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To elucidate the normal development and growth of Mongolian gerbils, the timing and sequence of the appearance of ossification centres within foetuses were investigated. Average foetus body weight and tail length on the 15th day of pregnancy were found to be 0.042 g and 6.2 mm, respectively. For the 25th day of pregnancy, these measurements were 2.601 g and 29.4 mm, respectively. The body weight and tail length of foetuses increased significantly from the 20th day of pregnancy. Also, the first ossification centre of Mongolian gerbil foetuses appeared in the clavicle at the 17th day of pregnancy. The order in which ossification centres appeared in Mongolian gerbils resembles the pattern for rats and mice, except in some areas of the skull. Except for the clavicle, in which ossification centres appeared rather early, most ossification centres appeared in the last quarter of pregnancy. These results suggest that Mongolian gerbil foetal development is near completion by the last gestational stage. Also, ossification centres appear sooner in the skull and nasal bones than in other rodents. more...

The susceptibility to Leptospira interrogans serovar copenhageni in Mongolian gerbils treated with 10 micrograms of serum thymic factor (FTS) 1 day before infection was examined. Susceptibility of gerbils treated 5 times with 10 micrograms of FTS was also investigated. Mortality of FTS-treated gerbils was significantly lower than that of controls when small challenge doses were used. To analyse the FTS-induced resistance to leptospiral infection, natural killer (NK) cell activity and macrophage activity were studied. Macrophage activity was unaltered but NK cell activity was enhanced in FTS-treated gerbils, with or without leptospiral infection. Since no side-effects of FTS were observed, this compound should be considered for the treatment of leptospirosis. more...

In Mongolian gerbil, morphological changes with age in the content of endocrine cells in the pancreatic islets were analyzed and their relation evaluated by an oral glucose tolerance test. The glucose level 2 hours after glucose administration was 125 +/- 5 mg./d1 in the young group and 103 +/- 4 mg./d1 in the old group. In the dorsal portion, B cells were mainly observed in the central area of the islets, surrounded by circular layers of A cells in the peripheral area. Between the A cells and B cells, D cells were scattered or present in layers. A few PP cells were present in the peripheral area of the islets. In the ventral portion, only a few A cells were observed in the peripheral area of the islets, and B cells were surrounded by PP cells. Secretory granules of A cells generally had an electron-dense spherical core in the limiting membrane. The halo between the limiting membrane and core in A cells was narrower than that in B cells. Secretory granules of B cells were larger than those in A cells, and the core was less electron-dense, and the halo was wider. Secretory granules of D cells were similar in size to those of A cells; the core showed low electron density, and the halo was very narrow. Granules of PP cells resembled those of A cells, but the electron density of the core was slightly lower. The gerbils showed changes in glucose tolerance, the size of the pancreatic islets, the percentage of B cells, and of A cells in the dorsal portion with age.(ABSTRACT TRUNCATED AT 250 WORDS) more...

Chemiluminescence studies on superoxide generation by phagosomes using opsonized zymosan showed the highest fluorescence in murine splenic macrophages among four different kinds of splenic or peritoneal macrophages from mice or gerbils. Murine splenic macrophages phagocytized two to three times more latex particles than gerbil splenic macrophages, but peritoneal macrophages did not show a significant difference in phagocytic activity between mice and gerbils. Phagocytosis by macrophages was determined by a technique based on measurement of the release of hydrogen peroxide and myeloperoxidase from phagosomes using microspheres conjugated with 3-(p-hydroxyphenyl) propionic acid (HPPA-MS). HPPA is a substrate of lysosomal myeloperoxidase. The fluorescence of HPPA-HPPA-MS produced by phagocytized HPPA-MS was measured with an immunoreaction analysis system (IMRAS), and the enzyme activities of the four different kinds of peritoneal or splenic macrophages from mice and gerbils were compared. All four kinds of macrophages produced HPPA-HPPA-MS in their phagosomes during phagocytosis and murine splenic macrophages showed the highest level of enzyme activity. more...

Atrial natriuretic peptide (ANP) levels in cardiocytes and plasma were examined by using immunohistochemistry, electron microscopy, and radioimmunoassay in non-obese diabetic mice (NOD). Cardiocyte ANP mRNA expression was measured by the polymerase chain reaction method. ANP immunoreactivity in the auricular cardiocytes was more prominent in hyperglycemic mice (NOD-h) than in normoglycemic mice (NOD-n). Ultrastructural examination showed that auricular cardiocytes of the NOD-h group contained more cytoplasmic granules than cells of the NOD-n group. Ultrastructural morphometry indicated that the number of granules per auricular cardiocyte was significantly larger in the NOD-h group than in the NOD-n group (P less than 0.01), whereas the granule diameter was significantly smaller in the NOD-h group (P less than 0.01). Radioimmunoassay showed that ANP levels in the NOD-h auricular cardiocytes were significantly higher than those in the NOD-n cardiocytes (P less than 0.01); the opposite was true in plasma. Cardiocyte ANP mRNA expression was lower in the NOD-h group than in the NOD-n group. more...

In the hamster, guinea pig, rabbit, dog and cat, the right and left atria and ventricles were examined by immunohistochemistry, and the right auricular cardiocytes were studied by transmission electron microscopy. Moreover, ANP-granules in the cardiocytes were analyzed by ultrastructural morphometry. Immunohistochemically, the most intensely ANP-reactive cardiocytes were localized in the right auricle, particularly more prominent in the hamster and guinea pig than in the rabbit, dog and cat. The immunoreaction in the dog and cat was weaker than that in the rabbit. ANP-immunoreactivity was not detected in the ventricular myocardium of any of all species examined, but was occasionally observed in the subendocardium of the ventricular septum. Ultrastructurally, ANP-granules were localized principally in the perinuclear region associated with the Golgi apparatus and scattered throughout the sarcoplasmic layers. The Golgi apparatus of the cardiocytes was better developed in the hamster and guinea pig than in the rabbit, dog and cat. It was poorly-developed in the dog and cat. By ultrastructural morphometry, the number of granules was greatest in the hamster followed by the guinea pig, rabbit and dog or cat, in this order. On the other hand, the diameter of granules was largest in the guinea pig and reduced via the hamster to the rabbit. The diameter was significantly smaller in the dog than in the rabbit. The diameter of granules of the cat was lay between the rabbit and dog. more...

In Mongolian gerbils, prostatic buds were found in female fetuses at the 23rd day of gestation. In the mothers the well-developed prostate gland consisting of a paired lobes was situated on either side of the neck of the bladder. more...

During pre-and postnatal development, the atrial natriuretic peptide (ANP)-granules in the right and left auricular cardiocytes of Syrian hamsters were studied immunohistochemically and by transmission electron microscopy. Moreover, the number and diameter of ANP-granules in the cardiocytes were analyzed by ultrastructural morphometry. Immunohistochemically, the ANP immunoreactivity was located primarily in the perinuclear region in auricular cardiocytes of the neonatal group, but was located diffusely in the cells of the fetal group. At the 15th day of gestation, the immunoreactivity was stronger than at the 13th day of gestation. The ANP immunoreactivity observed in the cardiocytes of the newborn was weaker than in the fetal group. During the postnatal growth period, the immunoreactivity became gradually stronger. Ultrastructurally, ANP-granules in the fetal cardiocytes were scattered in the cytoplasm with immature organelles. During the postnatal growth period, the granules were predominantly located in the perinuclear region associated with the Golgi apparatus. By ultrastructural morphometry, the number of granules in the right auricular cardiocytes was significantly greater than in the left auricular cardiocytes in all groups examined. In the newborn, the number of granules was significantly less than that in the fetal group. During the postnatal growth period, the granule number of cardiocytes significantly increased. There was no significant difference between the granule number of 10-day-old neonates and of 90-day-old neonates. During the postnatal period, the granule diameter in both auricles was significantly greater than in the fetal group. The granule size was not significantly different between the right auricular cardiocytes and the left ones in all groups examined. It is suggested that a large amount of ANP-granules is secreted at the perinatal period, resulting in granule depletion in both auricular cardiocytes. more...

We tried to culture melanoma cells from a Mongolian gerbil's (Meriones unguiculatus) malignant tumor. In primary culture, most of cells have abundant melanin granules in their cytoplasm. Melanin granules decreased through 5 to 15 serial passages and disappeared after 15 th passage. The morphology of the cells varied from spindle to large polydendritic cells. Although typical melanin granules were not seen when the cells were stained by Masson-Fontana method, the cells were positive for DOPA reaction. Electron microscopically, most of the cells have well-developed Golgi apparatus and rough-surfaced endoplasmic reticulum with dilated cistern, and premelanosome-like granules were frequently observed in their cytoplasm. more...

Mouse, rat and Mongolian gerbil atrial and ventricular cardiocytes were examined by immunohistochemistry, and the right atrium including the auricle was examined by transmission electron microscopy. In addition the ANP granules of both right atrial and auricular cardiocytes were analyzed by ultrastructural morphometry. ANP immunoreactivity was detected in the atria of all three species, and the most intensely reacting cardiocytes were localized in the right auricular part of the atrium. These reactions were more prominent in the mouse and rat than in the Mongolian gerbil. ANP immunoreactivity was not detected in the ventricular myocardium of any of the three species, but was occasionally seen in the subendocardium of the ventricular septum. Ultrastructurally, the ANP granules in the auricular and atrial cardiocytes were observed to be variable in size and number, and these granules were located principally in the paranuclear region in association with the Golgi apparatus, and found throughout the sarcoplasmic layers in all three species. The ANP granules were classified into two types: A-granules containing a conspicuous electron-dense core possessing a membrane, and B-granules having profiles with a fibrillogranular, less electron-dense core than the A-granules and an indistinct membrane. The features of these granules were similar in all three species. When examined by ultrastructural morphometry, the number of each type granule and the total number of granules in the right auricular and atrial cardiocytes of the mouse and rat were significantly greater than in the Mongolian gerbil. The total number of granules in the right auricular cardiocytes was significantly greater than in the cardiocytes of the right atrium exclusive of the auricle, however, there was no significant difference between the number of A-granules and B-granules in the three species. The diameter of each type of granule in the right auricular and atrial cardiocytes of the mouse and rat was significantly greater than in the Mongolian gerbil, and the diameter of the A-granules was significantly greater than the diameter of the B-granules in all three species. more...

We studied the effects of immune sera, an antibiotic, and a corticosteroid used alone or in combination on leptospira infection in Mongolian gerbils (Meriones unguiculatus). The results suggest that the combined used of immune serum and corticosteroid (pledonizoron: PZ) inhibits the effects of serum and the marked effects of antibiotic (procaine penicillin-G: PC-G) on leptospirosis. PZ had no effects and rather shortened the survival period. PZ did not affect the effects of PC-G when used in combination. These results suggest that treatment of leptospirosis with corticosteroids requires special caution. more...

On day 13 of gestation in Mongolian gerbil fetuses, the mesonephric (Wolffian) duct was already visible. On day 14, the anlage of the paramesonephric (Mullerian) duct was first observed close to the mesonephric duct in both sexes at the cranial part of the mesonephros. Thereafter, the paramesonephric duct grew caudally in parallel with the mesonephric duct. On day 19, the duct reached the urogenital sinus. At this stage, the anogenital distance was significantly longer in male than in female. Also in male, the mesonephric duct was increased and the paramesonephric duct was decreased in diameter compared with those in female. These suggest that both testosterone and anti-Mullerian hormone are produced in fetal Mongolian gerbils at least before day 19 of gestation. more...

A cell line was established from a Mongolian gerbil's (Meriones unguiculatus) homotransplantable malignant melanoma. Ascitic tumor cells detected in a gerbil when transplanted intraperitoneally were adapted to culture. In primary culture, cells were divided into 2 types, multipolar and polygonal cells. Cell masses which adhered to polygonal cells were observed after the 6th passage. The adhering cells were removed and transferred into another flasks. The cells showed multipolar and possessed projections. Then after, the cells increased in number vigorously and formed acinous structures. At early passages, abundant melanin granules in some of the cells were demonstrated by light and electron microscopical observations. Most of the cells were positive by DOPA reaction. Melanin pigments were gradually decreased through the 20th to 30th passage and most of cells became amelanotic. The doubling time of the cell line was 32 hr. Chromosome number of the cell line ranged from 68 to 82. Whitish tumors were produced in the abdominal cavity within 30 days when intraperitoneally inoculated the cells to gerbils. This cell line, designated as MGM-A, has been subcultured for more than 100 passages during 2 years. more...

Gerbils were inoculated with reovirus type 3 (Abney strain), and the pancreas, brain and other organs histopathologically evaluated. Male Mongolian gerbils (Meriones unguiculatus) aged 5-10 days (newborn, 9 animals), 4 weeks (juvenile, 5 animals), and 12 weeks (adult, 5 animals) were used. Gerbils inoculated intraperitoneally with the virus were sacrificed 3, 5, 7, or 10 days later. Tissues were observed by light and electron microscopy. The pancreas of newborns showed inflammatory edema with infiltrates of neutrophilis and mononuclear round cells, degranulation of acinar cells and dissociation of lobules and acini with necrosis at 3 days or later after inoculation but not degeneration of pancreatic islets. Brains of newborns had necrosis of neurons and aggregation of microglial cells in the brain stem and cerebral hemisphere. Azurophilic inclusion bodies were seen in the cytoplasm of some neurons. In electron micrographs, virus particles (60-80 nm in diameter) were observed around the nucleus of neurons in the brain stem. No changes were observed in the juvenile and adult gerbils. more...

The atrial natriuretic peptide (ANP)-granules of right auricular cardiocytes were studied in aging Mongolian gerbils by immunohistochemistry and transmission electron microscopy, and analyzed by ultrastructural morphometry. Immunohistochemically, the ANP immunoreactions were weaker in 3 and 4-year-old animals than in 90-day-old, 1- and 2-year-old animals. There was no difference in the reaction among 90-day-old, 1 and 2-year-old animals, or between 3 and 4-year-old animals. Ultrastructurally, the morphological features in 1 and 2-year-old animals were similar to those of 90-day-old animals, but distinct in 3 and 4-year old animals by the presence of a few lysosomal structures in the cell. By ultrastructural morphometry, number and diameter of ANP-granules of 3 and 4-year-old animals were significantly smaller than those in the 90-day-old, 1 and 2-year-old. There was no significant difference in number and diameter among the 90-day-old, 1 and 2-year-old, or between the 3 and 4-year-old. more...

In the pig, cattle and horse, the right and left atria and ventricles were examined by immunohistochemistry, and the right atrial and auricular cardiocytes were studied by transmission electron microscopy. Moreover, ANP-granules in the cardiocytes were analyzed by ultrastructural morphometry. Immunohistochemically, the most intensely ANP-reacted cardiocytes were localized in the right auricle, particularly more prominent in the pig and cattle than in the horse. Ultrastructurally, ANP-granules were located principally in the perinuclear region associated with the Golgi apparatus and throughout the sarcoplasmic layers. They were classified into 2 types, A and B. A-granule had a conspicuous electron-dense core enveloped by a membrane. B-granule had a fibrillogranular core enveloped by an indistinct membrane. By TEM equipped with a goniometer stage, a part of the limiting membrane of B-granules became visible as the stage tilt progressed. By ultrastructural morphometry, the number of each type of granules was significantly greater in the pig and cattle than in the horse. In the pig and cattle, the total number of both types of granules in the auricular cardiocytes was significantly greater than that in the atrial ones. The diameter of each type of granules was significantly larger in the pig and cattle than in the horse. The diameter of A-granules was significantly larger than that of B-granules. more...

Mongolian gerbils, Meriones unguiculatus, were shown to be highly susceptible to Leptospira interrogans serovars such as icterohaemorrhagiae, copenhageni, canicola, autumnalis, javanica, pyrogenes and hebdomadis as compared to guinea pigs and hamsters. Mortality with signs of haemorrhage and jaundice was recorded in all experimental rodents after intraperitoneal inoculation with all strains of the serovars indicated. However, Mongolian gerbils were comparatively susceptible to strains which were of low virulence to guinea pigs and hamsters. Use of leptospiral vaccination proved effective in protecting the animals against inoculum challenges. The Mongolian gerbil is a species that may be selectively and preferentially useful for assays on the protective effects of leptospiral vaccination. more...

The atrioventricular (AV) conducting system of the heart was histologically investigated in 14 species in 9 orders of aves. The main part of the AV conducting system in aves was fundamentally similar to that in mammals, but the avian AV bundle was longer than the mammalian one and its left and right limbs had no branches crossing the ventricular cavities. In the avian heart, the accessory part of the AV conducting system was well developed. It consisted of the right AV Purkinje ring, which originated from the AV node, and the recurrent branch, which emanated from thd AV bundle. In general, the former encircled the right AV orifice and the latter encircled the aortic root, together forming an 8-shaped loop. However, the degree of development of the accessory part varied among avian species, hence allowing six types of the accessory part to be distinguished. more...

本研究の目的は, ニホンイノシシの年令と性の判定基準を作成することである. 材料として, 飼育イノシシ8例と丹波産野生イノシシ122例の頭蓋標本を用い, 歯牙の肉眼および組織学的観察をおこなった. 結果は以下の5点に要約される. 1. 歯牙の萌出と咬耗の程度によって, 12月に捕獲された89例の野生イノシシ頭蓋標本は5年令群に区分された. 2. 下顎第一後臼歯の歯根岐部の象牙およびセメント質に形成ざれる年輪によって, 上記の5年令群は7力月令およびそれに1年ずつ加算した年令に対応することが確認された. 3. 年輪を構成する広帯と薄帯のうち,後者のCa含量が高いことが認められた. 4. 年令が明らかな8例の飼育イノシシ頭蓋標本における歯牙の萌出は, 野生イノシシの歯牙の萌出と一致するものであった. 5. 解剖所見によって性別が明らかな122例の頭蓋標本を用いて性判別の基準を求めた. その結果, 下顎犬歯の冠部と頚部の計測によって, Age class II (生後19～20カ月令)以降の頭蓋標本は, 100%の的中率で性の判別が可能となった. また下顎体犬歯部のX線撮影によって, 生後6力月令の性判別ができることが明らかになった. more...

In the golden hamster (Mesocricetus auratus) the gestation period and the loculus size of the gravid uterus from day 6 to day 15.5 (parturition) of gestation as well as the weight, width (umbilcus-black) and lenght (crown-rump) of the embryos from day 9 to the parturition were measured. The results obtained were as follows: 1. The gestation period of the golden hamster was 15 days and 15 +/- 3 hours post coitum. 2. The average values of the length (in the direction of uterine long axis) and width (mesome-trial-antimesometrial axis) in the loculus of the gravid uterus were 0.39 cm and 0.56 cm at 6 days, and 2.42 cm and 1.74 cm at 15.5 days (partiurition), respectively. 3. The average values of the crown-rump measurements, width (umblicus-back) and weight in the hamster embryos were 0.42 cm, 0.24 cm and 0.026 g at 9 days, and 2.40 cm, 1.39 cm and 2.272 g at 15.5 days (parturition), respectively. 4. The loculus size of the gravid uterus, the crown-rump measurements and width (umblicus-back) of the embryos in the period from day 13 to day 14 of gestation were markedly increased in comparison with any other period, and the weight increase of the embryos occurred rapidly from day 13 of gestation. 5. The shape of the loculus during the gestation was ovoid (mesometrial-antimesometrial axis) until the end of 10 days converged to the spherical form and thereafter changed gradually to the ovoid from in the direction of uterine long axis contraly to the previous days. more...

胎仔期から出生後, 哺乳期を経て成体へと至る間の十二指腸絨毛の形態形成, 並びに絨毛吸収上皮細胞における組織学的分化の詳細を, ハムスターを材料として, 光学顕微鏡, 走査型および透過型電子顕微鏡を用いて経時的に調べた. 絨毛は胎令13.5日で初めて角柱状の絨毛として出現し, 以後胎仔期を通してその大きさ, 数は増大をみるものの角柱状の形態を保持する. 出生を境としてこの角柱状絨毛は円柱状へと移行し, 哺乳期をすぎると円柱状から成体にみられる偏平葉状の絨毛形態へと急激に近づく. 一方絨毛表面には胎令15.5日で皺襞が, また生後3日令でlarge blebsが各々初めて出現した. これら絨毛表面にみられる諸構造は日令の進行とともに発達し, 表面構造は複雑となって行く. また吸収上皮は絨毛の発現とともに, それまでの重層から単層へと移行する. 上皮細胞表面の短かく, 不規則な微絨毛は胎令の進行とともにその長さ, 密度を増し, また胎仔期に認められるグリコーゲン顆粒の集積は出生後, 急速に消失する. 出生後, 上皮細胞はその長さを増し, 核の占有面積も減少を続け, 生後10日令でほぼ成体の上皮に近い構造を獲得するに至る. また腸腺の発達や杯細胞の数の増大もこの時期まで明らかに認められる. more...

In order to clarify the relationship between three types of Indonesian native pigs (Bali, Batak of North Sumatra, and Toraja of South Sulawesi) and seven populations of Asian wild boars (Honshu, Kyushu, and Amami of Japan, Taiwan, Sumatra and Sulawesi of Indonesia, and Thai), the multivariate craniometric comparisons using 10 mandibular measurements were carried out in the present study. The results are summarized as follows: (1) Seven populations of Asian wild boars were separated into three groups by sizes: small, medium, and large, based on the discrimination by the first principal component acceptable as a size vector. The second principal component, acceptable as a shape vector, also contributed some towards the discrimination of the small-sized group from the other groups. (2) There is a complete overlapping of the principal component chart between the Batak native pigs and Toraja native pigs, both of which are short-eared. These two pigs occupy the intermediate situation between the small-sized wild boar and the medium-sized one, when they are projected into the axis of the first component. On the other hand, when they are projected into the axis of the second component, these two pigs fell in the medium-sized group of the wild boar. The Bali native pig, which is a Hainun type of the native pig, is probably to be separated both from the wild boars and from other native pigs. (3) The proportion of the ramus of the mandible to the body of the mandible seems to be an important discriminator in its shape, since the eigenvectors of measurements belonging to the ramus of the mandible show negative values, whereas those belonging to the body of the mandible show positive ones, in the second component. more...

Adrenalectomy (ADX) of pregnant rats on day 14 or 15 of gestation did not induce any hypertrophic feature in the fetal adrenals within 2 days. ADX on day 16 significantly increased both the weight of fetal adrenals and the size of fetal adrenocortical cells in 2 days. However, ADX on day 17 induced some increase in the weight of fetal adrenals, not accompanied with any significant cortical cell enlargement within 2 days. ADX on day 18 caused no increase in either the weight of fetal adrenals or the size of cortical cells. ADX on day 19 or later also induced a highly significant increase in both the weight of fetal adrenals and the size of cortical cells. To know more clearly the pattern of the negative feedback mechanism of the fetal pituitary-adrenal axis, metopirone was injected into another series of ADX rats on each of two days after ADX and the animals were autopsied on the third day. Metopirone caused more marked hypertrophy of the fetal adrenals and cortical cells than did ADX alone performed after day 16. These results strongly support the view that the fetal pituitary-adrenal negative feedback mechanism begins to operate between days 16 and 18 of gestation. more...

Ultrastructural changes of the cells forming germinal centers were examined in the chick spleen after intravenous injection of sheep red blood cells. The germinal center was formed by a cluster of large lymphoid cells and a septum of flattened reticular cells. The large lymphoid cell was characterized by numerous polysomes and a large euchromatic nucleus with a prominent nucleolus. In the developing germinal center the large lymphoid cells proliferated and became smaller in size. After the peak of development of the center they were gradually atrophied and finally became degenerative to exhibit pyknotic nuclei, condensed cytoplasm, some vacuoles and many cytoplasmic processes. From the formation of the germinal center through its degeneration, the transformation of lymphoid cells into plasma cells did not occur within the center. Plasma cells were appeared in the red pulp prior to the germinal center formation, and then they proliferated to aggregate around a periarterial lymphatic sheath. more...

The external genitalia in bovine fetuses were studied macroscopically, with special reference to the formation of the labia and the sexual differentiation. The age of fetuses was expressed in crown-rump length (CRL). The female urogenital fold budding on either side of the genital tubercle gradually approached the tip of the genital tubercle by the 33-cm stage and then began to enclose it with the companion fold on the other side, thus forming the labium pudendi which is equivalent to the labium minus pudendi of the human. The genital swellings, which are known to become the labia majora in the human, did not take part in the formation of the labia. They completely disappeared at the sites cranial to the genital tubercle by the l0-cm stage. The sex difference in differentiation of the external genitalia was first observed at the 2.7-cm stage, at which time in the male, the urogenital orifice and the anogenital raphe appeared at the sites caudal to the genital tubercle; in the female at the 2.9-cm stage, both structures were still not observable. The anogenital distance became clearly longer in male than in female, after 3.6-3.9-cm stages. more...

First, the hamster nasal turbinates were nominated as nasoturbinate, maxil-loturbinate, endoturbinates I, II, II", III and IV, and ectoturbinates 1, 2 and 3. Next, inorder to clarify the course of their development, animals from 11.0 days of gestation to149 days after birth were examined. As a result, nasoturbinate, maxilloturbinate, andendoturbinates I, II and III had already been formed by 11.0 days of gestation. Endo-turbinate II" appeared at 12.0 days, endoturbinate IV and ectoturbinate l at 12.5 days, and ectoturbinates 2 and 3 at 13.0 days. Endoturbinate IV and ectoturbinate 2 developedin the form of epithelial ridge, and ectoturbinates l and 3 in the form of subepithelialmesenchymal ridge. Endoturbinate II" was formed secondarily from endoturbinate II byseparation. Further, the course of development of each nasal turbinate was schematicallysummarized. The surface area of each nasal turbinate was measured in various growthstages. Based on these embryological findings, discussion was made on the nomenclatureof the nasal turbinates. more...

妊娠20日に母ラットの卵巣を除去後, 妊娠22日に剖検し, または妊娠20日の胎仔にβ-estradiol(0.02mg)を皮下注射し, 妊娠22日と生後1日に剖検して Leydig 細胞の総体積およびその組織像を検索したところ, estradial は出生前の Leydig 細胞の発達と出生後の萎縮に影響しなかった.

Renal juxtaglomerul;tr cell granulation in some mammals was demonstratedby Bowies staining method. Hartroft and llatrofts index was applied to different speciesin one trial. It was high in the mouse and rat, and low in the hamster. These resttlts werecorrelative with those reported by Capelli who measured the renal renin content in sonnemammalian species. In the horse, cow, sheep and guinea pig large grantnles, whiclt werestained by Bowies method, were observed near the glomerular arteriole. Then in themouse these granules were studied by electron microscope. It was observed that large cellswhich contained many heterogenous lysosomes were present in the outer layer of theepithelium of the glomerular capsttle. This observation suggested that the large granulesseen by light microscope might not be juxtaglomerular cell granules, bttt ordinarylysosomes. more...

Comparative histologic observations were made of the sinuatrial nodes of avian hearts from a short-tailed shearwater (Puffinus tenuirostris), a black-crowned night heron (Nycticorax nycticorax), two ducks (Anas platyrhycha domestica), eight Japanese quails (Coturnix coturnix Japonica), a pigeon (Columba livia domestica), a macaw (Ara macao), three budgerigars (Melopsittacus undulatus) and a jungle crow (Corvus macrorhynchos). The node lies between the right atrial myocardium and epicardium at the right caudal region of the orifice of right anterior vena cava, where the right and left sinuatrial valves come close each and fuse with the right atrial wall. The sinuatrial node is well developed in the duck, black-crowned night heron and budgerigar and enters into the both sinuatrial valves and, in the budgerigar, further into the sinus septum. In the duck and black-crowned night heron, the node is composed of two types of cells; the one is atrial muscle-like cells and the other has morphologic characteristics intermediate between atrial muscle fiber and the Purkinje fiber. The node cells of the budgerigar are of the intermediate cells, while the nodal cells in the jungle crow, macaw, short-tailed shearwater, pigeon and Japanese quail are totally atrial muscle-like cells. The nodal cells of these birds are continuous with the adjacent ordinary cardiac muscle fibers and subendocardial Purkinje fibers of the right atrium, but do not reach to the atrioventricular node. There is an extensive network of Purkinje fibers beneath the endocardium and around arteries in both atrial walls, though not as far as to the atrioventricular node, nor to the ventricle. more...

Morphological features of the vomeronasal organ in the golden hamster were examined by light and electron microscopy. This organ consisted of a 7 mm long tubular structure situated bilaterally in the anteroventral nasal septum and enclosed completely by a bony capsule. Posteriorly it ended blindly, whereas anteriorly it communicated with the nasal cavity through an orifice at its rostral end. The sensory epithelium lining the medial wall of the lumen of this organ showed a cell configuration similar to that of the olfactory epithelium except the basal cells. Free surface of the sensory cells in the sensory epithelium was covered with structures intermediate between cilia and microvilli. Capillaries often penetrated into the sensory epithelium, and the vomeronasal nerve observed under the sensory epithelium consisted of nonmyelinated nerve fibers. The respiratory epithelium lining the lateral wall of the lumen of this organ was typically ciliated and pseudostratified, devoid of goblet cells. Mucous and serous acini of Jacobson's glands were distributed on the dorsolateral and ventromedial sides of the lumen. The glands were PAS-positive, different from alcian blue-positive olfactory glands of Bowman. Myelinated and nonmyelinated nerve fibers were often distributed among the acini. more...

The heart of the duck was observed by light (LM) and scanning electron microscopy (SEM). The subendocardial Purkinje (P) fibers formed a delicate network. Most of the P fibers appeared as flattened cylinders. The end portions of these fibers showed irregular shapes. Single slender P fibers were often observed to extend from the P network into the ordinary cardiac muscle layer. more...

The proventriculus of duck is lacking in the V. proventricularis dextra and V. proventriculolienalis both of which are present in the chicken. In it the V. lienalis empties directly into the V. portae hepatis dextra. Therefore, most of the blood from the proventriculus of duck is drained by the well-developed V. proventricularis cranialis and empties into the V. cava cranialis sinistra without showing any morphological relation to the portal vein. A small amount of the remaining venous blood is drained by the portal vein after passing through the V. proventricularis sinistra; that is, most of the venous blood in the proventriculus of duck empties into the systemic circulation. In the wall of the proventriculus of duck there is a dense venous network formed by anastomosis between V. proventricularis cranialis and V. proventricularis sinistra. The systemic circulation is connected directly with the portal circulation by this anastomosis. Such a close connection between the systemic and portal circulations and the distribution of venous blood from the proventriculus appear to be a noticeable problem in birds in association with phylogenetics and food habits. Although the principle for the terminology of the venous system in the avian proventriculus was proposed by the authors, further experiments and discussion will be required for a uniformity of the nomecnlature in the future. more...

The histological development of the paracloacal vascular body was observed in the male embryo of muscovy duck. On the 14th day of incubation, the primordium of the paracloacal vascular body was first recognized as an oval mass of mesenchymal cells containing a few blood capillaries and which lay lateral to the urodeum. The well-developed blood vascular system as well as the arterioles and venules was distinguished on the 16th day. The capillary cord and the peripheral lymphatic space partly appeared on the 18th day. After this stage the peripheral lymphatic space was gradually formed around the whole parenchyma of the body, and the internal lymphatic space, the trabecula and the capsule were also developed simultaneously. All of the main components of the paracloacal vascular body thus appeared by the 24th day of incubation. On the other hand, the lymphatic space of the fibrolymphatic body occurred from the peripheral lymphatic space of the paracloacal vascular body on the 19th day. Typical reticular lymphatic spaces were formed in the fibrolymphatic body on the 24th day. more...

食虫目トガリネズミ科に属するリュウキュウジャコウネズミの腸管の形態学的特徴を体重のほぼ等しい齧歯類のマウス・ハムスターのそれらと光学顕微鏡, 走査型および透過型電子顕微鏡を用いて比較検討した. ジャコウネズミの腸管の特微として, まずその長さが非常に短かくまた盲腸の欠如している事があげられる. このため小腸と大腸の境界は不明瞭である. 絨毛は小腸ばかりでなく, 大腸に相当する部位にも存在する. これらの絨毛は齧歯類とは異なり, 表面の小皺襞は未発達で, 杯細胞の粘液放出像が多数観察される. 腸腺にパネート細胞は存在しないが, 2種類の基底顆粒細胞はしばしば観察され, 特に直腸部において多数認められる. 吸収上皮細胞の構造は他の哺乳類とほとんど同じでまた腸管各部の上皮細胞の構造にも変化は認められない. これら吸収上皮細胞間には, しばしば明調のリンパ球が散在し, 固有層には暗調の顆粒をもった特微的な細胞がリンパ球や形質細胞に混在して認められた。 more...

Pregnant rats were treated with 30 mg metopirone (M) each day for 2 days and autopsied on the third day in various gestational periods (Days 18-20, 19-21, and 20-22). Control rats were treated with saline alone (S). The adrenals of intact fetuses in M-treated dams were significantly heavier than those of intact fetuses in S-treated dams in every experimental period. In both M- and S-treated dams, the adrenals of encephalectomized (E) fetuses were lighter than those of intact littermates. However, in the experimental period of Days 18-20 and 19-21, the adrenals of E fetuses in M-treated dams were slightly but significantly heavier than those of similar E fetuses in S-treated dams. In contrast, in the experimental period Days 20-22, there was no significant difference in the weight of adrenals of E fetuses of M- and S-treated dams. These changes in fetal adrenal weight were reflected histologically in parallel changes in the size of adrenocortical cells. The observations suggest that the fetal adrenal hypertrophy following maternal treatment with metopirone can occur to some extent independent of the fetal brain, but that close to the end of gestation the hypertrophy occurs completely under the control of the fetal brain. more...

Tlae existence and the distribution of the Nymph vessels in the t?amstertestis were studied morphologically in detail. By the perfusion metlaod for fixation, theNymph vessels were observed in the interstitial tissue just adjacent to the seminiferotustubules with tire light and electron microscope.The penetrating of the Nymph vessels through the albuginea testis was confirmed andas a result of tracing these Nymph xessels, the coarse net works of the Nymph capillarieswere reconstructed and figured. The lymphatic net works were recognized to anastomoseeach other and their branches were situated just close to the seminiferous tubules and tlaeinterstitial cells. In the electronmicroscopic observation, these Nymph capillaries sltowedthe closed s)stem and so their free endings were not opened.The tissue spaces had no direct communication to the Nymph capillaries but they weresuggested to form the sinusoidal pathways of the same protein-rich liquid as that in theNymph vessels, and the important role of the interstitial tissue spaces as the passages orextracellular liquid were discussed. more...

The intercellular junction was observed in urodeal and Phallic epithelial cells of the guinea fowl, Numida meleagris, by the ultra-thin section and the freeze-fracture methods to clarify the pathway of a lymph-like fluid produced by capillaries. Only desmosomes were found between cells of the stratified squamous epithelium covering the tips of paired lateral phallic bodies. The proximal portion of the lateral phallic body and the urodeum were lined with stratified and pseudostratified columnar epithelia containing numerous mucin-secreting cells. The columnar epithelial cells were linked with junctional complexes and cytoplasmic interdigitations. Half-desmosomes connected cells of the epithelial basal stratum with the basement membrane. The zonula occludens was well developed among mucin-secreting cells, but underdeveloped among columnar epithelial cells. When these junctions were examined in freeze-fracture replicas, the zonula occludens of the mucin-secreting cell exhibited a very distinct network of branching and joining strands. This type of tight junctions appeared to serve as a barrier to prevent lymph from diffusing by the intercellular route. On the other hand, the underdeveloped zonula occludens of the columnar epithelial cell was of incomplete reticular pattern in membrane fusion. It was suggested that the lymph produced by blood and lymph capillaries might be able to pass through the epithelium to play a part in dilution of the ejaculated semen. more...

In order to clarify the normal involutionary changes in the reproductive organs and adrenals which occur as a results of hypophysectomy, a histological study on these organs of hypophysectomized female mice was performed. Twenty immature and 28 mature mice of the bc strain were subjected hypophysectomy and autopsied at various periods ranging from 1 to 150 days after hypophysectomy. the operation the immature mice were 28 to 30 days of age, and the mature ones 2 months of age. autopsy, the organs to be studied were all dissected from the surrounding fatty connective tissue, weighed and prepared for histological studies. The fixatives and staining methods employed were the same as those described in our previous reports, except for some cases in which the organs were fixed in chilled 80% alcohol and stained for alkaline monoglycerophosphatase by Gomori's technic.Following hypophysectomy there was a fall in boby weight. The reproductive organs and adrenal glands regressed in weight and underwent a pronounced atrophy. The changes in organ weights are summarized in tables 1 and 2.Ovaries: A very rapid regression in size of ovaries took place. Thus there has been a loss of some 50% in weight on the 10th day after hypophysectomy. The first structures to show significant changes after hypophysectomy were large and medium sized follicles. Signs of atresia began to be seen as early as 24 hours, showing clumping of chromatin and achromatolysis of the granulosa cells. Later the thecal cells underwent atrophy, the ovum degenerated and on the 5th day no large follicles remained. Small follicles showed a gradual decrease in number and very few were seen on the 25th day, the ovary becoming to be filled with stromal cells. However, growth of the primordial follicles did not cease. They might develop to the beginning stage of antrum formation, because in the granulosa cells of the small follicles, although not numerous, mitosis were often seen. In the ovaries of prepuberally operated mice, pituitary defficiency manifestations were also evident. Since abvanced stages of follicular maturation did not occur in any case. The most interesting fact about alkaline phosphatase which has emerged from this study is that all follicles of varying size develop large quantities of the enzyme in the granulosa layer which is normally almost devoid of activity.Ovarian stroma: The ovarian stroma of the operated mice was composed of a highly cellular tissue with densely staining nuclei. The nuclei underwent a retrogressive process designated as “wheel cell formation”.Corpora lutea: When corpora lutea were present, a process of degeneration began within 5 days and ended by the 20th day after the operation. Corpora lutea of pregnancy in the mice operated at midpregnancy, however, looked quite normal at the end of gestation.Uterus and Vagina: After the operation the uterus atrophied to a small and compact structure, very similar to that found in the spayed animals. The vaginal epithelium underwent a pronounced atrophy and the epithelium consisted of two layers of cells only.Adrenal gland: The adrenal glands underwent cortical atrophy in a marked degree and their individual cells decreased in size. The histological changes produced by hypophysectomy in the adrenal glands were almost the same as those described in our previous papers, but were somewhat prominent in females. It is of considerable interest that after operation alkaline phophatase developed in the adrenal medullary cells, which is normally devoid of activity in them. more...

THE seminal vesicles and prostates of rats are highly sensitive to androgen. In the hypophysectomized animal the recovery and growth of the regressing organs can be easily obtained by the administration of minute doses of androgen. The maintenance (Cutuly et al., 1938) or reinitiation (Nelson, 1940) of spermatogenesis and the scrotal growth, however, were not accomplished, unless animals were treated with much larger amounts of androgen. In the study of the course of sexual maturation some paradoxical facts came to attract our attention. In our colony of rats, the significant growth of the accessory sexual organs (seminal vesicles and prostates) was never observed until about 60 days of age, while spermiogenesis, descent of testis and epididymal growth began to take place almost simultaneously at the 30–40th day of age (Suzuki, 1950a,b, 1951, 1952a,b, 1954a,b.). Why do the proper accessories fail to start their significant growth at this earlier stage of the maturation process, though these organs more...

著者らはさきに('61)鶏精巣の間質内に精子が存在することを報告した.その後の研究によれば,その出現は鶏の系統と関係があるらしく考えられた.今回はその点を確かめるため,独立した15系統(3品種),184羽の材料について検査して,次のような結果をえた.1. 間質内に精子を認めうる場合には,多くは単独でなく,数個ないし十数個の集団をなして存在する(+)が,尾部の構造を確認できるものは少数であつた.連続切片で精査しても,単独精子のみの場合もあつた(±).2. 単独,集団いずれの場合も,多くは同一の切片中数ヵ所以上で認めることができた.3. +,±を合せれば,15系統中4系統で認められ,品種的には殆んどが白色レグホーン(W.L.)で,ニューハンプシャー(N.H.)で1例が認められたにすぎない.4. 出現例数は,+はW.L.で6例(3系統),N.H．で1例の計7例,±はW.L. 1系統で4例がみられた.出現率:+は3.80%,±は2.17%,両者を合せると5.98%であつたが,系統別にみると,+はE種鶏場B,C系でそれぞれ19.05,4.76%を示し,1種鶏場A系では14.29%,T牧場では6.66%であり,±は19,05%(E-B系)であつた.E種鶏場B系では+,±を合せると38.09%の高率を示した.5. 日令的には,+,±いずれも殆んどが7カ月令にみられ,1力年令で2例,2～3年令鶏では皆無であつた.2～3年令鶏は少数であるから,出現と日令の関係は確言はできない.6. 本現象と品種間には特殊な関係はないように考えられる.7. 本現象の最も多くみられたE種鶏場の系統の授精率は80%以上であつた.従つて授精率を極端に低下させるものではないであろう.その他の生理的意義も不明である.8. 間質内精子の成因について,2～3の可能性が考えられたが,やはり疑問は残された. more...

1 マウス副腎皮質X-zone細胞の細胞質は明かに好塩基性を示し,この好塩基性はリボ核酸に依るものである事を確めた。2 本層細胞内のRNAの分布型は多様である。又細胞質内のRNAの量はオスミウム還元物質と量的に逆の関係を示す様である。3 幼若及び去勢雄マウスのX-zoneにエオジン,フクシン好性を示すコロイド様物質が認められ,その一部はRNAを僅かに含んでいた。4 X-zone中には多数の有糸分裂像が認められ,退化像は比較的少く,退化細胞の細胞質にはRNAの消失が認められ,核は核融解に係る退化像を示すものが殆どを占めPycnosis様の変化を認めなかつた。5 X-zone細胞の細胞質中にRNAの存在することから本層が常に何等かの機能に関与していると考えられ,此の点に就て論じた。擱筆するに当り終始変らざる御指導を仰いだ恩師増井清博士並に幾多の御便宜を頂いた市川収博士に衷心より感謝の意を表する次第である。尚本研究は文部省科学研究費に依る研究の一部である。 more...