Temporal and dynamic changes in gingival blood flow during progression of ligature-induced periodontitis.

OBJECTIVES: To evaluate temporal changes in gingival blood flow (GBF) during progression of periodontitis in rats using a laser Doppler flowmeter (LDF) approach and to characterize morphological and biochemical features in the periodontium associated with GBF. MATERIALS AND METHODS: Forty-two Wistar rats were divided into a ligature-induced periodontitis group and a control group. To induce periodontitis, ligatures were tied around maxillary first molars bilaterally. GBF was measured in palatal gingiva at pretreatment and following ligature placement after 30 min, 1, 3, 7, 14, 21, and 28 days using LDF with a non-contact probe. Bone loss and gene expression in gingival tissues were assessed using micro-computed tomography (µCT) and quantitative polymerase chain reaction (PCR), respectively. Immunostaining for vascular endothelial growth factor (VEGF) in the maxilla was also histologically evaluated. RESULTS: GBF in the ligature group increased significantly compared with the control group 30 min after ligation. However, on days 3 and 7, GBF decreased in the ligature group. Also, after day 10, there was no difference in GBF between groups. The levels of alveolar bone loss, gene expression (interleukin-6, cluster of differentiation-31, VEGF-A, and lymphatic vessel endothelial hyaluronan receptor-1), and immunostained VEGF-positive vessels correlated well with changes in GBF. CONCLUSION PROGRESSION OF PERIODONTITIS: In rats was associated with a triphasic pattern of GBF, consisting of a short initial increase, followed by a rapid decrease, and then a gradual plateau phase.

Clinical anatomy of the anterior and posterior hepatic plexuses, including relations with the pancreatic plexus: A cadaver study.

The poor prognosis after surgery for pancreatic cancer or extrahepatic bile duct cancer has mainly been attributed to early lymph node metastasis, as well as a high frequency of perineural invasion along the peripancreatic neural plexuses or extrahepatic bile duct plexus. However, there has been no detailed morphological description of the anterior and posterior hepatic plexuses (AHP and PHP). In addition, the concepts of the pancreatic plexus and PHP are confused by surgeons. To assess the relations of the pancreatic plexus and hepatic plexuses from the morphological, developmental, and clinical perspectives, these plexuses were dissected in 24 cadavers. The PHP was found to be completely independent of the AHP. The PHP ran behind the portal vein, with most nerve fibers ascending along the bile duct to the gallbladder and the liver or descending to the distal common bile duct and duodenal papilla. Some branches of the PHP contributed to the pancreatic plexus, corresponding to pancreatic head plexus I as defined by the Japan Pancreas Society. The differences between the PHP and pancreatic head plexus I should be understood, even though liver function is not obviously affected after PHP excision for pancreatic head cancer. Further study is needed to determine whether there are functional differences between the AHP and PHP. Clin. Anat., 33:630-636, 2020. © 2019 Wiley Periodicals, Inc.

The mesopancreas and pancreatic head plexus: morphological, developmental, and clinical perspectives.

PURPOSE: Total mesopancreas excision has been found to be helpful for increasing no residual tumor resection rate and improving the prognosis of pancreatic cancer. This study analyzed the relationships among the mesopancreas and pancreatic head plexus from the morphological, developmental, and clinical perspectives. METHODS: Twenty-four cadavers were employed. The upper abdominal viscera were resected en-bloc with the hepatoduodenal ligament, abdominal aorta, and nerve plexuses, and the innervation of the pancreas was dissected. Ten additional cadavers were used for histological examination of the pancreatic head and neck, part of the duodenum, the superior mesenteric artery (SMA) and its surrounding tissues, and the related arteries and veins. RESULTS: As results, cross-sections of the SMA revealed 6-9 layers of membranous structures resembling the layers of an onion, and the nerve fibers of the superior mesenteric plexus ran between the layers. Loose areolar tissue, adipose tissue, and lymphatics existed between the SMA and the pancreatic head/uncinate process, along with abundant thin blood vessels and capillaries, but very few nerves were found approaching the pancreas. Several parallel layers of collagen fibers (so-called Treitz's fusion fascia) existed between the dorsal aspect of the pancreatic head and the aortocaval plane. CONCLUSION: The mesopancreas was continuous and connected with the para-aortic area. It may be better termed the mesopancreatoduodenum than the mesopancreas, as the duodenum-pancreas-SMA forms a complex morphological, developmental, functional, and pathological structure.

Analysis of the development of human foetal nasal turbinates using CBCT imaging.

PURPOSE: The morphological structure of the nasal cavity (NC) is important for endoscopic surgical treatment. The location of nasal turbinates, including the superior turbinate (ST), middle turbinate (MT) and inferior turbinate (IT), are well presented during the formation of the human NC in cone beam CT (CBCT) images. There is a complex relationship between the nasal sinuses, the maxillary sinus (MS), ethmoidal sinus and sphenoid sinus, during formation of the NC structure at the morphological level. There is a need to clearly define the relationships of these nasal elements at the ossification level, during development. METHODS: We investigated the three-dimensional construction of human foetal NC elements, including ST, MT, IT and vomer, using CBCT images from 16 weeks gestation (E16) to E31 (25 foetuses) and compared it to histochemical observations (E25). RESULTS: At the stage of ossification, the studied elements are elongated in the posterior region near the sphenoidal bone, showing that the locations of the ST, MT, and IT are important during formation of the NC. CBCT analysis revealed that the horizontal and vertical directions of nasal turbinates affect the formation of the human NC. CONCLUSION: The location and elongated development of the MT is one of the most important elements for NC formation. The relationship between the nasal sinus and nasal turbine at the level of ossification may provide useful information in clinical treatment of children.

Morphological observation and CBCT of the bony canal structure of the groove and the location of blood vessels and nerves in the palatine of elderly human cadavers.

PURPOSE: The greater and lesser palatine nerves and vessels supply the hard and soft palates, and the roots of these vessels and nerves run through a bony structure. However, the arrangement of blood vessels in the maxilla requires attention during clinical treatments, but detailed morphological information about changes in the greater and lesser palatine arteries and nerves during aging is unavailable. We therefore need detailed investigations of the morphology of the donor cadaver palatine using cone-beam computed tomography (CBCT) and macroscopic observations. METHODS: We investigated 72 donor cadavers using macroscopic segmentation and CBCT. The results' analysis examined differences in skull measurement parameters and differences between dentate and edentulous cases. RESULTS: The greater palatine artery and nerve showed different macroscopic arrangements in dentate and edentulous cadavers. We also classified three types of bony structures of the nerve and vessel roots in the molar regions of the palatine using CBCT images: the shallow groove, deep groove, and flat groove. The deep groove is the deepest of the three and is remarkable in edentulous elderly cadavers. CONCLUSION: This study of macroscopic and CBCT data provides information useful for planning dental implant surgeries and autogenous bone harvesting.

Unexpected ovarian malignancy found after laparoscopic surgery in patients with adnexal masses--a single institutional experience.

Laparoscopy has become the standard surgery for the treatment of benign ovarian tumors. The aim of this study was to evaluate the appropriateness of laparoscopy for ovarian tumors, including those with malignant potential. A total of 487 patients with adnexal masses underwent laparoscopic surgery in Social Insurance Chukyo Hospital from January 2000 to December 2012. We reviewed 471 cases that fulfilled the criteria set for this study, and examined 10 cases with unexpected ovarian malignancy to analyze their preoperative diagnosis, second surgery, postoperative chemotherapy, and prognosis. The ages of the 471 patients ranged from 13 to 50 years, with a median of 31. Nulliparous patients numbered 321(68.1%). Of all, 436 patients mostly consisted of those with endometrioma, benign ovarian neoplasm or functional cyst. In all, we histologically identified 10 women with malignancy: 6 with borderline ovarian tumors (BOT), 2 with ovarian cancer, and 2 with histologically rare tumors (immature teratoma and granulosa cell tumor). All patients with BOT were diagnosed with a mucinous histology. Two patients underwent both second radical surgery (hysterectomy and contra- or bilateral salpingo-oophorectomy) and chemotherapies that consisted of CBDCA and PTX or DTX. Thus, 2 patients underwent staging procedures, but the remaining 8 cases did not. None of them had evidence of recurrences. With accurate staging and careful postoperative follow-up, laparoscopic surgery could be a feasible initial operation for patients with adnexal masses including early-stage ovarian malignancy.

Analysis of vascular distribution and growth factors in human gingival tissue associated with periodontal probing depth.

SUMMARY: Vascular endothelial growth factor (VEGF) is a key regulator of blood vessel endothelium. Tissue levels of this angiogenesis marker are unknown in human gingival tissue, as is the correlation between vascular growth factors and hypoxia-inducible factor. We examined the expression of VEGF, type III tyrosine kinase receptors (VEGF-R2), platelet-endothelial cell adhesion molecule (CD31) and hypoxia-inducible factor (HIF) mRNA from human gingival tissue of the oral cavity. Tissue samples were from a small quantity of gingival sample biopsy with gingival sulcular depth (GSD) < 2 mm (Group 1), 2 to 4 mm (Group 2), and > 4 mm (Group 3). We found that the levels of VEGF-R2, CD31 and HIF mRNA were higher in the gingival tissue of Group 2 than that of Group 1, and VEGF in the Group 3 was also higher than that of Group 1. The different mRNA levels of these markers may reflect the mRNA levels reflect the vasculature state of gingival tissue based on GSD. VEGF-R2 and HIF also indicate the presence of an elongated blood vessel in the gingival tissue. In the early stage of angiogenesis, VEGF-R2 leads to expression of VEGF, and HIF-1 mediates increased VEGF expression in response to hypoxia in swollen tissues or during the expansion of periodontal tissues, which is useful in the early diagnosis of periodontal diseases.

A morphological study of the blood vessels associated with periodontal probing depth in human gingival tissue.

Gingival tissues in human cadavers were examined the blood vessel diameter in the depths of the gingival pockets such as three groups: gingiva adjacent to a sulcus of 2 mm (Group 1); gingiva adjacent to a 2-4-mm sulcus (Group 2); and gingiva adjacent to a sulcus of > 4 mm (Group 3). A meaningful significant difference was seen observed in gingival pocket side, intermediate and outer layer side regions of the gingiva. A meaningful significant difference was seen found in intermediate part and the outer layer of the gingiva in Group 3. Other gingival biopsies were performed on a human body donation specimen to examine CD-31 positive endothelial cells of blood vessels by an immnohistochemical method. Our results suggest that the periodontal probing depth reflect the blood vessel organization of human gingival tissue.

Understanding the formation of maxillary sinus in Japanese human foetuses using cone beam CT.

The formation of the maxillary sinus (MS) is tied to the maturation of the craniofacial bones during development. The MS and surrounding bone matrices in Japanese foetal specimens were inspected using cone beam computed tomography relative to the nasal cavity (NC) and the surrounding bones, including the palatine bone, maxillary process, inferior nasal concha and lacrimal bone. The human foetuses analysed were 223.2 ± 25.9 mm in crown-rump length (CRL) and ranged in estimated age from 20 to 30 weeks of gestation. The amount of bone in the maxilla surrounding the MS increased gradually between 20 and 30 weeks of gestation. Various calcified structures that formed the bone matrix were found in the cortical bone of the maxilla, and these calcified structures specifically surrounded the deciduous tooth germs. By 30 weeks of gestation, the uncinate process of the ethmoid bone formed a border with the maxilla. The distance from the midline to the maximum lateral surface border of the MS combined with the width from the midline to the maximum lateral surface border of the inferior nasal concha showed a high positive correlation with CRL in Japanese foetuses. There appears to be a complex correlation between the MS and NC formation during development in the Japanese foetus. Examination of the surrounding bone indicated that MS formation influences maturation of the maxilla and the uncinate process of the ethmoid bone during craniofacial bone development.

Observing the bony canal structure of the human maxillary sinus in Japanese cadavers using cone beam CT.

We observed the location of the posterior superior alveolar artery (PSAA) and nerve at the macroscopic level between the maxillary sinus (MS) and surrounding bone of the anterior region of the maxilla. This study was completed using cone beam computed tomography (CBCT) imaging of 19 human cadavers with 38 sides of Japanese origin (ranging in age from 59-94 years, mean 77.7 +/- 9.8 years) that were prepared for this study. The bony canal structure of the inner surface of the maxilla was clearly apparent in our results, and the bony canals were classified into three types according to the structure along the course of the PSAA: canal-like, ditch-shaped tunnel and fragmented, and the lest sides were undefined. Calcitonin gene-related peptide (CGRP)-positive fibers were identified along the PSAA in the bony canal of the maxilla by immunohistochemistry. The presence of the bony structure and CGRP-positive nerve fibers along the PSAA suggests that there is risk to the PSAA during surgery involving graft implant in the floor of the maxillary sinus.

Evaluation of the blood and nerve supply patterns in the molar region of the maxillary sinus in Japanese cadavers.

The maxillary sinus (MS) in the maxilla bone is located near the orbit, the nasal cavity and the oral cavity; however, the positioning of the constituent bones is complex. The posterior superior alveolar branches of the maxillary artery and nerve are distributed in the lateral wall of the MS. The courses of these blood vessels and nerves are restricted by the morphology of the craniofacial bones, and the landmarks used in dental implant treatment of these courses mainly run along the lateral wall of the MS. In this study, 19 human cadavers with 34 sides of Japanese origin (ranging in age from 59-94 years, mean 77.7 +/- 9.8 years) were prepared for measurement of the MS, the superior alveolar artery and the infraorbital artery using cone beam computed tomography (CBCT). The posterior superior alveolar artery (PSAA) of the lateral wall of the MS can be classified into one of three groups based on the supply pattern. In the greatest number of cadavers, the PSAA ran mainly to the lateral surface of the zone between the superior border of the alveolar foramen and the inferior border of the MS (53.0%, 18/34). In others, the PSAA ran to the zone between the infraorbital foramen and the superior border of the alveolar foramen (17.6%, 6/34); in a third group, the PSAA ran to the zone between the inferior border of the MS and the greater palatine foramen (23.5%, 8/34). The lest of two sides are spread out in this area (5.9%, 2/34). CBCT is the most accurate tool to evaluate important anatomical parameters, such as the distance of the blood supply, for the implant of grafts in the floor of the MS during surgical procedures.

Immunohistochemical study for relationship between vessel and lymphatic properties and tooth marks in human oral mucosa.

Angiogenesis is an important issue related to normal growth and differentiation, and it is a critical issue in the progression of human disease in oral mucosa. Tooth marks occur after clenching the teeth for a long period under muscle tension in the human oral cavity. However, the sites of angiogenesis, cell differentiation and microvessel density are not known for human mucosa with tooth marks. Therefore, we investigated the relationship between the markers of differentiation (Ki-67), angiogenesis (CD31, D2-40, VEGF-A), and marks from teeth in the second molar region using immunohistochemical methods. In addition, we compared these areas with the mucous membrane. Our results revealed blood and lymphoid vessels in irregular mucosa structures, and the vessels in the oral mucosa were observed in three types of samples: dentulous, denture attachment (containing partial teeth), and edentulous samples. The localization of the angiogenesis was related to the structure of the oral mucosa of connective tissue in humans, such as the mucosal fold-like of the buccal region. Using principal component analysis (PCA), we found that tooth occlusal condition, gender, anti-VEGF-A reaction levels in oral mucosa of the epithelium were positive factors in all groups, which is in contrast to the negative association of Ki-67 reaction in the epithelium and CD31 expression. In addition, Ki-67 reaction in oral mucosa had negative impacts, in contrast to the positive association of D2-40. These PCA properties provide useful information for future study of tumour progression or mechanical stress in remodelling of oral mucosa and angiogenesis. Moreover, mechanical stress of the occlusal condition may be correlated with tumour angiogenic activity and cell differentiation in human oral mucosa.

Distribution of glutamate receptor, ionotropic, kainate 1 and neuropeptide calcitonin gene-related peptide mRNAs during formation of the embryonic and postnatal mouse molar in the maxilla.

The neuropeptide calcitonin gene-related peptide (CGRP) is a well-characterized neurotransmitter. Glutamate receptor, ionotropic, kainate 1 (Grik1) has also been demonstrated to generate high-affinity kainate receptors. However, little is known about the roles of CGRP and Grik1 during the developmental formation of teeth. In this study, we endeavoured to analyse the expression and localization of CGRP and Grik1 mRNAs using in situ hybridization on the mouse maxilla during development from the embryonic stage (E18.5) to after birth (P10, P15 and P20). We found that hybridization with an anti-sense probe for CGRP clearly localized in the maxilla at E18.5 in contrast to that of P15 and P20. Hybridization with an anti-sense probe for CGRP was not detected in the dental pulp of molars in the maxilla at P10, which is in contrast to Grik1 mRNA at the same developmental stage. Hybridization with an anti-sense probe for Grik1 mRNA was detected in the basal region of the dental pulp of molars at P10 and P15. Finally, these markers were not detected in molars in the mouse maxilla at P20. The ratio of positive cells for the hybridization signals of Grik1and CGRP in the dental pulp decreased from E18.5 (p<0.001). These features in CGRP and Grik1r mRNAs may indicate roles of function during tooth development between embryonic and postnatal stages with root formation and erupted movements.

Morphogenesis of the ventral pancreas anlagen is influenced by the SMA branching pattern.

Developmentally, the uncinate process of the pancreas is derived from the ventral pancreatic anlagen, supplied by the superior mesenteric artery (SMA), and contains pancreatic polypeptide (PP)-rich islets of Langerhans. In contrast, the other parts of the pancreas originate from the dorsal anlagen supplied by the celiac system and contain PP-poor islets. This study was performed to investigate whether morphogenesis of the ventral pancreas anlagen is associated with the pattern of SMA branching. SMA branches to the pancreatic body were dissected in 44 cadavers. The cadavers were divided into two groups: the SMA group in which the SMA gave off branches to the pancreatic body and the General group in which it did not. In the SMA group, the ratio of the diameter of the SMA branch supplying the pancreatic body (SMA branch) to that of the SMA itself was calculated. After dissection was completed, tissues were collected from all pancreatic specimens for HE staining and for immunohistochemistry with PP and insulin antibodies. There were 25 cadavers in the General group and 19 in the SMA group. In 10/19 cadavers from the SMA group, PP-rich islets were confirmed in the pancreatic body. The SMA branch diameter ratio was significantly smaller in the SMA group cadavers with PP-poor islets (n = 9) than in cadavers with PP-rich islets (n = 10) (P < 0.001). These findings suggest a relation between the SMA branching pattern and the distribution of PP cells.

Precise anatomical resection based on structures of nerve and fibrous tissue around the superior mesenteric artery for mesopancreas dissection in pancreaticoduodenectomy for pancreatic cancer.

BACKGROUND: The aim of the present study was to investigate the feasibility of resection based on the nerve and fibrous tissue (NFT) structures around the superior mesenteric artery (SMA) for resectable pancreatic adenocarcinoma (R-PDAC) patients. METHODS: NFTs around the SMA were classified into four "intensive NTFs area" with spreading the NFTs around the SMA and three SMA nerve plexus regions without branching nerves according to autopsy findings. Complete dissection of four "intensive NTFs areas" was performed by pre-exposing three SMA nerve plexus regions without branching nerves as "dissection-guiding points" with SMA nerve plexus preservation (NFT-based resection). Among 157 R-PDAC patients undergoing pancreaticoduodenectomy, surgical outcomes of 78 patients with NFT-based resection were compared with 59 patients with half-SMA nerve plexus dissection and 20 patients without NFTs dissection. RESULTS: In the NFT-based resection group, 76.5% had tumor involvement and metastasis in each intensive NTFs area. Operative time, blood loss, and postoperative diarrhea rate were significantly lower in NFT-based resection than in half-SMA nerve plexus group (321 vs 390 min; P < .01, 228 vs 550 mL; P < .01, 5.1% vs 15.3%; P = .04, respectively). R0 rate and median overall survival significantly improved in NFT-based resection than in non-NFT dissection group (93.6% vs 65.0%; P < .01, 49.6 vs 23.6 months, P = .01). CONCLUSION: NFT-based resection may become a novel method for R-PDAC patients.

Expression of respiratory chain enzyme mRNA and the morphological properties of mitochondria in the masseter muscles of klotho mutant mice.

The activity of respiratory chain enzymes in a rat's masseter muscle changes as the animal ages; however, there is little information about the RNA transcript levels of mitochondrial enzymes in klotho mutant mice as they age. We measured the activities of NADH-ferricyanide oxidoreductase and NADH-O2 oxidoreductase, and the RNA transcript levels of NADH dehydrogenase, the mitochondrial isoform of ND1, the nuclear isoforms of the 51 kDa and 75 kDa subunits of Complex I, the nuclear isoform of cytochrome c, and the mitochondrial isoform of beta subunits of ATPase (Complex V). In addition, we measured the RNA transcript levels of catalase (CAT) and superoxide dismutase (SOD), which are associated with antioxidant proteins. Moreover, we measured ATP concentrations using a luciferin-luciferase assay, and we determined the amount of cytochrome c associated with mitochondria in both klotho mutant mice and wild-type mice. However, the mRNA levels of cytochrome c and Complex V components, the mRNA levels of CAT, SOD, and apoptosis-inducing factor (Aifm), and the protein level of cytochrome c remained constant as klotho mutant mice aged from 5 weeks to 7 weeks. In wild-type mice, these components (except for those of Complex I) increased over time. NADH-ferricyanide oxidoreductase and NADH-O2 oxidoreductase activities decreased in klotho mutant mice as they aged from 5 weeks to 7 weeks. A few large mitochondria were scattered between myofibrils, and 7-week-old klotho mutant mice displayed an increased number of irregular mitochondria with fewer cristae. Our results indicate that the klotho protein plays a role in the diminished functional adaptability of enzymes in the masseter muscle of klotho mutant mice throughout the aging process.

Expression of myosin heavy chain isoforms in the postnatal mouse masseter muscle.

We investigated the properties of the masseter muscle in mice from five to seven weeks of age. Myosin heavy chain (MyHC) isoforms were measured in the masseter muscle. The three types of muscle fibers (Type I, strong reaction; Type IIA, intermediate reaction; and Type IIB, weak reaction) were all present in the masseter muscle in five-weeks-old mice and seven-weeks-old mice, the three types could be clearly distinguished by their enzyme activity. The percentage of Type IIB fibers (above 50%) was the highest among all fiber types both 5- and 7-weeks-old mice. The mRNA levels for myosin slow and myosin IIb increased significantly between 5 and 7 weeks. These observations suggest that muscle fiber size, muscle fiber types and mRNA levels of the MyHC isoforms all contribute to the diminished functional adaptability of enzyme activity in the masseter muscle.

Distribution of the neuropeptide calcitonin gene-related peptide-α of tooth germ during formation of the mouse mandible.

Calcitonin gene-related peptide-α (CGRPα) is a neurotransmitter that is related to bone formation during development. However, CGRP expression is not well known to affect the formation of teeth during development. During tooth germ development, the relationships among CGRPα, calcitonin receptor-like receptor (CRLR), amelogenin (AMELX), dentin sialophosphoprotein (DSPP), osteopontin (OPN) and osteocalcin (OCN) are unclear despite various tooth and osteogenesis markers. Our real-time RT-PCR results showed that the expression levels of CGRPα mRNA gradually decreased, in contrast to the mRNA abundances of CRLR, AMELX, DSPP, OPN, and OCN, which rapidly increased from E14.5 to P1 in the mandible. In situ hybridization using an antisense probe for CGRPα mRNA showed significant localized expression levels around the tooth bud at E14.5 and epithelial cells near the dental ledge and outer and inner enamel epithelium at E17.5 compared to those at P1. The localization of the anti-CGRPα antibody reaction revealed a strong positive reaction at the surface layer of oral epithelial cells at E14.5 and oral epithelial cells of the dental lamina around the dental ledge depression in the mandible of E17.5 mice using immunohistochemical methods The different anti-CGRPα reaction revealed its important roles during tooth formation at the postnatal stage. CGRPα mRNA was also detected in the interactions of tooth germ with the formation of odontoblast and amelobast layers from dental papilla and inner enamel epithelium. CGRPα may also be related to tooth germ development. Furthermore, CGRPα is an important tooth and bone formation marker, and bone cells provide further evidence of a role in mandibular development in contrast to inflammatory systems.

The distribution of nerves supplying the testis, epididymis and accessory sex glands of Suncus murinus.

Chronic testicular pain remains an important challenge for urologists. Investigation of the innervation of male gonads thus becomes essential for deepening our understanding of their regulatory roles in male reproductive physiology and pathophysiology. Studies of testicular innervation are mainly limited to the intratesticular peptidergic nerves of the testis by immunohistochemical and acetylcholinesterase histochemical investigations in some animals. Little is known about the detailed, overall distribution in general experimental animal testis. In this study, the distribution of nerves supplying the testis, epididymis and accessory sex glands of Suncus murinus was investigated by whole mount immunohistochemistry staining using a neurofilament protein antibody. Testicular nerves arose through three routes: nerves deriving from the mesenteric and renal plexuses accompanied the testicular artery, entering into the testicular hilum through the superior ligament of the testis. The nerves originating from the hypogastric plexus then ran along the internal iliac artery, deferential artery, and passed through the mesoductus deferens or mesoepididymis, innervating the cauda and corpus of the epididymis, the vas deferens and the inferior pole of the testis. The third route arose from the pelvic plexus, distributed in the seminal vesicle and the prostate. The density of nerve fibers was higher in the cauda epididymidis than in the testis, and more abundant in the vas deferens. The different origins and distribution densities of testicular nerves in S. murinus may serve different neuronal regulatory functions, and, therefore, S. murinus may be an important model animal for understanding the different characteristics of testicular pain.

Immunocytochemical localization of vascular endothelial growth factor and vascular endothelial growth factor receptor-2 of the human deciduous molar tooth germ development in the human fetus.

Vascular endothelial growth factor (VEGF) is a key regulator of blood vessel endothelial development. We used immunohistochemical methods to demonstrate the localization of VEGF and its receptors, showing the specific expression pattern of VEGF and VEGF receptor in the human deciduous tooth from the cap to late bell stages in the human fetus. Immunoreactivity to VEGF and its receptor VEGF receptor-2 (VEGFR-2) was intensely positive in the inner enamel epithelium at the cap stage and ranged from negative to moderately positive in the bell stage. At the late bell stage, VEGF immunoreactivity was mainly positive but weak for VEGFR-2. The intensity of VEGF and VEGFR-2 in odontoblasts increases from cap stage to late bell stage. We postulate that the dissimilar expression of VEGF in inner enamel epithelium, ameloblast and odontoblast during each stage of human tooth development may affect tooth germ formation.