The present study was designed to determine whether the submandibular glands of weanling rats respond to α1-and β-adrenoceptor agonists in the same manner as glands from adult animals, to determine the doses of these agonists, which give the maximum responses, and using isoelectric focusing and twodimensional electrophoreses, to determine whether proteins in submandibular saliva are modified posttranslationally as they pass through the duct systems. All of the agonists used were potent sialogogues and were given i.p. over a wide range of doses. The volumes of saliva, the total output of protein and the relative activity of protease progressively increased with increasing doses of each agonist. The optimal dose of each agonist was neither low nor excessively high. The submandibular glands of weanling rats seem to be as fully developed for fluid and protein secretion as those of adult rats. In addition, no special protein was involved in saliva secreted by the submandibular glands of weanling rats at any of the doses of the various agonists used here. However, some proteins in submandibular saliva of 25-or 35-day-old rats, when compared with extracts of the submandibular gland, appeared to have been modified posttranslationally or degraded by proteases while passing through the duct systems of the submandibular glands of weanling rats.

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The present study was performed to investigate the morphological changes that occur in thegranular convoluted tubule and acinar cells of the mouse submandibular gland after the injection ofmethoxamine solutions into the abdominal cavity of male ICR mice.
When a highly concentrated solution of methoxamine was given, the number of secretory granulesdischarged from the granular convoluted tubule cells increased and the time required for secretion wasreduced. As discharge increased, several vacuoles and dense granular-structures appeared in the cytoplasm. The three-dimensional structure obtained through computer analysis showed that a large majority of thevacuoles opened into the lumen of granular convoluted tubules. Therefore, the vacuoles seemed to haveoriginated from the limiting membranes of secretory granules after exocytosis.
Positive reactions to Peanut agglutinin (PNA) and Soybean agglutinin (SBA), which did not occur in thelimiting membranes of secretory granules before exocytosis, were observed in membranes of the vacuoles. Deposition of PNA and SBA in the vacuoles may indicate the presence of sugar residues, which were maskedin the secretory granules before their contents were released.
Lectin staining and transmission electron microscopy revealed that the dense granular-structures corresponded to secondary lysosomes breaking down the retrieved membranes.

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To investigate the mechanisms of the many favorable properties of chitin membrane in woundhealing, human peripheral monocytes were cultured on chitin membrane or other wound dressing materials, and the chemical mediators from macrophage, including prostaglandin E₂ and interleukin 1, were analyzed.These mediators were detected in the supernatants of the macrophage cultures. The chitin-induced productionof chemical mediators from macrophages was less than that induced by the other dressing materials.These results suggest that each wound dressing material has a different capability of inducing th productionof inflammatory chemical mediators by macrophages, and that the favorable properties of chitin in woundhealing might be related to its lower capability to induce localized inflammation.

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The loss of trabecular bone in the ovariectomized (OVX) rat provides a useful experimentalmodel of postmenopausal osteoporosis. In the present study, two bone-modulating compounds, NSAID (flurbiproten, FBP) and chemically-modified non-antimicrobial tetracycline (TC-1) were tested in thismodel. Ninety days after OVX, 3-month-old female rats were distributed into the following groups: non-OVX controls, sham-treated OVX, TC-treated OVX (5 mg p. o./day), FBP-treated OVX (0.3 mg p. o./day) and combination (TC plus FBP)-treated OVX (“combo”) groups. After 21 days of therapy, the proximalends of femurs were dissected and processed for light microscopic, fluorescence microscopic, backscatteredelectron microscopic, and transmission electron microscopic examination. In sham-treated OVX rats, trabecular bone volume/unit area was only 54.3% of that observed in non-OVX controls; this bone loss wasclearly associated with increased numbers of osteoclasts (p<0.05) along bone trabeculae. In contrast to thetrabecular area, cortical bone volume was not significantly reduced in these OVX rats. In this short-termtreatment study, both FBP-alone and combo therapy significantly (p<0.05, p<0.01) inhibited trabecularbone loss in OVX rats. Both therapies also significantly reduced the number of osteoclasts (p<0.05). On theother hand, both TC-alone and combo therapy appeared to increase bone deposition (p<0.05) at theendosteal surface of the cortical bone in OVX rats. These results suggest that 1) TC enhances osteoblasticbone formation in trabecular and cortical bones, and 2) FBP reduces the number of osteoclasts, and thereby inhibits osteoclastic bone resorption in the trabecular area.

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The multi-functional protein osteonectin is widely distributed throughout many tissues. It plays a role in tissue morphogenesis and affects the interaction between cells and the extracellular matrix.
Osteonectin may also play an important role in dentin mineralization, since it has high affinity for Ca and hydroxyapatite. Expression of the genes for osteonectin and type I collagen, which is a major dentin organic matrix protein during dentinogenesis in mouse incisors, was studied by in situ hybridization using RNA probes to clarify the function of osteonectin during dentinogenesis. Apparent expression of osteonectin gene was detected in dental papilla cells from the horizontal region of the cervical loop, and was maximal in preodontoblasts and early-secretory-stage odontoblasts. Expression in secretory odontoblasts was weaker than that in preodontoblasts, and gradually decreased toward the incisal edge.
Intense osteonectin expression reappeared in the region of osteodentin formation. In the periodontal ligament, fibroblasts associated with periodontal fibers orientated longitudinally to the tooth axis, while cementoblasts and osteoblasts showed intense osteonectin expression. Expression of the type I collagen gene was essentially the same as that for osteonectin. Reactions using sense osteonectin and type I collagen RNA revealed no specific localization.
These results suggest that osteonectin plays an important role in matrix formation and mineralization of dentin, as well as in turn over of the periodontal ligament.

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Neural activity in the anterior lateral line nerves (NLLa) of the carp, Cyprinus carpio L., was studied. Whole nerve experiments revealed that the NLLa were sensitive to salts, acids and quinine-HCl, and the threshold for acid was much lower than that in the communis. Single unitary discharges in the intracranial NLLa trunks were also studied using microelectrode techniques. Fifty of the 51 recorded activities were facilitated by NaCl, acetic acid, quinine-HCl or sucrose, and only one was inhibited by the latter two. Twelve units were also tested with betaine, extract of silk worm pupae and ten amino acids, to which they did not respond, except for an inhibitory response to some of the amino acids. Forty eight of the 51 chemosensitive units also responded to mechanical stimulation of the facial skin. However, these units were slightly less sensitive to this stimulation than units which responded only to mechanical stimulation. Chemosensitive neurons did not innervate the lip, barbel regions or canal organs of the face, which were sensitive only to mechanical stimulation. Ten of the 51 units were also found sensitive to thermal stimulation. These results suggest that the role of the NLLa is clearly different from that of the facial (gustatory) nerves.

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Moody & Montgomery (1934) found fused mandibular deciduous incisors only among females in 3 generations of 3 Caucasian families, and concluded that this condition was transmitted only to females and was usually transmitted only through females who were themselves affected. McKusick suggested that fused teeth are a Mendelian autosomal dominant trait, confusing them with the single giant maxillarycentral incisor in holoprosencephaly. Although fused teeth are reportedly 6-10 times more frequent in Mongoloids than in Caucasians, there have been few reported hereditary cases of fused teeth in Japan, which casts doubt on whether fused teeth are indeed an autosomal dominant trait. We studied deciduous and permanent fused teeth. However, although deciduous fused incisors were about 10 times more frequent than permanent fused incisors, it was difficult to confirm whether the parents of the affected children also had fused deciduous incisors. Almost all of the parents of the affectedchildren had normal permanent incisors. Therefore, we only considered permanent fused incisors in this hereditary study. We investigated Japanese families which included 15 males and 26 females with permanent fused incisors. This condition was found in both the parents and children in only 4 families (9.8%). These findings conflict with the notion that fused teeth are a Mendelian autosomal dominant trait. Moreover, all of the reports of fused incisors in Caucasians, including that of Moody et al can be clearly explained by autosomal recessive inheritance.
These findings strongly suggested that the inheritance of permanent fused teeth was of autosomal recessive trait.

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This study was undertaken to investigate patterns of neuronal activity during mastication in neurons in the first somatosensory cortex (SI) that responded to mechanical stimulation of the teeth. A total of 163 neurons with a receptive field in the intraoral cavity were recorded in the SI of 8 conscious cats. Twenty-three percent (38) of intraoral SI neurons responded to tooth and/or teeth tapping and strong pressure, but not to physical stimulation of the gingiva around the teeth; these were considered periodontal SI neuron (P-SIn). Sixty-six percent of P-SIns showed a rhythmical burst firing (RB) during mastication, 29% showed temporary burst firing (TB), and 5% showed sustained burst firing (SB). P-SIns were divided into two types (type I and II) based on whether they responded to medium (von Frey hair No.3 and No.4) or strong mechanical stimuli (von Frey hair No.5 and No.6). P-SIns of type I were recorded at areas 3a (70%) and 3b (30%), and all of the type II P-SIns were recorded at area 3a. Furthermore, almost all of the RB and SB P-SIns were of type I, and all TB P-SIns were of type II.
These findings suggest that type I P-SIns monitor the movement of the tongue and food, while those of type II discriminate the texture of food during mastication.

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Human benign tumors were transplanted to 31 nude mice. Tissues from 6 cases of ameloblastoma and 1 case of pleomorphic adenoma were transplanted to the subcapsular space of the kidney and the subcutaneous space of normal 8-week-old KSN male nude mice. Animals were sacrificed periodically and serial sections were made for histological examination. Transplantation was successful in 3 cases of solid type ameloblastoma and in the case of pleomorphic adenoma. In cystic type ameloblastoma, the transplants gradually became smaller and disappeared in 2 months. These results suggest that several conditions are indispensable for successful transplantation. The morphological characteristics of transplanted tumor tissues were basically similar to those of the primary tumors.

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