As recently as 1972 research on the submandibular duct reservoir was reported by Butcher (1972) using Long-Evans and wristar rats. The occurrence of the submandibular duct reservoir in other species of rodents has not been determined. The author has attempted to observe the occurrence of the submandibular duct reservoir in adult albino rats of the Sprague-Dawley strain as well as in mice and rabbits and to observe the morphodifferentiation of the submandibular gland, especially the submandibular duct reservoir in the rats. The whole submandibular and sublingual ducts associated with the glands and the sublingual caruncle were carefully excised under a stereomicroscope after perfusing the animal with 10% formalin solution. The submandibular and sublingual complexes were, in toto, post-fixed in Zenker's solution for 24 hours and sectioned serially. To observe the prenatal phase of the morphogenesis of the submandibular gland, serial sections of the head and neck at daily intervals from 14 days to 20 days in utero, were all fixed using Bouin's solution. The results have shown that in the serial sections of the glandular complexes of the adult rats, a diverticular enlargement of the submandibular duct near the sulbingual caruncle existed and was connected to the ordinary narrow excretory duct distal to the diverticular enlargement of the submandibular duct. The submandibular duct reservoir followed by the short terminal excretory duct opened into the oral cavity through the sublingual caruncle. The lining epithelium of the diverticular enlargement of the submandibular duct was the pseudostratified columnar type. No sublingual duct reservoir was found in the Sprague-Dawley strain rats that were investigated. In the mouse and the rabbit there was no submandibular duct reservoir found. The anlage of the submandibular gland was first observed in the 14 day old in utero specimens. In the 17 dey old in utero specimens, an apparent submandibular duct reservoir was present and the terminal buds (anlage of acini) were well differentiated. Secretory materials were seen in the lumina of the submandibular duct and in the terminal buds. These findings indicate that the secretion of the submandibular gland cannot enter the oral cavity until at least 16 days in utero.
Animal ; Mice ; Rabbits ; Rats/anatomy & histology* ; Submandibular Gland/anatomy & histology*

Poison the rats by pesticide Bassa with dose 205mg/kg of their body mass. Observe the changes morphological and chemical structure of rats liver, remark: The changes in the liver were clearly show on the thirdly days, find expression: disorder circulation of the blood, degradation cytoplasma of hepatocytes, number hepatocytes with 2 nuclei diminished, decreased in quantities glycogen, increased in the number lipid. After the third day, regeneration of the liver rapidly happened
Poisoning ; Rats ; anatomy & histology ; chemistry ; liver ;

AIMTo isolate and purify the brain microvessels without intact neural cells used for cloning specific gene at the blood-brain-barrier.

METHODSMagnetic beads ranging from 200-500 nm were synthesized and infused into cerebral spheres through carotid arteries. The brain tissues were dissected by mechanic and enzymatic methods, and sieved to discharge tissues and large blood vessels. The brain microvessels labelled by magnetic beads were sorted in magnetic fields, and identified by morphology, molecular biology and biologic activity.

RESULTSScanning electric micrograph of the obtained brain microvessels showed the vessels grossly free of adjoining neural cells except an occasional nerve ending. RT-PCR products of microtube-associated protein 2a, glutamine synthetase and CD31 from brain tissue had positive lanes, but only CD31 had positive lanes from isolated microvessels. The endothelial cells from isolated microvessels had more fluorescence than that from cultured endothelial cells.

CONCLUSIONHighly purified microvessels without intact neural cells can be obtained by this method.

Animals ; Blood-Brain Barrier ; anatomy & histology ; Brain ; blood supply ; Microvessels ; anatomy & histology ; Rats

Interpositionally grafted arteries and veins were expanded with a 20cc tissue expanders in 50 Sprague-Dawley rats. The grafts were done on both hind legs, one side was expanded and the remaining side was used as control. The average gain in length of expanded grafted arteries and veins was over 4 and 6 times that of the controls respectively. The differences in the patency rates between expanded and control grafts were not statistically significant. Histologic examination revealed that there were no changes in the areas of the media and lengths of the inner elastic laminae of the expanded arterial grafts. In both expanded and control vein grafts, marked intimal thickening was noticed, although these changes were not statistically significant. Expansion of grafted vessels can be safely carried out without loss of vessel patency. Tissue expander, grafted vessels
Animal ; Femoral Artery/*anatomy and histology/transplantation ; Male ; Rats ; Rats, Inbred Strains ; *Tissue Expanders ; Vascular Patency ; Veins/*anatomy and histology/transplantation

Interpositionally grafted arteries and veins were expanded with a 20cc tissue expanders in 50 Sprague-Dawley rats. The grafts were done on both hind legs, one side was expanded and the remaining side was used as control. The average gain in length of expanded grafted arteries and veins was over 4 and 6 times that of the controls respectively. The differences in the patency rates between expanded and control grafts were not statistically significant. Histologic examination revealed that there were no changes in the areas of the media and lengths of the inner elastic laminae of the expanded arterial grafts. In both expanded and control vein grafts, marked intimal thickening was noticed, although these changes were not statistically significant. Expansion of grafted vessels can be safely carried out without loss of vessel patency. Tissue expander, grafted vessels
Animal ; Femoral Artery/*anatomy and histology/transplantation ; Male ; Rats ; Rats, Inbred Strains ; *Tissue Expanders ; Vascular Patency ; Veins/*anatomy and histology/transplantation

Afferent Pathways ; anatomy & histology ; Animals ; Female ; Ganglia, Spinal ; anatomy & histology ; Neurons, Afferent ; Rats ; Rats, Sprague-Dawley ; Urinary Bladder ; innervation

BACKGROUNDThe morphological measurements of seminiferous tubules are important in the studies of testis tissues. The purpose of this study was to evaluate the feasibility of using a stereological method to measure the geometric parameters of seminiferous tubule and to optimize the method.

METHODSA stereological image processing program was developed with Delphi for the stereological measurement. Fields of view were obtained from 15 healthy Wistar rats' testis tissues (n = 247). The diameter, area and volume of seminiferous tubule were estimated with the image processing program by two individual observers. The area results were compared with those obtained by the standard morphometric method of planimetry.

RESULTSDiameter measurements showed the diameters of different seminiferous tubules were almost the same and the mean value of about 50 tubules could be a good representation of the whole structure. Area measurements indicated there was no significant difference between stereology and planimetry (P > 0.05). But the stereological method required about 45% less time. Volume measurement showed the inter-observer variability was small (P > 0.05) and the reproducibility of the stereological method was good.

CONCLUSIONThe stereological technique was practical and efficient in the quantitative measurement of the rat's seminiferous tubule.

Animals ; Image Processing, Computer-Assisted ; methods ; Male ; Rats ; Rats, Wistar ; Seminiferous Tubules ; anatomy & histology ; Testis ; anatomy & histology

OBJECTIVEDivision of the CA1, CA3 and dentate gyrus (DG) regions of the hippocampus of Wistar rat under the stereomicroscope.

METHODSTwenty-four Wistar rats were randomly assigned to three groups. (1) The brain was sectioned coronally (n = 6). The sections were stained with thionin and the morphology of cells in each region of the hippocampus was observed under microscopy. (2) The hippocampus was dissected out and observed on the whole. Then, the CA1, CA3 and DG regions of the hippocampus were divided. Every region divided was sectioned, and the morphology of cells was observed. (3) Rats with brain ischemia or not were also decapitated and the HSP 70 expressions were observed in CA1, CA3 + DG regions by Western blot and immunohistochemical staining (n = 12).

RESULTS(1) The CA1, CA3 and DG regions of the hippocampus could be clearly observed in coronal section of the brain stained by thionin. (2) Under the stereomicroscope, the CA1 and DG regions of the hippocampus could be separated along the hippocampal fissure between them in ventral surface of the hippocampus. The CA3 and DG regions of the hippocampus could be separated along a fissure between them. The appearance of cells in the sections of the divided CA1, CA3 and DG specimens is consistent with that in the brain coronal sections, respectively. (3) The results of Western blot indicated that the HSP 70 expression of the brain ischemia group was up-regulated significantly in CA3 + DG regions compared with the sham group. However, HSP 70 expression has no significant changes in CA1 region. The above results were consistent with those of the immunohistochemical staining.

CONCLUSIONThe CA1, CA3 and DG regions of the hippocampus of Wistar rat could be divided under stereomicroscope, and the divided each region was sensible for detection of protein using Western blot.

Animals ; CA1 Region, Hippocampal ; anatomy & histology ; metabolism ; CA3 Region, Hippocampal ; anatomy & histology ; metabolism ; Dentate Gyrus ; anatomy & histology ; metabolism ; Male ; Rats ; Rats, Wistar

The purpose of this study was to evaluate whether the cranial and circumaxillary sutures react differently to maxillary expansion (ME) and alternate maxillary expansions and constrictions (Alt-MEC) in a rat model. Twenty-two male Sprague-Dawley rats (6 weeks old) were used and divided into three groups. In ME group (n=9), an expander was activated for 5 days. In Alt-MEC group (9 animals), an alternate expansion and constriction protocol (5-day expansion and 5-day constriction for one cycle) was conducted for 2.5 cycles (25 days total). The control group comprised 4 animals with no appliances used, each of two sacrificed on day 5 and day 25 respectively. Midpalatal suture expansion or constriction levels were assessed qualitatively and quantitatively by bite-wing X-rays and cast models. Distances between two central incisors and two maxillary first molars were measured on cast models after each activation. Circumaxillary sutures (midpalatal, maxillopalatine, premaxillary, zygomaticotemporal and frontonasal suture) in each group were characterized histologically. Results showed that midpalatal suture was widened and restored after each expansion and constriction. At the end of activation, the widths between both central incisors and first molars in Alt-MEC group were significantly larger than those in ME group (P<0.05). Histologically, all five circumaxillary sutures studied were widened in multiple zones in Alt-MEC group. However, only midpalatal suture was expanded with cellular fibrous tissue filling in ME group. Significant osteoclast hyperplasia was observed in all circumaxillary sutures after alternate expansions and constrictions, but osteoclast count increase was only observed in midpalatal suture in ME group. These results suggested that cranial and circumaxillary sutures were actively reconstructed after Alt-MEC, while only midpalatal suture had active reaction after ME.
Animals ; Male ; Mandible ; anatomy & histology ; physiology ; Masticatory Muscles ; anatomy & histology ; physiology ; Maxilla ; anatomy & histology ; physiology ; Range of Motion, Articular ; physiology ; Rats ; Rats, Sprague-Dawley

The occurrence of the submandibular duct reservoir was reported by Butcher (1972). Its form and functional volume (Schneyer, 1975) and the development of the submandibular complex (Kim, 1975) were studied. The shape of the cells in the epithelial lining of the reservoir had not been determined as yet. So via the techniques of histology and histochemical enzymatic activity, the epithelial lining and the function of the reservoir were investigated. The epithelial lining of the reservoir was not uniform in all regions. The proximal portion of the reservoir was lined by pseudostratified columnar epithelium and the distal portion was lined by stratified columnar or cuboidal epithelium. Acid phosphatase activity in the epithelial lining of the reservoir was observed as well as in the acini, granular convoluted duct and striated duct of the submandibular gland proper.
Acid Phosphatase/metabolism ; Animal ; Epithelial Cells ; Epithelium/enzymology ; Rats/anatomy & histology* ; Submandibular Gland/anatomy & histology* ; Submandibular Gland/cytology