Review article
- Synovial
membrane in the temporomandibular joint - Its morphology, function and development
(NOZAWA-INOUE, K.)
Original articles
- Immunolocalization
of the water channel, aquaporin-5 (AQP5), in the rat digestive system (MATSUZAKI,
T.)
- Origins
and pathways of fluid entering sublobular lymphatic vessels in cat livers (POONKHUM,
R.)
- Ontogeny of
plasma cells in the early rat yolk sac (EL-NEFIAWY, N.)
- Expression
of gastrin-releasing peptide (GRP) in the bovine uterus during the estrous cycle
(BUNDIPITOJO, T.)
- The
expression of pancreatic endocrine markers in centroacinar cells of the normal
and regenerating rat pancreas: their possible transformation to endocrine cells
(SUZUKI, T.)
- Tyramide
signal amplification enhances the detectable distribution of connexin-43 positive
gap junctions across the ventricular wall of the rabbit heart (MCLACHLAN, CS.)
- Purification,
cDNA cloning, and secretory properties of FLRG protein from PC12 cells and the
distribution of FLRG mRNA and protein in rat tissues (OHSAWA, Y.)
Summary
Title
Synovial membrane in the temporomandibular joint-Its morphology,
function and development
Author
Kayoko Nozawa-Inoue, Norio Amizuka, Nobuyuki Ikeda, Akiko Suzuki, Yoshiro Kawano,
and Takeyasu Maeda
Address
Division of Oral Anatomy, Department of Oral Biological Science, Niigata University
Graduate School of Medical and Dental Sciences, and Center for Transdisciplinary
Research, Niigata University, Niigata, Japan
Summary
This paper reviews recent findings of the synovial membrane, in particular the
morphology, function and development of synovial lining cells, in the temporomandibular
joint (TMJ). Electron microscopic studies have confirmed the synovial membrane
in TMJ consists of macrophage-like type A cells and fibroblast-like type B cells
identical to those in other systematic joints. The macrophage-like type A cells
react with anti-macrophage and macrophage-derived substances including the major
histocompatibility class II molecule, and show a drastic increase in their number
in the inflamed synovial membrane. In addition, they have the ability to produce
substances involved in the progression of TMJ inflammation such as nitric oxide
and inducible nitric oxide synthase. Observation of osteopetrotic mice revealed
that macro-phage-like type A cells in TMJ are derived from monocyte lineage. Immunocytochemistry
for 25kDa heat shock protein was able to depict the entire shape of fibro-blast-like
type B cells including their unique processes. The expression of an estrogen receptor
α-immunoreaction in the fibroblast-like type B cells may explain the etiology of
temporomandibular disorders at a higher frequency in fe-males than in males, suggesting
that TMJ is a target tissue for estrogen. Furthermore, fibroblast-like type B
cells are equipped with a basement membrane to serve as an adhesion molecule for
the fibroblast-like type B cells to keep their epithelial arrangement. A clear
understanding of the morphology of the intact synovial membrane will serve to
clarify the etiology and development of temporomandibular disorders.
Correspondence: Kayoko Nozawa-Inoue, DDS, PhD, Division of Oral Anatomy, Department
of Oral Biological Science, Niigata University Graduate School of Medical and
Dental Sciences, 2-5274 Gakkocho-dori, Niigata 951-8514 Japan
Tel: +81-25-227-2818, Fax: +81-25-223-6499
E-mail: nozawa@dent.niigata-u.ac.jp
Title
Immunolocalization of the water channel, aquaporin-5 (AQP5),
in the rat digestive system
Author
Toshiyuki Matsuzaki, Yuki Tajika, Takeshi Suzuki, Takeo Aoki, Haruo Hagiwara,
and Kuniaki Takata
Address
Department of Anatomy and Cell Biology, Gunma University Graduate School of Medicine,
Maebashi, Japan
Summary
Aquaporin-5 (AQP5), an isoform of membrane water channel aquaporins, is expressed
in the salivary and lacrimal glands. We surveyed the expression and immunohistochemical
localization of AQP5 in the rat digestive system. RT-PCR analysis revealed that
AQP5 is expressed in the submandibular gland, tongue, gastric corpus, pyloric
region, duodenum, and liver. Immunofluorescence microscopy using AQP5-specific
antibodies showed that AQP5 protein is present in the minor salivary glands of
the tongue, the pyloric glands, and duodenal glands. To distinguish apical and
basolateral domains of the plasma membrane of epithelial cells, double-immunofluorescence
staining for AQP5 and tight junction protein occludin was performed. In the minor
salivary gland, AQP5 was present in both the serous and mixed secretory end portions.
AQP5 was found in the apical membrane of the secretory cells including intercellular
secretory canaliculi demarcated with occludin. At higher magnifications, omega-shaped
indentations of AQP5 labeling were seen along the apical membrane, suggesting
a dynamic process for the apical membrane in exocytosis. Only weak labeling for
AQP5 was detected in the basolateral domain. In the stomach, AQP5 was detected
in the apical membrane of the pyloric gland secretory cells. In the duodenum,
AQP5 was restricted to duodenal glands, where it was localized to the apical membrane.
AQP5 was not detected in the intestinal glands or cells in the villi. These observations
show that AQP5 is localized mainly in the apical membrane, including intercellular
secretory canaliculi of secretory cells in the minor salivary glands, pyloric
glands, and duodenal glands. AQP5 appears to play an important role in water transfer
in these glands.
Correspondence: Prof. Kuniaki Takata, Ph.D., Department of Anatomy and Cell Biology,
Gunma University Graduate School of Medicine, Showa-machi 3-39-22, Maebashi, 371-8511,
Japan.
Tel: +81-27-220-7900, Fax: +81-27-220-7906
E-mail: takata@med.gunma-u.ac.jp
Title
Origins and pathways of fluid entering sublobular lymphatic
vessels in cat livers
Author
Raksawan Poonkhum, Koumkrit Pisetpaisan, Bai-jun Wang, Vipavee Anupunpisit, Yuko
Ohtani and Osamu Ohtani
Address
Department of Anatomy, Faculty of Medicine, Toyama Medical and Pharmaceutical
University, Toyama, Japan; Department of Anatomy, Faculty of Medicine, Srinakharinwirot
University, Bangkok; and Department of Anatomy, Faculty of Veterinary Medicine,
Kasetsart University, Bangkok, Thailand
Summary
The liver, which produces a large volume of lymph, has a lymphatic system which
can be classified into three categories: portal, sublobular, and superficial lymphatic
vessels. As little is known about the origin and pathways of sublobular lymph,
this study demonstrates pathways of interstitial fluid flowing into sublobular
lymphatic vessels. Livers from cats whose thoracic ducts were either ligated or
non-ligated were examined by light-, transmission electron- and scanning electron-microscopy
(SEM). Complete ligation of the thoracic duct caused significant dilation of the
hepatic sinusoids, the space of Disse, and channels passing through the limiting
plate. Sublobular interstitial space and sublobular lymphatic vessels were also
expanded. The channels between hepatocytes forming the limiting plate contained
collagen fibers, and connected the space of Disse with a sublobular interstitial
space. The alkali-water maceration/SEM confirmed that collagen fibers traversing
the layer of the limiting plate independently of blood vessels connected collagen
fibers in the space of Disse with those in the sublobular space. Complete ligation
of the thoracic duct also showed an accumulation of mast cells and plasma cells
in the sublobular interstitial space. Our data suggest that fluid in the space
of Disse flows along collagen fibers in channels traversing the limiting plate
as well as those along the sinusoids and central veins that drain into sublobular
veins, and enters the sublobular interstitial space to finally lead into sublobular
lymphatic vessels. Our study has also shown that hepatic lymphostasis causes the
accumulation of mast cells and plasma cells in the sublobular interstitial space,
which may be involved in lymphangiogenesis and fibrogenesis.
Correspondence: Prof. Osamu Ohtani, Department of Anatomy, Toyama Medical and
Pharmaceutical University, 2630 Sugitani, Toyama, 930-0194 Japan
Phone: +81-76-434-7205, Fax: +81-76-434-4010
E-mail: osmotani@ms.toyama-mpu.ac.jp
Title
Ontogeny of plasma cells in the early rat yolk sac
Author
Nagwa El-Nefiawy, Khaled Abdel-Hakim, Naohiro Kanayama, Nobihiko Suganuma, and
Toshihiko Terao
Address
Department of Obstetrics and Gynecology, and Department of Radiology, Hamamatsu
University School of Medicine, Hamamatsu, Infertility Center, Toyohashi Municipal
Hospital, Toyohashi, Japan
Summary
The present study investigated the development of plasma cells in the early rat
yolk sac (days 10-16 of gestation) by light microscopy, transmission electron
microscopy, immunoelectron microscopy, and indirect immunofluoresce techniques.
Cells delineating the morphology of plasma cells in the yolk sac were observed
as early as 12 days of embryonic life. As for positive immune staining for the
intra-cytoplasmic immunoglobulin (Ig) production (IgA, IgM and IgG), the intensity
of the immune staining was very weak on days 10 and 11 of gestation, while it
turned very dense on day 12 of gestation. At 14 days of gestation, the number
of positive cells was markedly reduced. Immunoelectron microscopy visualized products
of the immune reaction in cisterns of the rough endoplasmic reticulum. Conventional
electron microscopic examination of 12, 13, and 16-day yolk sacs confirmed the
development and differentiation of plasma cells with their well-known ultrastructural
features, making this the first study to demonstrate these in the early rat yolk
sac. The development of plasma cells in the early yolk sac implies the ability
of the yolk sac to effect a humoral immune response at this stage of fetal life.
The probable role of plasma cells in the yolk sac is also discussed.
Correspondence: Dr. Nagwa El-Nefiawy. Department of Obstetrics and Gynecology,
Hamamatsu University School of Medicine, 1-20-1 Handayama, Hamamatsu, 431-3192
Japan.
Tel: +81-053-435-2309, Fax: +81-053-435-2308
E-mail: nagwaebrahim@hotmail.com
Title
Expression of gastrin-releasing peptide (GRP) in the bovine
uterus during the estrous cycle
Author
Teguh Budipitojo, Motoki Sasaki, Shigenori Matsuzaki, Maria Bella C. Cruzana,
Toshihiko Iwanaga, Nobuo Kitamura, and Junzo Yamada
Address
Laboratory of Anatomy, Department of Basic Veterinary Sciences, Obihiro University
of Agriculture and Veterinary Medicine, Obihiro; Genetics Hokkaido Inc., Shimizu,
Hokkaido; and Department of Histology and Cytology, Division of Physiological
Sciences, Hokkaido University Graduate School of Medicine, Sapporo, Japan
Summary
Gastrin-releasing peptide (GRP) has been proposed as a novel regulatory peptide
in the reproductive tract. We previously demonstrated that GRP immunoreactivities
are found predominantly in the uterine gland epithelial cells of nonpregnant and
pregnant cows. The present study focused on the distribution of GRP immunoreactivity
and the expression of GRP mRNA in the bovine endometrium during the estrous cycle.
Tissues were collected from 21 uterine horns and bodies during the estrous cycle.
RT-PCR showed the expected GRP mRNA fragments (284 bp) in the tissues from all
stages of the cycle. In situ hybridization results ascertained the expression
of the GRP mRNA in the uterine gland epithelial cells and superficial epithelial
cells of the endometrium. Positive staining of GRP immunoreactivity in the uterine
gland epithelial cells was detected in both the uterine horn and body from all
stages of the cycle. In metestrus and diestrus stages, GRP was also detected in
the superficial epithelial cells of horn, but not in the body. The degrees of
GRP mRNA expression and intensities of GRP immunoreactivity in the endometrium
increased from proestrus to diestrus stages. These findings suggest that GRP may
be important both in the endometrial remodeling during the estrous cycle and in
the implantation and development of blastocysts.
Correspondence: Dr. Teguh Budipitojo, Laboratory of Anatomy, Department of Basic
Veterinary Sciences, Obihiro University of Agriculture and Veterinary Medicine,
Obihiro 080-8555, Japan.
Tel: +81-155-49-5350, Fax: +81-155-49-5354
E-mail: s04199@st.obihiro.ac.jp
Title
The expression of pancreatic endocrine markers in centroacinar
cells of the normal and regenerating rat pancreas: their possible transformation
to endocrine cells
Author
Tetsutaro Suzuki, Yuichi Kadoya, Yuichi Sato, Kimiya Handa, Tsuyoshi Takahashi,
Akira Kakita, and Shohei Yamashina
Address
Departments of Surgery and Anatomy, Kitasato University School of Medicine; and
Department of Molecular Diagnostics, Kitasato University School of Allied Health
Sciences, Sagamihara, Kanagawa, Japan
Summary
To determine the progenitor nature of centroacinar cells (CACs), we attempted
to compare the expression pattern of endocrine cell markers and PDX-1 (pancreatic
duodenal homeobox gene 1) in CACs of both the quiescent and the regenerating rat
pancreas. In the normal pancreas, most CACs were relatively small cells with sparse
cytoplasm and oval or elongated nuclei. In addition, we noticed a distinct population
of a small number of large cells with round nuclei in the centroacinar region.
By immunohistochemistry, 0.21% and 0.3% of CACs in normal rat pancreas were respectively
found positive for glucagon and insulin, being large CACs and designated as GL-CAC
and IL-CAC. They also exhibited the mRNA of each hormone by in situ hybridization
(ISH). The ISH signal for glucagon but not insulin was also detected in a subset
of small CACs (designated GS-CAC). The expression of PDX-1 was also observed in
subsets of small and large CACs (PS-CAC and PL-CAC, respectively). After a 90%
pancreatectomy, the relative frequency for GS-CACs, but not those for other CACs,
was significantly reduced in two days after surgery. On day 7 after surgery, the
number of GS-CACs recovered to preoperative levels, whereas GL-CACs, IL-CACs,
PS-CAC, and PL-CAC gradually increased to about double in number. From these results,
a portion of CACs was suggested to differentiated into endocrine cells. A possible
cell lineage is discussed for endocrine neogenesis during pancreatic regeneration.
Correspondence: Tetsutaro Suzuki, M.D., Department of Surgery, Kitasato University
School of Medicine,1-15-1, Kitasato, Sagamihara, Kanagawa, 228-8555 Japan
Tel: +81-42-778-9021, Fax: +81-42-778-9398
E-mail: tetsu@med.kitasato-u.ac.jp
Title
Tyramide signal amplification enhances the detectable distribution
of connexin-43 positive gap junctions across the ventricular wall of the rabbit
heart
Author
Craig S McLachlan, Patricia R Jusuf, Nicole Rummery, Sarah K Kummerfeld, Brett
Hambly, Mark A McGuire, and Virginia Turner
Address
Departments of Cardiology and Pathology, University of Sydney, Sydney, Australia
Summary
Previous mapping studies examinig the distribution and pattern of staining for
connexin-43 expression (the major ventricular gap junction protein) across the
ventricular wall have yielded variable findings. The aim of this study was to
determine if variations in the distribution of connexin-43 were due to histochemical
detection problems, i.e. cross-linking of antigenic sites as a consequence of
aldehyde fixation and/or due to low levels of protein expression within the epicardial
or endocardial regions of the heart. Immunoperoxidase staining of connexin-43
using the ABC method was carried out in crosssections of rabbit hearts at the
level of the papillary muscle. The following treatments were examined: the antibody
(Ab) only, Ab with 1/2 Tyramide Signal Amplification (TSA) or full TSA; antibody
with microwave antigen retrieval (AR); Ab + 1/2 TSA + AR and finally Ab + TSA
+ AR. Under light microscopy and using computerized image analysis the percentages
of ventricular cross-sectional transmural staining for the different treatment
groups were calculated: Ab amounted to only 55%; Ab + 1/2 TSA 63%; Ab + TSA 78%;
Ab + AR 72%; Ab + AR + 1/2 TSA 72% and Ab + AR + TSA 88%. The percentages of transumural
connexin-43 staining in both TSA + Ab and Ab + TSA + AR groups when compared to
Ab only were significantly greater p <0.01. The antigenic cross-linking due
to aldehyde fixation and low levels expression of connexin-43 are contributing
factors that influence the immunohistochemical detection of connexin-43 in the
mammalian heart. Methodological enhancement for the detection of connexin-43 in
this study was derived primarily from amplification of low background levels of
connexin-43 being expressed using the TSA protocol. This is supported by the significant
differences encountered when TSA was utilized in the protocol and compared with
antibody treatment only.
Correspondence: Dr. Craig Steven McLachlan, 46 The Sanctuary Westleigh, 2120,
Sydney, Australia
Tel: +61-2-9481-7790, Fax: +61-2-9351-3059
E-mail: reperfusion@hotmail.com
Title
Purification, cDNA cloning, and secretory properties of
FLRG protein from PC12 cells and the distribution of FLRG mRNA and protein in
rat tissues
Author
Yoshiyuki Ohsawa, Guiqin Zhang, Satoshi Kametaka, Masahiro Shibata, Masato Koike,
Satoshi Waguri, and Yasuo Uchiyama
Address
Department of Cell Biology and Neuronsciences, Osaka University Graduated School
of Medicine, Suita, Osaka, Japan
Summary
A 35 kD protein was isolated and purified from conditioned media of Bcl-2 cDNA-transfected
PC12 cells and its cDNA cloned. A database analysis showed that the 35 kD protein
is a rat homologue of the human FLRG protein. The biochemical as well as morphological
properties of the rat FLRG protein in PC12 cells were examined and its distribution
in rat tissues determined. The levels of FLRG mRNA expressed were low during the
fetal period, compared with those of follistatin mRNA. The distribution of FLRG
and follistatin mRNAs differed from each other after birth; the expression levels
of FLRG mRNA were abundant in the adrenal gland and testis, whereas those of follistatin
mRNA and activin A were markedly high in the ovary. The presence of FLRG mRNA
and/or protein was confirmed in spermatocytes at various differentiating stages
and in endocrine cells of both the adrenal cortex and medulla. When overexpressed
in PC12 cells, the FLRG protein was found to be stored in secretory granules of
the cells and largely secreted by a regulated pathway, while activin A enhanced
the constitutive secretion of the FLRG protein from wild-type PC12 cells, indicating
that the FLRG protein possesses dual properties in secretory pathways. The different
distribution between FLRG and follistatin mRNA suggests that, like follistatin
in the ovary, the FLRG protein may be involved in the maintenance of spermatogenesis
in the testis and the growth and function of adrenal tissue cells, probably by
regulating the functions of its binding partners such as the TGF-β superfamily
members.
Correspondence: Prof. Yasuo Uchiyama, Department of Cell Biology and Neuroscience,
Osaka University Graduate School of Medicine, 2-2, Yamadaoka, Suita, Osaka 565-0871,
Japan
Tel: +81-6-6879-3124; Fax: +81-6-6879-3129
E-mail: uchiyama@anat.med.osaka-u.ac.jp
