration and abscess formation were seldom seen. In cases of exposure, the pulp tissue showed gangrenous changes and numerous Gram positive microorganisms including cocci and bacilli were found. As compared to human carious lesion of dentin, the fibrotic changes in the pulp tissue of the rat resulting from the carious invasion were greater in degree than similar changes in the human pulp.
It was concluded that carious lesions of dentin obtained from cariogenic diet fed rat molars were characterized by an onset of the carious lesion at the enamel-free area, a marked secondary dentin formation, and fibrotic changes. A definite relation betw een the severity of the carious lesion of dentin and pulpal lesions could not be found. Bacterial colonies were frequently seen in the exposed pulp tissue.

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In order to investigative the localization of PG in gingival tissue by the direct immuno-fluorescein antibody technique, a fundamental study was undertaken both on the preparation of the antigen and on the separation, specificity, staining of the antibody.
1) The quantity of PG used to bind PG to carrier-protein in this experiment was as little as half the amount of PG which had so far been used. Molar ratio of PG-protein products was approxi-mately 10 moles of PG per one mole of carrier-protein.
2) 10ml antiserum was purified by an affinity column chromatography coupling of PGE to AHSepharose. As the result, 8mg PG-specific antibody was obtained. 3) The cross-reactivity of the antibody described above 16 per cent against PGF₂α, 13 per cent against PGB₂, and less than 5 per cent against A₁, A₂, E₁, F₁α, respectively.
4) Even 0.2 per cent protein solution was able to be labelled with fluorescein isothiocyanate (FITC).
5) It seemed, that the PG staining in rat uterus, as well as the specificity of the antibody examined by the present author was better than those obtained by Van Orden.
6) PG was localized in cytoplasms like the macrophage observed beneath the gingival crest and the oral gingival epithelia in periodontal disease. But PG was not localized in the area in which many lymphocytes were observed to infiltrate beneath the oral epithelium.

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The hydrophobicity of cell-surface of Streptococcus mutans was studied using 11 laboratory strains of S. mutans and 6 strains of the mutant of S. mutans Kl-R. The hydrophobicity was measured by the adsorption of the microorganisms to hexadecane, and expressed as percent reduction from the initial optical density of the cell suspension. The hydrophobicity of laboratory strains of S. mutans varied from 45.9% to 98.0% in 0.01M potassium phosphate buffer (KPB), pH 7.2 and from 63.8% to 96.9% in PUM buffer (Rosenberg, et al., 1980). S. mutans AHT, 6715 and MT3940 showed higher values of the hydrophobicity in PUM buffer than in KPB. Mutants showed 64.9 to 100.7 percent of hydrophobicity of the parent in KPB. The hydrophobicities of the mutants as well as parent varied slightly between KPB and PUM buffer. The effect of cell density and pH on the hydrophobicity of S. mutans OMZ 176 (middle hydrophobic strain) was greater than that of S. mutans HS-6 (high hydrophobic strain). Furthermore washed cells of S. mutans HS-6, OMZ176, K1-R and mutant M38 were treated with subtilisin, trypsin, pepsin, dextranase, 5M of urea or heating at 100°C in order to study the change in hydrophobicity. Proteolytic enzymes produced decreasing hydrophobicity of all strains.
The results of this experiment suggest that the hydrophobicity of cell-surface varies with strains of S. mutans and that the proteinic substance of the cell-surface is related to hydrophobicity.

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Phenolic compounds are widely used in the treatment of inflammtory conditions of the dental pulp. Despite the extensive use of these drugs in dental clinics, studies on the mode of their action on the inflammatory response have been infrequent. Recently, it has been shown that some scavengers for oxygen free radicals are effective in inflammatory conditions. Phenolic compounds are known to possess a property of scavenger for oxygen free radicals. So, the mode of action of the phenolic compounds on the inflammatory response was examined in this study to define the anti-inflammatory mechanism of phenolic compounds as a scavenger for oxygen free radicals. Chemotactic activity of guinea pig peritoneal neutrophils and macrophages to N-formyl-methionyl-leucyl-phenylalanine (FMLP) were suppressed in a dose dependent manner by phenolic compounds. The relative order of inhibitory activity of phenolic compounds was as follows: eugenol>>thymol>guaiacol≥p-cresol≥o-cresol>m-cresol>>phenol. Phenol inhibited the leukocyte migration to FMLP at the concentration of 2 to 5 mM and this concentration was about one fiftieth to one twentieth of the concentration of phenol which brings about protein denaturation. The inhibitory effect of phenol on leukocyte chemotaxis was reversed by washing the cells before incubation with FMLP. A free phenolic hydroxyl group is essential for scavenging oxygen free radicals. Blocking the hydroxyl group by conversion to an ether markedly diminished antichemotactic activity, as is demonstrated by comparing guaiacol with veratrole, or eugenol with safrole. There was a consistent positive relationship between ID₅₀ of PGE₂ synthesis and the inhibitory dose of leukocyte chemotaxis in phenolic compounds. These findings suggest that inhibition of prostaglandin synthesis was involved in the anti-inflammatory mechanism of phenolic compounds and the prevention of the production of oxygen free radicals by the leukocyte appears to be one of the anti-inflammatory actions of phenolic compounds.

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Effects of oxygen on the growth of oral indigenous aerotolerant anaerobes, Streptococci and Lactobacilli, and some other aerobes and anaerobes were studied by means of stab-, shake-, and shaking culture. The bacterial growth in shaking culture using a liquid medium was measured by absorbancy following incubation in aerobic and anaerobic conditions. The ratio of growth in aerobic shaking culture to growth in anaerobic shaking culture of a given strain was taken as a quantitative measure for comparing different species and strains with the effect of oxygen on their growth. The relative bacterial growth ratio (abbreviated to RBGR) thus defined varied from co in obligate aerobes to 0 in obligate anaerobes, indicating a consistency with the usual qualitative observations using stab culture. RBGR in facultative anaerobes ranged from 6.0 to 1.8 and RBGR in aerotolerant anaerobes from 1.6 to 0.2. Growth inhibited zones were clearly observed below the medium surface for aerotolerant anaerobes and obligate anaerobes in shake culture using a semi-solid medium.

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Na⁺, K⁺-dependent ATPase is an intrinsic enzyme embeded in the plasma membranes. The function of the enzyme is to replace intracellular sodium ions with extracellular potassium ions using the free energy of ATP hydrolysis in animal cells. In this paper, the effect of dibucaine (D) on the enzyme was investigated. The p-NPPase and Na⁺, K⁺-ATPase activities of the enzyme were measured in various concentrations of D. The apparent affinities of the D-treated enzyme for ATP, Na⁺, Mg²⁺ and K⁺ were examined. Low concentrations of D inhibited the enzyme slightly, whereas higher concentrations inhibited the enzyme greatly. The apparent affinities of the enzyme for ATP, Mg²⁺ and K⁺ were changed by the treatment with high concentrations of D. The apparent affinity for K⁺ was only slightly changed by the treatment with low concentrations of D. The enzyme treated with high concentrations of D in the presence of K⁺ was shown to be slightly inhibited with the increase in the apparent affinity for ATP.
The results were as follows: D is bound to the enzyme and causes a decrease in the p-NPPase and Na⁺, K⁺-ATPase activities. At least two apparently different D-binding sites, high and low exist. K⁺ ihibites D-binding to low-affinity sites. The inhibitory effects of D is possibly due to interference with the interaction between the enzyme protein and the phospholipids.

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Five strains of gram negative, motile rods were isolated from foci of human periodontal disease. According to morphological, biological and biochemical characteristics, these isolates seemedto belong to the genus Selenomonas.
However, the ability to ferment carbohydates of these strains were different from those of S. sputigena described in the VPI manual and Bergey's manual.

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The distribution of interepithelial cells in the rat submandibular gland was investigated histologically and ultrastructurally. All the interepithelial cells were small lymphocytes with a smoothor shallow-indented nuclear outline, and were located below the level of the epithelial cell nuclei ofacini and ducts. No other cells such as Langerhans cells or cerebriform cells, such as are commonly found in stratified squamous epithelia, were detected. A mean of 6.7 interepithelial lymphocytes per1, 000 salivary gland epithelial cells was found: 7.1 in acini, 4.6 in intercalated ducts, 6.7 in gran: ular and striated ducts, and 8.3 in excretory ducts.

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The distribution of peptidergic (substance P and vasoactive intestinal polypeptide) nervefibres along the walls of blood vessels was examined in feline canine tooth pulps by an indirect immunofluorescence method.
Substance P (SP)-containing nerve fibres were observed in nerve bundles entering into the pulpalong the blood vessels. Only one or two nerve fibres showed SP immunofluorescence in a thick nervebundle. Around the blood vessels in the central pulp, many SP-positive nerve fibres with varicositieswere observed. They showed a network arrangement surrounding the walls of large bloodvessels. Near the odontoblastic layer, some of the small blood vessels were associated with single SPfibres. Not all blood vessels were accompanied by SP nervefibres and not all SP nerve fibres wererunning along the blood vessels.
Vasoactive intestinal polypeptide (VIP)-containing nerve fibres were also observed in apical nervebundles, but the number of VIP nerve fibres was fewer than that of SP nerve fibres. The distributionpattern of VIP nerve fibres surrounding the pulpal blood vessels was very similar to that of SPnerve fibres, but the number of VIP nerve fibres was also fewer than that of SP nerve fibres.

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Tissue mast cells (TMC) were counted in the human tongue of autopsy cases (M 69, F 46). The average number of TMC per unit field was 15.1±10.7 in the anterior, 7.7±4.2 in the middleand 4.8±3.2 in the posterior site, and there were significant differences between each of the sites.The average number of TMC in the three sites was significantly greater in the tongues of patientswho had died from malignant neoplasm of the breast, and the lowest number was from patients whohad died from malignant neoplasm of the blood. In the tongue of the patients with liver disease theaverage number of TMC was much greater in those of patients with liver cell carcinoma with cirrhosis, liver cell carcinoma and liver cirrhosis, than in the tongues of cases which had died due tochronic hepatitis and fulminant hepatitis where the average number was less. The authors considerthat these findings on TMC in the tongue have the merit of providing the foundation on which anexplanation of relationship between the histopathology of the tongue and the underlying general diseasemay be found.

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It was investigated that myeloperoxidase prepared from polymorphonuclear leukocytes detoxicates and inactivates the microbial metabolite antimycins A₁, A₂ and A₃ and several enzymessuch as trypsin, papain, chymopapain pepsin, collagenase, alkaline phosphatase and lysozymeand trypsin inhibitor in the presence of hydrogen peroxide and chloride ions. These reactions were pH dependent and the maxima were found with the pH at 5.0 to 6.0. In the absence of chlorideions, no detoxication and inactivation were observed. The detoxication and inactivation were alsoabrogated by omitting myeloperoxidase or hydrogen peroxide, or by heating of myeloperoxidase. The myeloperoxidase could be replaced by leukocytes.

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The morphological investigation of the sensory nerve endings in the oral mucosa has been carried out under two different processes. One was planned to clarify the construction of the nerve ending and the relationship between the axon terminal and the associated cells, the other to investigate the distribution of nerve endings involved in the tactile or pressure sensitivity. We had originally chosen the latter approach and, in the previous report, the distribution of the sensory nerve endings were mainly studied in the mouse labial mucosa. The present study was designed to examine the distribution of organized sensory nerve endings in the rat labial mucosa.

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Periodontal disorders are accompanied by a series of clinical symptoms such as formation of dental plaque, deposition of dental calculus, changes in the colour of gingiva, morbid abnormal formation of the gingival pocket, purulent discharge and mobility of teeth. Among these, bleeding from the perigingival area is a rather marked symptom. There are many outpatients who visit the department of dentistry with perigingival bleeding as the chief complaint. Thus, the problem of bleeding and hemostasis is, along with the inflammatory reactions, an important issue that is frequently encountered.
Fibrinolysis is a reaction involving a series of enzymes including plasmin. Plasmin exists in vivo as an inactive plasminogen and is activated by tissue activators, bacteriokinase, mental stress, and antigen-antibody reaction. Fibrinolytic activities are reported mainly in association with fibrinolysis in saliva, mandibular cyst walls and gingival tissues.
The present study, examined the relationship between the inflammation process and plasminogen activator activity, using gingival tissue, saliva and blood samples collected from the rats with experimentally induced gingivitis.

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We have found that human parotid saliva contained the substances responsible for releasing histamine. They were basic peptides whose histidine contents were extremely high. Human parotid saliva has previously been shown to contain a group of histidinerich polypeptides (HRPs). However, their function is unclear and the sequence of the individual HRPs have not been determined. In this report, we further purified one of the HRPs, F-A with histamine-releasing property and estimated its amino acid sequence.

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It is recognized that the rat submandibular gland consists of five distinct parenchymal segments, acini, intercalated ducts, granular ducts, striated ducts and excretory ducts, and the function of these segments are different from each other. These parenchymal components can be separated from salivary glands of the rat following a microdissection method devised by us.
Using these dissociated preparations and electrophoretic techniques, we found that the functional segments of the submandibular gland of intact rats contain several glycoprotein species; some of these have a characteristic response to stimulation and are secreted into submandibular saliva in a diffel ent manner depending on the kind of drug, such as, cholinergic agonists and aor β-adrenoceptor agonists.
The present study was designed to observe the secretory pattern of these characteristic glycoprotein species in acini and convoluted granular tubules following stimulation by methoxamine, because such observations have not yet been reported. For this purpose, changes in the salivary flow rate and the composition of glycoprotein species were followed during salivation induced by an aladrenergic agonist, methoxamine.

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