Morphology of the dorsal lingual papillae in the Japanese macaque and Savanna monkey.

The dorsal lingual surfaces of infant Japanese macaque (Macaca fuscata) and adult savanna monkey (Cercopithecus aethiopus) were examined by scanning electron microscopy. Filiform, fungiform, foliate and vallate papillae were found. The filiform papillae were distributed over the entire dorsal surface of the tongue. The fungiform papillae were round in shape, and more densely distributed on the lingual apex. The foliate papillae were seen on the dorsolateral aspect of the tongue. The three vallate papillae were arranged like a triangle with the apex of the triangle directing caudally. Each papilla was surrounded by a groove. The rudiments of the fungiform, foliate and vallate papillae were visible earlier than those of the filiform papillae.

Effect of low or high dietary calcium on the morphology of the rat femur.

The present study compared the effect of a calcium deficit or surfeit on femurs. Young female rats were fed with the normal (1.18%), low (0.05%), or high (2.00%) calcium diet for 3, 7, 15 or 30 days. Two groups received the low calcium diet for the first 15 days and then were followed by the normal (L-N) or high calcium diets (L-H) for the sequential 15 days. The morphology of the femur was studied together with serum calcium, parathyroid hormone (PTH), calcitonin and bone mineral density (BMD). We did not find any significant changes in the serum PTH level and bone morphology in the high calcium group. In the low calcium group, the serum PTH level increased, BMD of the whole body, the femoral weight and the femoral trabecular bone decreased as compared with the normal calcium group. There was a greater proportion of resorbing surface, less resting surface and larger vascular canal openings in the femoral endosteal surfaces in the low calcium group. In the L-N or L-H group, the femoral trabecular bone increased and the femoral resorbing surface decreased as compared with those of the low calcium group. These findings suggest that high calcium intakes do not affect the bone mass, and low calcium intakes have a deleterious effect on bone status, which may be related to vascular alternations of the bone. Reversing the low income calcium intake by a higher calcium diet can partially improve the bone alternations induced by low calcium intake.

Effects of cigarette smoke exposure on the ultrastructure of the golden hamster parathyroid gland.

Cigarette smoking has been identified as one of the risk factors to induce osteoporosis. However, we find no study on the morphology of the parathyroid gland under smoking exposure. We studied the ultrastructure of the parathyroid gland, lung and femur of the golden hamster exposed to cigarette smoke. Four-week-old male hamsters were housed in a plastic case (48x31x30 cm) and were exposed to cigarette smoke for 12 weeks, 5 minutes exposure, 4 times a day, 4 days a week. There were no differences in serum calcium level and the whole bone mineral density between the control and the smoke-exposed groups. In the parathyroid gland of the smoke-exposed animals, the Golgi complexes associated with many prosecretory granules were well developed and many secretory granules were located near the plasma membrane. Large lipid-like inclusion bodies were observed in the alveolar macrophages of the smoke-exposed animals. The femur morphology showed a wider area of resorbing surface in the smoke-exposed group than in the control group. From these findings, it is conceivable that the secretory activity of the parathyroid gland was stimulated with cigarette smoke exposure.

Effects of ethanol on the ultrastructure of the hamster femur.

Several previous studies have indicated that chronic ingestion of ethanol exerts harmful effects on bones. However, few data are available concerning the effects of ethanol on the ultrastructure of bone. To further elucidate the effects of ethanol on bone, we studied the morphology of femur in golden hamsters after long-term treatment with ethanol. Six-week-old male hamsters were divided into 4 groups. Ethanol-treated animals were given ethanol at a concentration of 7% with food and water freely available, whereas the pair-fed animals (weight-matched to ethanol hamsters) had tap water available as the only drinking fluid. The femur weight, blood ethanol and serum calcium concentrations were determined after 3 and 5 months. The bone mineral density (BMD) of the whole body was measured before and after the experiment. Femurs of both sides were dissected and processed for morphometric measurement, light microscopy, scanning and transmission electron microscopy. In the ethanol-treated hamsters, BMD of the whole body and the weight of femur tended to decrease when compared with those of the controls. Light microscopy and scanning electron microscopy showed that the trabecula in the distal end of the femur from ethanol-treated hamsters were thinner than those of the controls. We also observed the disrupted swollen mitochondria of the femoral osteoblasts and osteocytes in the ethanol-treated hamsters. No significant difference in serum calcium levels and femoral osteoclasts was found. These results indicate that long-term treatment with ethanol results in disruption of femoral osteoblasts and reduction of bone mass in trabecular bone.

Morphological identification of the lipid-storing cells in golden hamster parathyroid glands after vitamin A treatment.

We investigated hamster parathyroid glands of different ages using electron microscopy and found a new cell type in young, adult and senile hamsters. Theses special cells were located in interstitial tissues and invariably contained several lipid droplets within the cytoplasm. The cells showed an elongated spindle with some cell processes. The cells contained small Golgi complexes and moderate cisternae of the granular endoplasmic reticulum. The morphological characteristics of these cells were mostly the same as those of lipid-storing cells in other organs (Yamada and Hirosawa, 1976). After vitamin A administration, the lipid droplets in these cells markedly increased in number and also in volume density. The other morphological features of these cells resembled those of the control animals. We called these cells parathyroid lipid-storing cells. They may incorporate and store vitamin A within the lipid droplets. They can be classified as one of the cellular components in hamster parathyroid gland.

[SEM study on the dorsal lingual surface of the nutria, Myocastor coypus].

The dorsal lingual surface of prenatal and postnatal nutria was examined by scanning electron microscopy (SEM). Filiform (Fi), fungiform (Fu), foliate (Fo) and vallate papillae (Va) were observed. The Fi differed in morphology by their location on the tongue and could be classified into 3 types: 1) conical, 2) long, and 3) short filiform papillae. The Fu were scattered among the Fi. Many Fo were observed on the posterolateral regions of the tongue. There were 2 Va separating the anterior 2/3 from the posterior 1/3 of the tongue. The rudiments of Fu, Fo and Va were visible earlier than those of the Fi.

SEM study on the dorsal lingual surface of the lesser dog-faced fruit bat, Cynopterus brachyotis.

The dorsal lingual surface of the lesser dog-faced fruit bat was examined by scanning electron microscopy (SEM). Filiform (Fi), fungiform (Fu) and vallate papillae (V) were observed. The Fi papillae were distributed over the entire dorsal surface of the tongue. The Fi papillae notably differed in morphology by their location on the tongue and could be classified into 5 types: 1) crown-like papillae, 2) giant trifid papillae, 3) scale-like papillae, 4) small conical papillae, and 5) large conical papillae. The Fu papillae were present rounded bodies on the anterior 2/3 of the tongue. The lesser dog-faced fruit bat showed the triangular arrangement of the three V, with the apex of the triangle directed posteriorly.

A case of left inferior vena cava.

A case of left inferior vena cava (IVC) was found in a 72-year-old male cadaver during student dissection practice in 1999 at Gifu University School of Medicine. It was formed by junction of the left and right common iliac veins at the lower left corner of the 5th lumbar vertebra. This IVC (15-mm caliber) ascended 82 mm along the left side of the abdominal aorta dorsally to the ureter. Receiving the left renal vein, it became 21 mm in caliber and ran obliquely upward for 43 mm across the abdominal aorta. As soon as it received two right renal veins at the level of the 2nd lumbar vertebra, the IVC (25-mm caliber) turned directly above. The present case belongs to Type C of the classification of McClure and Butler (1925), which is based on the combinations of the left and right IVCs, and on their location relative to the ureters. The present case also belongs to Type 1 of the classification of Yoshida et al. (1981). We consider that left IVC in the present case is mainly caused by disappearance of the right supracardinal vein and persistence of the left one during the embryological development of the IVC.

Effect of low calcium diet on the ultrastructure of the rat parathyroid gland.

Young female rats were fed with normal (1.18%) or low (0.05%) calcium diet for 3, 7, 15 or 30 days. The morphology of the parathyroid glands was studied together with serum calcium, parathyroid hormone (PTH), calcitonin and bone mineral density (BMD). As compared to the animals fed with the normal calcium diet, BMD of whole body of the rats fed with the low calcium diet was significantly decreased, whereas the serum PTH level was increased. The parathyroid glands in the rats fed with the low calcium diet were markedly enlarged. In the parathyroid chief cells of the rats fed with the low calcium diet, the Golgi complexes and the cisternae of the granular endoplasmic reticulum were well developed, while the large granules and large vacuolar bodies decreased. Some secretory granules located near the plasma membrane. A proportionally larger increase of the cytoplasm was estimated in the rats fed with the low calcium diet for three and seven days. Enlargement of the cytoplasm and rather frequent mitoses of the chief cells were observed in the rats fed with the low calcium diet for 15 and 30 days. These findings suggest that the rapid bone loss in young rats induced by the low calcium diet is essentially due to stimulated activity of the parathyroid gland. The stimulated gland may be a result of hypertrophy at the early stage and a combination of hypertrophy and hyperplasia at the later stage of calcium deficiency.

A case of the horseshoe kidney.

During cadaver dissection for student education in anatomy laboratory of Gifu University School of Medicine, a case of the horseshoe kidney was observed in a 63-year-old Japanese female cadaver. The kidney was fused at the lower poles of the original kidneys by the parenchymatous isthmus and showed a typical horseshoe shape. The hili on both sides opened towards the ventral direction, and the ureters descended in front of the isthmus and entered the bladder normally. The location of the kidney was lower than that of the normal kidney. Four surplus arteries entered the isthmus and the lower part of the kidney besides the normal right and left renal arteries. The incidence of the horseshoe kidney during the dissecting practice at Gifu University School of Medicine from 1971 to 1997 was estimated to be 0.36% (4 out of 1130 bodies).

Morphology of the dorsal lingual papillae in the newborn panther and Asian black bear.

The dorsal lingual surfaces of a newborn panther (Panthera pardus) and two newborn asian black bears (Selenarctos thibetanus) were examined by scanning electron microscopy (SEM). The tongues of the panther and asian black bear were about 40 mm in length and about 20 mm in width. Filiform, fungiform and vallate papillae were found. The filiform papillae were distributed over the entire dorsal surface of the tongue. In the panther, the filiform papillae on margin of the lingual apex were divided into two shapes which were horny or club-shaped papillae. The filiform papillae on the midportion were larger than those on the lateral region in size. The fungiform papillae also were divided into two shapes which were hemispherical or club-shaped papillae. In the asian black bear, the filiform papillae on the margin of the lingual apex were larger than those on margin of the panther tongue. The vallate papillae in the animals of two species were located on both sides of the posterior end of the lingual body. Each papilla was surrounded by a groove and crescent pad.

Occurrence of the parathyroid cyst in golden hamsters.

Parathyroid cyst is a rare lesion, but has clinical significance because of it's ability to mimic a thyroid mass and it's association with hyperparathyroidism. The occurrence and morphology of parathyroid cysts in golden hamsters from neonatal to senile periods were investigated using light and electron microscopy. The results demonstrate the presence of chief cell cysts in the parathyroid glands of 5-day-old hamsters. Some chief cells lining the cyst wall showed mitosis and apoptosis. The existence of chief cell cysts may represent the rapid proliferation of the parathyroid chief cells in 5-day-old hamsters. Ciliated cysts were observed in the parathyroid glands of 5-day-, 1- and 3-month-old hamsters. Three cell types were distinguished in the wall of the ciliated cyst: Ciliated, mucous and basal cells. Ciliated cysts possessed the features of the pharyngeal epithelia without endocrine cells and may arise from embryological remnants of pharyngeal pouches in the neck undergoing cystic degeneration and entrapping portions of parathyroid tissue. The frequency of parathyroid cysts decreased with age.

Two cases of the double inferior venae cavae.

Two cases of the double inferior venae cavae (IVC) were found during the student dissection practice in 1997 in Gifu University School of Medicine. On the first case (70-year-old male), the calibers of the right and left IVC were 15 mm and 13 mm, respectively. An anastomosis (4-mm caliber) ran obliquely from the left internal iliac vein to the right IVC. On the second case (86-year-old male), the calibers of the right and left IVC were 15 mm and 10 mm, respectively. We found no anastomosis between the right and left IVC. Each IVC was observed behind the ureter. Both cases belong to Type BC of the classification of McClure and Butler (1925), that is based on the combinations of the right and left IVC, and on their location to the ureters. Both cases also belong to Type II-b-2 of the classification of Takemoto et al. (1978), that is based on the calibers of the right and left IVC and on the running course of the interiliac vein. These are the first and second cases among 808 cadavers in Gifu University School of Medicine and the 93rd and 94th cases in Japan since 1901.

Morphology of the dorsal lingual papillae in the barbary sheep, Ammotragus lervia.

The dorsal lingual surface of a barbary sheep (Ammotragus lervia) was examined by scanning electron microscopy (SEM). The tongue was about 20 cm in length. There were about 30 vallate papillae on both sides. Filiform, conical, fungiform and vallate papillae were found. The filiform papillae were distributed over the entire dorsal surface of the tongue, excepted for the lingual torus where conical papillae were present. The fungiform papillae were present rounded bodies, and more densely distributed as compared to that of the lingual body on the tip and ventral surface of lingual apex. No foliate papillae were seen on the dorsal surface. The vallate papillae were located on both sides of the midline in the caudal part. Each papilla was surrounded by a groove. These findings indicate that the tongue of the barbary sheep is similar to that of the formosan serow, japanese serow and blackbuck.

Acute effects of caffeine administration on the ultrastructure of the golden hamster parathyroid gland.

This study was conducted to evaluate the acute effects of caffeine on the ultrastructure of the parathyroid glands in golden hamsters. Caffeine was given orally at either 2.5 mg (low dose) or 10 mg (high dose) per 100 g body weight. Caffeine caused a dose dependent decrease of the serum calcium level 2 hours after administration. Transmission electron microscopy of the parathyroid gland revealed that the volume densities occupied by the Golgi complexes and rough endoplasmic reticulum (RER) were found significantly higher 2 hours after receiving high dose of caffeine. Statistical analysis revealed no significant differences regarding to the bone mineral content (BMC) and bone mineral density (BMD). It is considered that the synthesis of parathyroid hormone is stimulated following caffeine administration.

Effects of long-term treatment with caffeine on the ultrastructure of the golden hamster parathyroid gland and tibia.

The ultrastructure of the parathyroid gland and the SEM appearances of the tibia were studied in hamsters with and without administration of caffeine. Caffeine was treated orally each day at either 2.5 mg (low dose) or 10 mg (high dose) per 100 g body weight for a period of 17 or 32 days. Statistical analysis showed no significant differences among all groups examined regarding the serum calcium level. Transmission electron microscopy of the parathyroid gland revealed that the volume densities occupied by the mitochondria, Golgi complexes and rough endoplasmic reticulum of caffeine-treated groups were found significantly higher when compared with controls. The number of secretory granules observed close to the cell membrane per total amount of these granules revealed significant increase in all caffeine-treated animals. The bone mineral content (BMC) values were closely related to body weight. In the high dose caffeine-treated hamsters increment of the mean BMC and body weight values was significantly lower than those of the controls after 32 days. In the scanning electron microscopic studies of the tibia, no alteration in the morphometric parameters was demonstrated. It is considered that the synthesis and release of parathyroid hormone is stimulated following caffeine consumption. Our data suggest that although chronic administration of caffeine in the hamster may slightly increase bone turnover as evidenced by the BMC decrease, bone morphometry was not altered. Thus the osteoporotic changes were not proved in this study.

Effects of ethanol on the ultrastructure of the hamster thyroid C-cell.

The morphology of the thyroid C-cells in golden hamsters after short- and long-term treatment with ethanol was studied. Immunohistochemistry was applied to examine the distribution of the C-cells in the thyroid gland. In the short-term experimental animals, the Golgi complexes and the granular endoplasmic reticulum were well developed and the number of the secretory granules was decreased as compared with those of the control animals. These findings suggest that the cellular activity of the thyroid C-cell is stimulated after short-term treatment with ethanol. The morphology of the thyroid C-cells of the long-term experimental animals was similar to that of the controls. It is conceivable that long-term treatment with ethanol does not affect the function of the C-cell.

Morphology of the dorsal lingual papillae in the bush dog (Speothos venaticus).

The dorsal lingual surface of a bush dog (Speothos venaticus) was examined by scanning electron microscopy (SEM). The tongue was about 7 cm in length. Filiform, fungiform and vallate papillae were found. The filiform papillae were distributed over the entire dorsal surface of the tongue. Each filiform papillae on the apical surface of the tongue had several conical processes, in the midportion were larger than those on the apex in size. In the region of the vallate papillae, the filiform papillae had not the conical processes and more larger than those on the midportion of the tongue. The fungiform papillae were present rounded bodies and more densely distributed on the tip of the lingual apex. There were 5 vallate papillae on both sides. The vallate papillae were located on both sides of the posterior end of the lingual body. Each papilla was surrounded by a groove and a crescent pad. In the dorsal surfaces of the papillae, small conical papillae were observed.

Morphology of the dorsal lingual papillae in the black rhinoceros (Diceros bicornis).

The dorsal lingual surface of a black rhinoceros (Diceros bicornis) was examined by scanning electron microscopy. The tongue was about 30 cm in length. There were about 60 vallate papillae on both sides. Filiform, fungiform and vallate papillae were found. The filiform papillae were distributed over the entire dorsal surface of the tongue. The papillae had a hair-like shape. The fungiform papillae were round in shape, and more densely distributed on the lingual apex. No foliate papillae were seen on the dorsal surface. The vallate papillae were located on both sides of the posterior end of the lingual body. Each papilla was surrounded by a groove.

SEM study on the dorsal lingual surface of Microtus montebelli.

The dorsal lingual surface of Microtus montebelli was examined by scanning electron microscopy (SEM). The filiform papillae were distributed over the entire dorsal surface of the tongue. The filiform papillae notably differed in morphology by their location on the tongue and could be classified into 4 types: 1) simple conical papillae, 2) true filiform papillae, 3) giant conical papillae, and 4) saw-like papillae. The fugiform papillae were present rounded bodies scattered over the anterior dorsal surface of the tongue. A vallate papilla was located at the middle end of the lingual body. The surface of the radix zone was smooth and without lingual papillae.