Localization of a low Mr GTP-binding protein, rap1 protein, in plasma membranes and secretory granule membranes of rat parotid gland

Subcellular fractions were prepared from rat parotid gland by sequential centrifugation, Percoll gradient centrifugation and divalent-cation precipitation, and the localization of a low Mr GTP-binding protein, rap1 protein (rap1p) was analyzed by immunoblotting using a specific antibody. rap1p was found to be located in apical and basolateral plasma membranes, and secretory granule membranes in rat parotid gland. On the other hand, the beta gamma subunits of heterotrimeric Gt protein was localized in plasma membranes but not in granule membranes.

Pulpal and periapical tissue reactions after experimental pulpal exposure in rats

The purpose of this study was to investigate histologically and histometrically the changes in pulpal and periapical tissues after pulpal exposure in rats. All animals received a pulpal exposure in the left mandibular first molar. Animals were killed at 1 to 56 days after pulpal exposure, and their mandibles were evaluated histologically and histometrically. Histologically, pulpal necrosis extended gradually from the upper part of the pulpal tissue to the apex, with inflammation starting in the periapical tissue at an early stage. As the periapical lesion developed, alveolar bone and cementum resorption was also found. Histometrically, the length of pulpal necrosis increased gradually from 1 to 28 days. The vertical length of the periapical lesion after 14 days was significantly increased, while the horizontal length and the overall area after 7 days were also significantly increased. The periapical lesion extended in a mesiodistal direction at first and then in a vertical direction before expansion ceased.

Suppression of development of anti-nuclear antibody and glomerulonephritis in NZB x NZWF1 mice by persistent infection with lactic dehydrogenase virus: possible involvement of superoxide anion as a progressive effector

The development of anti-nuclear antibody (ANA) and glomerulonephritis (GN) in autoimmune NZB x NZWF1 mice was suppressed by persistent lactic dehydrogenase virus (LDV) infection. This observation was used to study a possible pathogenetic role for the toxic oxygen radical, superoxide anion (O2-), in the progression of ANA and GN. Compared to macrophages from NZB x NZWF1 mice with LDV infection, macrophages from uninfected NZB x NZWF1 mice exhibited an age-related and drastic increase in O2- production in association with the development of the ANA and GN (representing the late stage of disease). NZB x NZWF1 mice with or without LDV infection were then given the O2- scavenger superoxide dismutase (SOD) during the late stage of the disease. Treatment of uninfected NZB x NZWF1 mice with SOD (10,000 units/mouse/day for 3 weeks) protected animals from the development of ANA and GN. SOD treatment also suppressed the development of the lesions in NZB x NZWF1 mice with LDV infection. Our findings suggest that O2- may, at least in part, contribute to the development of ANA and GN in the late stage of disease, and that decreased O2- production in NZB x NZWF1 mice with LDV infection may be responsible for the suppression of the development of ANA and GN in the late stage of the disease.

Distribution profiles of fluoride in three different kinds of rat bones

The study was performed to reveal the detailed distribution profiles of fluoride in three different kinds of rat bone--humerus, vertebral arch, and parietal bone--and to compare this with the histological appearance of each bone type. Two groups of Wistar rats were provided water ad libitum containing 0 and 100 ppm fluoride, respectively, for 24 weeks. The fluoride distribution profiles across the bone of the three different bones from the outer to the inner surface were determined by means of an abrasive micro-sampling technique. In control animals, both humerus and parietal bones showed higher concentrations at the periosteal and endosteal surfaces, while the vertebral arch showed additional high levels in the middle (containing trabecular bone) of the tissue. In exposed animals, fluoride levels increased greatly in all three bone types. The vertebral and parietal fluoride distribution profiles were relatively unchanged, although humerus fluoride increased from periosteum to endosteum. The differences in fluoride distribution profiles were apparently related to the histological appearances of these bones. The surface area of bone available and the extent of vascularity appear to affect fluoride uptake.

Unusual gingival enlargement with rapidly progressive periodontitis. Report of a case

A 15-year-old female patients suffered from recurrent unusual enlargement of the gingiva together with rapidly progressive alveolar bone loss. The enlarged gingiva completely covered her anterior teeth and protruded from the mouth. Marked inflammatory edematous tissue, which predominantly contained plasma cells, was observed in the connective tissue. Rapidly progressive alveolar bone loss was observed radiographically. The serum antibody titer to Porphyromonas gingivalis, measured by ELISA, was much higher than that in healthy individuals. The diagnosis was unusual gingival enlargement with rapidly progressive periodontitis. Conventional periodontal therapy, including plaque control, scaling, root planing, and surgical removal of the soft tissue, did not produce complete healing of the gingival lesion, although recurrence of gingival enlargement and further loss of the periodontal attachment level were well controlled. After the periodontal treatments, the serum antibody titer to P. gingivalis decreased to normal levels. This unusual gingival enlargement was considered due to systemic factors that exaggerated the gingival response to local irritation and altered the usual clinical features of chronic gingivitis; local plaque irritation produced the extensive and recurrent enlargement of the gingiva. Under these circumstances, infection or overgrowth of periodontopathic bacteria, including P. gingivalis, might occur and the alveolar bone loss would then advance very rapidly.

Retardation of mouse odontoblast differentiation by heparin in vitro

The effect of heparin was studied histologically and immunohistochemically. Tooth germs from 15-day-old mouse embryos were cultured with or without heparin. After 6 days of culture in control medium, mesenchymal cells underlying the inner enamel epithelium had differentiated into odontoblasts and secreted predentine. In medium with heparin, mesenchymal cells were undifferentiated. In medium with other glycosaminoglycans such as chondroitin sulphate, dermatan sulphate or hyaluronate, tooth germs were similar to those in control medium, as were those in medium with heparin-Sepharose absorbed serum. After 12 days of culture in the heparin medium, mesenchymal cells in some cusps had differentiated into odontoblasts and secreted predentine but in other cusps remained undifferentiated. Immunohistochemically, exogenous heparin did not prevent the deposition of type IV collagen, laminin and fibronectin in the basement membrane and extracellular matrix. These results suggest that exogenous heparin retards differentiation of odontoblasts but not by disruption of the basement membrane nor inactivation of heparin-binding growth factors present in serum.

Properties of plasma membrane-induced amylase release from rat parotid secretory granules: effects of Ca2+ and Mg-ATP

A secretory granular fraction (SG) and a plasma membrane rich fraction (PM) have been isolated from rat parotid gland by differential and Percoll gradient centrifugation. With these two fractions, a cell-free interaction system has been reconstituted to clarify the exocytotic interaction between the secretory granules and plasma membranes, and the conditions of amylase release from SG have been characterized in vitro. The addition of PM into this assay system induced a rapid and transient release of amylase from SG. Some other membranes such as erythrocyte ghosts also mimicked the effect of PM. This release was increased by Ca2+, but was not completely blocked by EGTA. Simultaneous addition of 1 mM ATP with 1 mM MgCl2 (Mg-ATP) in the presence of Ca2+ reduced this release. However, in spite of the existence of Mg-ATP, the stimulation of PM-induced amylase release was caused by Ca2+ in a concentration-dependent manner (10(-7)-10(-3) M). These results suggest that Ca2+ and Mg-ATP should participate as important regulators in the exocytotic interaction between secretory granules and plasma membranes in this system. Furthermore, the differences between our system and intact cells are also discussed.

Parasitism of Toxocara canis larvae in Japanese quails by inoculation of the ascarid eggs

The distribution of T. canis larvae and pathological changes caused by them were studied in Japanese quails orally inoculated with 1,500, 4,000 or 15,000 embryonated eggs. Larvae were distributed mainly in the liver and, to lesser extent, in the muscles, brain, eyes and other organs. The number of larvae varied from 7 to 3,346, and from 1 to 288 in the liver and muscles (breast and legs), respectively. A small number of larvae were also recovered from the heart, gizzard, brain and eyes. In the groups of quails inoculated with 4,000 or 15,000 eggs, small white foci were observed on the surface of the liver 6 or 12 hr after inoculation. Histopathological examinations revealed necrotic lesions, leukocytic infiltration, granuloma and nodular lesions. The pathological changes became more serious with the large size of inoculum and days after inoculation.

The iron chelator deferoxamine prevents cisplatin-induced lipid peroxidation in rat kidney cortical slices

We evaluated the effect of the iron chelator deferoxamine on lipid peroxidation produced by the nephrotoxic antineoplastic drug cisplatin in rat kidney cortical slices. The addition of deferoxamine to the incubation medium prevented such lipid peroxidation in the incubated slices. Treatment of rats with deferoxamine inhibited the increase in lipid peroxidation caused by cisplatin in the medium. These results suggest that iron may be a causal agent of cisplatin-induced lipid peroxidation.

[Changes in granulocyte elastase caused by the use of ulinastatin during anesthesia for renal transplantation]

In patients with renal failure, releases of chemical mediators having inhibitory influences on organs and circulatory system have been observed. Therefore, in long-term dialysis patients, it is necessary to consider the biocompatibilities of the equipment for dialysis. On 13 cases of renal transplantations, we measured the pre- and post-operative changes of granulocyte elastase (GE) and evaluated the effect of ulinastatin. The renal transplanted patients receiving a long-term dialysis showed higher GE values than that of normal patients even before the operation. During the anesthesia, GE increased gradually and further increased after the operation. In patients given ulinastatin during anesthesia, the increase in GE during the operation was suppressed but an increase after the operation was observed. The renal transplanted patients are easily infectible. Therefore, it is useful to measure GE pre- and post-operatively for earlier diagnosis of the postoperative infection and septicemia. The administration of ulinastatin can inhibit the increase of GE. It seems that ulinastatin increases renal blood flow and improves renal function.

[Rapidly progressive periodontitis combined with plasma cell gingivitis: a case report]

A case of rapidly progressive periodontitis combined with plasma cell gingivitis with marked enlargement of the gingiva was presented. Clinically, in the plasma cell gingivitis, the gingiva appear red, friable and bleed easily; usually it does not induce loss of attachment. Histologically, a dense infiltration of the normal plasma cells in the connective tissue is a common finding. A hypersensitivity reaction to some antigens, often flavorings or spices, is generally recognized. In this case, a rapidly progressive loss of attachment was observed, so rapidly progressive periodontitis was diagnosed. Differential diagnosis of the plasma cell gingivitis could be determined by histological and ultrastructural examination. Allergens, however, could not be identified. Conventional periodontal therapy, including intensive plaque control, could not cure the plasma cell gingivitis completely but recurrence of gingival enlargement and loss of attachment could be well controlled.

Experimental odontogenic tumors produced by ethylnitrosourea injections and mechanical injuries

The present study was carried out to investigate odontogenic tumor induction in the rats by injections of carcinogen N-ethyl-N-nitrosourea (ENU) coupled with incisional wounds. The animals which received local injections of ENU in the region of incisor tooth germ of the right mandible every other day for 19 days after birth coupled with incisional wounding in the same region at 2 and 8 days, developed odontogenic carcinomas. However, the animals which were given local injections of ENU in the region of incisor tooth germ but did not receive incisional wounds, showed no pathologic changes. The animals which received both local injections of physiologic salt solution and incisional wounds in the same manner as mentioned above, did not exhibit any pathologic changes. The present results indicate that local administration of carcinogen ENU coupled with mechanical injuries, namely incisional wounding, caused the production of odontogenic carcinomas in the incisor region of the mandible in rats.

Ca(2+)-independent phospholipase A2 activity associated with secretory granular membranes in rat parotid gland

Phospholipase A2 activity was detected in a secretory granular fraction (SG) purified by Percoll gradient centrifugation from rat parotid gland using [3H]phosphatidylcholine (PC) as a substrate. High activity of this enzyme was observed at neutral pH. The enzyme was activated by Triton X-100 and did not require Ca2+ for its activity. In the absence of Ca2+, its apparent Km for exogenous PC was 28 microM while it was slightly increased by adding 5 mM CaCl2 (73 microM). Furthermore, the enzyme was located essentially in a granular membrane fraction separated from granular lysate. The deacylation activities were also detected in other subcellular fractions, which showed a different detergent-susceptibility or pH-dependency from that in SG. These results suggest that secretory granules have membrane-bound phospholipase A2 which has properties different from that found in other organelles.

Developmental disturbance of rat cerebral cortex following prenatal low-dose gamma-irradiation: a quantitative study

Pregnant rats were exposed to a single whole-body gamma-irradiation on Day 15 of gestation at a dose of 0.27, 0.48, 1.00, or 1.46 Gy. They were allowed to give birth and the offspring were killed at 6 or 12 weeks of age for microscopic and electron microscopic examinations of the cerebrum. Their body weight, brain weight, cortical thickness, and numerical densities of whole cells and synapses in somatosensory cortex were examined. Growth of the dendritic arborization of layer V pyramidal cells was also examined quantitatively with Golgi-Cox specimens. A significant dose-related reduction in brain weight was found in all irradiated groups. Neither gross malformation nor abnormality of cortical architecture was observed in the groups exposed to 0.27 Gy. A significant change was found in thickness of cortex in the groups exposed to 0.48 Gy or more. Cell packing density increased significantly in the group exposed to 1.00 Gy. Significant reduction in the number of intersections of dendrites with the zonal boundaries were found in the groups exposed to 0.27 Gy or more. There was no difference in the numerical density of synapses in layer I between the control and irradiated groups. These results suggested that doses as low as 0.27 Gy could cause a morphologically discernible change in the mammalian cerebrum.

Experimental epithelial dysplasia produced by excisional wounding and application of Trp-P-2 in the hamster tongue

All 10 groups of hamsters received excision of the tip of tongue. Subsequently, 3 groups in which tongues were treated with Trp-P-2 (3-amino-1-methyl-5H-pyrido[4,3-b] indole) and then again excised in their tips followed by no treatment or by additional applications of DMSO or Trp-P-2, showed moderate to severe epithelial dysplasia. One group in which tongues were not treated and then again excised followed by applications of Trp-P-2, exhibited very slight epithelial dysplasia. However, one group in which tongues were treated with DMSO and then again excised followed by additional applications of DMSO, did not show any pathological changes. The remaining 5 groups in which tongues were treated with DMSO or Trp-P-2 or received no treatment and then not excised followed by no treatment or by additional applications of DMSO or Trp-P-2, also did not show any pathologic changes. These results clearly indicated that Trp-P-2 treatment together with two times of excisional wounding could produce lingual epithelial dysplasia in hamsters.

18q-syndrome with cleft lip and palate. A clinically diagnosed case

A case of a child with 18q-syndrome was encountered. The patient presented cleft lip and palate, narrow auditory canals, overlapping fingers, undescended testes and micropenis. Chromosome analysis demonstrated partial deletion of the long arm of one chromosome 18 in the patient and normal chromosomes in the parents. A cheiloplasty for repair of bilateral complete cleft lip was performed.

Sensitive phases for teratogen-induced developmental defects in the brain

Developmental stage-dependent susceptibility to teratogens and sensitive period can be regarded as one of the essential points which characterize teratogenesis. In this paper, emphasis is given to a review of our studies on the critical developmental stage for induction of histogenetic disorders of the cerebral cortex and on the high vulnerability of developing neural cells to teratogenic agents. The undifferentiated ventricular cells in the mammalian fetal telencephalon are particularly vulnerable to various cytotoxic agents at the time when the ventricular cells start to differentiate into cerebral cortical neurons and the cortical plate appears. This period is day 13 of gestation in mice, day 15 in rats and 8 weeks after fertilization in humans. This developmental stage of the brain corresponds to the period of highest sensitivity for induction of cerebral cortical disorders observed postnatally both in laboratory animals and in humans. One of the significant factors determining the period of highest sensitivity of the ventricular cells could be a certain initial phase of cytodifferentiation in G1 and G0 phase cells prior to their actual morphological differentiation.

Cisplatin-induced injury to calcium uptake by mitochondria in glutathione-depleted slices of rat kidney cortex

Changes in functional activities of mitochondria from kidney cortical slices incubated with cisplatin and the glutathione depletor diethylmaleate were examined. Diethylmaleate, which decreased the glutathione level in the slices, enhanced the cisplatin-induced decreases in glutathione level and calcium uptake in the mitochondria. The movement of cisplatin into mitochondria in the slices was not affected by diethylmaleate. These results suggest that the depressions in glutathione level and calcium uptake by cisplatin in mitochondria are enhanced by a decrease in cytoplasmic glutathione.

[Effects of combination chemotherapy with topical application of 5-FU ointment to mice's tongue and UFT]

After oral administration of UFT and lingual topical application of 5-FU ointment to normal mice, the change of the concentration of 5-FU and Uracil in the tongue, liver and blood serum were studied. We compared with UFT only group, 5-FU ointment only group and the both combination chemotherapy group. 1. As for the tongue concentrations, 5-FU levels in both combination chemotherapy group and 5-FU ointment only group were higher compared to UFT only group. There was no difference between combination chemotherapy and 5-FU ointment only group. Uracil at 21-days in combination chemotherapy group were higher than others. 2. The liver concentrations of 5-FU at 21-days was significantly higher. 3. The blood serum concentrations of 5-FU in both combination chemotherapy and 5-FU ointment only groups revealed similar results. Thereafter, combination chemotherapy in oral region with topical application of 5-FU ointment and UFT may be effective.

Fetal laser surgery in genetic polydactyly mice

The first digital ray of the hindlimb plate in Slc:ICR mouse fetus was irradiated with 2 watts argon laser beam for 0.3 sec after releasing from the abdominal cavity and envelop of uterine myometrium on day 13 of gestation, and then the fetuses were allowed to develop in the abdominal cavity contacting with the uterus via the placenta exo utero until term. ICR mouse fetuses which received fetal laser surgery lost their first digits completely, resulting in 4-digit hindfoot on day 18 of gestation. The homozygous Polydactyly Nagoya (Pdn/Pdn) mice exhibit 1-3 extra digits both in the fore- and hindlimbs preaxially. The extra digital rays in the left hindlimbs of Pdn/Pdn fetuses were irradiated with 2 watts argon laser beam for 0.3 sec on day 13 of gestation exo utero. The left hindlimbs of the Pdn/Pdn fetuses which received fetal laser surgery lost their preaxial extra digits on day 18 of gestation, resulting in 5 digits, though their 1st digit was triphalangia. The combination of a laser instrument with the fetoscope and/or ultrasound scanner may promote the fetal surgery of congenital anomalies in humans.

Nephrotoxicity of a new platinum compound, 254-S, evaluated with rat kidney cortical slices

The addition of a new compound containing platinum, 254-S, an antineoplastic agent, to medium had no effect on p-aminohippurate (PAH) accumulation, gluconeogenesis, or potassium and ATP concentrations in rat kidney cortical slices at the concentrations tested, up to 10 mM. At 1 mM, cisplatin, used for comparison, significantly decreased all of these biochemical indices in the slices. Administration of 254-S at a low dose (10 mg/kg i.v.) to rats decreased the ability of the slices to accumulate PAH and to maintain the potassium concentration, without affecting levels of urea or creatinine in blood plasma. 254-S at a high dose (20 mg/kg i.v.) or cisplatin at 5 mg/kg (i.v.) also decreased these indices in the slices, and affected urea and creatinine in blood plasma. These results suggested that use of the renal slice technique gives data useful for the evaluation of the nephrotoxicity of 254-S, and that PAH accumulation and the potassium concentration in slices from rats treated with 254-S are indicators of nephrotoxic damage.

Distribution of fluoride concentration in the rat's bone

The present study was undertaken to determine the fluoride distribution profile in the rat femur. Male Wistar rats were divided into four groups and given water containing 0, 25, 50, and 100 ppm of fluoride, respectively, for 10 weeks. The fluoride distribution from the periosteum to the endosteum was determined in each specimen after sampling using the abrasive microsampling technique. In the outer circumferential lamellae, the concentration of fluoride was relatively high in the periosteal layer and then decreased gradually towards its interior. In the haversian and interstitial lamellae, it was lower and roughly constant through the tissue. In the inner circumferential lamellae, it rose again to reach the highest level towards the endosteal surface. Fluoride concentration throughout the cortex increased significantly with increasing intake of fluoride. These increases were especially marked at periosteal and endosteal surfaces.

Developmental brain abnormalities accompanied with the retarded production of S-100 beta protein in genetic polydactyly mice

The homozygotes of a mouse strain with genetic polydactyly (Polydactyly Nagoya, Pdn) exhibit various brain malformations including exencephaly in about 20%. In the present report, the brains of homozygotes (Pdn/Pdn) which were not exencephalic were examined morphologically and biochemically. Homozygous newborn brains showed hydrocephaly, some gyri on the cerebral hemisphere, absence of the corpus callosum, absence of the commissura anterior, absence of the fornix and commissura fornicis, protuberance of the cortical tissue from the brain surface, and abnormal architecture of the hippocampus. An irregular mass of olfactory nerve was observed on the cribriform plate, and the olfactory bulb was deficient. From these findings, we considered Pdn/Pdn as a kind of arhinencephalic mouse. Nervous tissue-related proteins, S-100 alpha, S-100 beta, creatine kinase B (CK-B), neuron-specific gamma-enolase, guanosine triphosphate binding proteins (Go alpha, Gi2 alpha and G beta) were immunoassayed in the cerebrum of Pdn/Pdn embryos and newborns. Among the protein analysed, only S-100 beta of Pdn/Pdn showed a significantly lower level than that of +/+ cerebrum during the observation period. The newborn brains were examined immunohistochemically using S-100 alpha, S-100 beta, CK-B, Go alpha and NSE antibodies. We could find no differences in the staining patterns among the Pdn/Pdn, Pdn/+ and +/+ brains.

Biochemical and physical analysis of subcellular membranes in rat parotid gland enlarged by chronic isoproterenol administration

1. Chronic administration of isoproterenol caused similar alterations of membrane lipid profile in at least two rat parotid subcellular fractions, secretory granular and microsomal. 2. Typical changes in phospholipid classes and fatty-acyl chain groups were an increase of phosphatidylcholine and a decrease of sphingomyelin, and an increase of octadecadienoyl chain and a decrease of eicosatetraenoyl chain, respectively. 3. Electron spin resonance study showed that the isoproterenol-treatment also affected a membrane physical property, which may be through these compositional changes in membrane constituents.