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The hands of the American black bear (Ursus americanus), the sun bear (Helarctos malayanus), the polar bear (Ursus maritimus), and the lion (Panthera leo) were dissected and the mass of the intrinsic hand muscles were systematically recorded to explore possible interspecies variation. Muscle mass was divided by the third metacarpal bone size for normalization. The results indicated that the normalized muscle masses of the thenar muscles were larger in the three bears than the lion, and the abductor pollicis muscle was larger in the sun bear than other bears. For the abductor digiti minimi muscle, the normalized muscle mass was larger in the three bears than the lion, but smaller in the polar bear among three bears. One limitation of this study is that here we provided only one specimen for each species, and thus the present results need to be confirmed by examining a larger number of cases in future studies. However, these differences in the intrinsic hand muscles of the four species may reflect adaptation for their different habits.

Comparative analysis of the foot muscle architecture among extant great apes is important for understanding the evolution of the human foot and, hence, human habitual bipedal walking. However, to our knowledge, there is no previous report of a quantitative comparison of hominoid intrinsic foot muscle dimensions. In the present study, we quantitatively compared muscle dimensions of the hominoid foot by means of multivariate analysis. The foot muscle mass and physiological cross-sectional area (PCSA) of five chimpanzees, one bonobo, two gorillas, and six orangutans were obtained by our own dissections, and those of humans were taken from published accounts. The muscle mass and PCSA were respectively divided by the total mass and total PCSA of the intrinsic muscles of the entire foot for normalization. Variations in muscle architecture among human and extant great apes were quantified based on principal component analysis. Our results demonstrated that the muscle architecture of the orangutan was the most distinctive, having a larger first dorsal interosseous muscle and smaller abductor hallucis brevis muscle. On the other hand, the gorilla was found to be unique in having a larger abductor digiti minimi muscle. Humans were distinguished from extant great apes by a larger quadratus plantae muscle. The chimpanzee and the bonobo appeared to have very similar muscle architecture, with an intermediate position between the human and the orangutan. These differences (or similarities) in architecture of the intrinsic foot muscles among humans and great apes correspond well to the differences in phylogeny, positional behavior, and locomotion.

The 12 left digits of the thoracic limb of Holstein female cows were obtained from a slaughterhouse, and 13 linear measurements of skeletal specimens of the digits of the thoracic limb were used in this study. Bivariate plots, regressions and correlation analyses were performed to assess the relationships between osteometric data and age, and between osteometric data and body size. The geometric mean (GM) of the metacarpal size was used as a proxy of body weight. The results of the regression analysis demonstrated that the length and the width of the distal phalanx were significantly correlated with age, whereas those of other bones were not. In addition, the correlations of the distal phalanx tended to be higher with age than with the GM of the metacarpal size, and their skeletal measurements tended to be longer in older animals than in younger animals. These findings suggest that the distal phalanx is slightly elongated and enlarged in its solear aspect with increasing age in skeletally mature cows. Moreover, although the side difference in the distal phalanx between the lateral and medial digits did not increase significantly with age, the solear aspect of the distal phalanx tended to be rougher, and deformation of the flexor tubercle tended to be more pronounced in the medial digit compared with the lateral digit. Therefore, in the distal phalanx of the front feet, the skeletal deformation with age and asymmetrical bone development might be related to the pathogenesis of claw horn lesions, as in the hind feet.

Cytosolic and secretory carbonic anhydrase isoenzymes (CA-II and CA-VI, respectively) were detected by immunohistolocalization using specific canine CA-II and CA-VI antisera. CA-II and CA-VI were identified in glands associated with the canine lacrimal apparatus, such as lacrimal gland, superficial gland of the third eyelid (third eyelid gland) and tarsal gland. CA-II and CA-VI mRNA signals were also detected by reverse-transcriptase polymerase chain reaction in the same tissues. Some serous acinar cells and duct segments in the lacrimal gland and serous acinar cells in the third eyelid gland were immunopositive for anti-CA-II and CA-VI antisera. In particular, some immunopositive acini to CA-II and CA-VI on the edge of the third eyelid gland are histologically similar to sebaceous gland cells. Sebaceous gland cells in the tarsal and ciliary glands also showed immunopositivity to both CA antisera. CA-II and CA-VI gene transcripts were detected in the same regions. These results suggest that secreted CA-VI may form together with cytosolic CA-II, a high-activity isozyme mostly considered as a bicarbonate producer, in a mutually complementary system for the maintenance of bicarbonate levels to regulate pH in tear fluid and protect the corneal epithelia against injuries. In sebaceous gland cells in the lacrimal apparatus, CA-VI may be related to lipogenesis in an unknown function.

Obesity results from the dysregulation of energy balance throughout the entire body. Although the ubiquitin system participates in many cellular processes, its contribution to the balance of energy in the body remains poorly understood. Here, we show that ubiquitin C-terminal hydrolase (UCH)-L3, one of the deubiquitinating enzymes, contributes to the regulation of metabolism. Uchl3(-/-) mice displayed a reduction of adipose tissue mass and were protected against high-fat diet (HFD)-induced obesity and insulin resistance. Uchl3(-/-) mice given both a normal chow and an HFD had an increased whole-body energy expenditure accounting for the reduction of adipose tissue mass. Activation of AMP-activated protein kinase (AMPK) in skeletal muscle has been reported to increase fatty acid beta-oxidation, leading to the elevation of the whole-body energy expenditure. Consistently, increased activation of AMPK and fatty acid beta-oxidation was observed in skeletal muscle of Uchl3(-/-) mice. Mouse embryonic fibroblasts derived from Uchl3(-/-) mice also showed increased activation of AMPK, indicating that UCH-L3 is involved in a cell-autonomous down-regulation of AMPK. These results suggest a role for UCH-L3 in the regulation of AMPK activity and whole-body energy metabolism.

We investigated the histological changes of extra-intestinal organs, such as the liver, kidney, lung and pancreas in SAMP1/Yit mice, a human Crohn's disease model, using immunohistochemical techniques. The perivascular cellular infiltration was detected around the small vessels after 30 weeks. These infiltrating cells consisted of many CD4-positive T-lymphocytes, and small numbers of CD8- positive T-lymphocytes and IgG-positive B-lymphocytes. MAdCAM-1 and VCAM-1 were detected in vascular endothelial cells in non-affected regions of 13 and 20 week-old, as well as in the affected regions showing perivascular cellular infiltration after 30 weeks. In addition, integrin alpha4beta7 was detected on these infiltrating cells in the perivascular regions after 30 week-old. LT-beta and IL-12, cytokines of the Th-1-type immune response, were not observed in these affected regions. However, IL-4, one of the cytokines of the Th-2-type immune response, was detected on the perivascular infiltrating cells after 30 week-old. These results revealed that the changes in extra-intestinal organs were mainly caused by infiltration of CD4-positive T-lymphocytes into the perivascular regions in SAMP1/Yit mice. These cellular infiltrations were thought to be initiated by adhesion of CD4-positive T-lymphocytes to the endothelial cells mediated by MAdCAM-1 and integrin beta7. Immunohistochemistry for Th related cytokines indicated that the perivascular cellular infiltration was developed by the Th-2-type immune response in the extra-intestinal organs of SAMP1/Yit mouse.

The WW domain containing E3 ubiquitin protein ligase 1 (WWP1) is classified into one of ubiquitin ligases which play an important role in ubiquitin-proteasome pathway. Previously, we identified the WWP1 gene as a candidate gene of chicken muscular dystrophy by linkage analysis and sequence comparison. However, the mechanism causing pathological changes and underlaying gene function remains elucidated. In the present study, we analyzed the WWP1 gene expression in various muscles and tissues of normal chickens, and compared with those from muscular dystrophic chickens. Two mRNA isoforms were detected in all tissues examined and revealed almost equal expression level. The WWP1 expression of dystrophic chickens was decreased in almost all skeletal muscles including unaffected muscles. These data indicate that there might not be a causal relationship between the alteration of WWP1 expression level and the severity of muscular dystrophy.

獣医歯科学における顎顔面領域の骨組織再生治療の試みは,重度歯周炎などによる骨欠損部を補う手段として注目されている。現在までにバイオマテリアルやサイトカインを用いた骨組織の再生治療が検討され,その効果が証明されている。本実験は細胞増殖因子としてbasic Fibroblast Growth Factor (bFGF)を,バイオマテリアルとして非吸収性のバイオガラス,ハイドロキシアパタイト,吸収性のβ三リン酸カルシウムを,人工的に作製した犬顎骨抜歯窩に埋入し,放射線学的ならびに組織学的に評価し,各バイオマテリアルの有効性を検討した。その結果,実験期間を通して臨床状態に異常は見られなかった。放射線学的ならびに組織学的評価において,実験部位により差はあるものの,バイオマテリアル埋入部位で骨再生が促進され,多くの新生骨が再生していた。また,埋入したバイオマテリアルによる炎症反応は認めなかった。以上より,各バイオマテリアルは生体親和性に優れ,各バイオマテリアルとbFGFを利用することは有用であると考えられた。, The approaches for the bone tissue engineering in the maxillary region of veterinary density is receiving the attention as a means of restoring the bone defects caused by the disease such as serious periodontitis. The challenges of bone tissue engineering with the use of biomaterial or cytokines have proved their effects. In this study, we used the basic fibroblast growth factor (bFGF) with three different kinds of biomaterials, non-absorbable bio-glass, hydroxyapetite, and beta-tricalcium phosphate, as the sources of bone tissue engineering and filled in the artificial pocket of dental extraction. The effectiveness of each biomaterial was evaluated radiographically and histologically. None of the biomaterials showed signs of clinical abnormalities through out the time of experiments. Moreover, all of the biomaterials showed osteoanagenesis and regeneration of new bones, with some difference of effectiveness dependent on the site of filling. The inflammatory responses at the site of biomaterial filling were neither observed. Thus, these results indicate that each biomaterial not only have advantage on biocompatibility but also shows effectiveness as a source of bone tissue engineering in combination with bFGF.

The musculature of the hip and thigh in the orangutan has been described previously. Anatomically, there are various descriptions among primates in those structures, in particular, the relationship between M. biceps femoris and M. gluteus maximus, their derivatives, and the muscle segment. However, a detailed innervation system to this ischiofemoral part has not been described, thus there is still uncertainty as to with which muscle it is associated. In this analysis, we examined the gross anatomy of the hip and thigh muscles of the orangutan and chimpanzee, including their innervation. Also, a comparison was made with documented data of other primates. As a result of these observations, it was found that the ischiofemoral part in the orangutan is innervated by the same sciatic nerve branch (the common peroneal nerve) as the long head of M. biceps femoris, but not by the same nerve as M. gluteus maximus. Therefore, the ischiofemoral part is appropriately considered as a part of the long head of M. biceps femoris. It appears that this morphologic feature is an adjustment to the arboreal life of the orangutan. The development of the flexor complex of the thigh is necessary for this arboreal adaptation, resulting in a unique musculature of M. biceps femoris in the orangutan.

Immunolocalization of the secretory form of carbonic anhydrase isoenzyme, CA-VI were studied using a specific canine CA-VI antiserum, and CA-VI mRNA signals were also investigated using the reverse-transcriptase polymerase chain reaction (RT-PCR) in canine nasal mucosal epithelia and glands. Immunoreactivity to CA-VI was positive throughout the mucosal epithelial cells and in the cytoplasm of serous acinar and ductal epithelial cells of the nasal mucosa and glands, including the vestibule of the nose, but the mucous acinar cells of the glands were immunonegative. We detected CA-VI gene transcripts in the same regions as the CA-VI immunoreactivity. The physiological roles of CA-VI in the nasal mucosal epithelium and glands might maintain bicarbonate levels in nasal secretions and protect the mucosa against acid.

Dietary habits must be considered as one of the major potential factors resulting in acquired malocclusions in rabbits. Although the dentition of the wild rabbit and the domesticated laboratory rabbit are basically identical, dietary habits are noticeably different. Therefore, the prevalence of tooth problems between these lagomorph species were investigated anatomically and radio-graphically. Mean measurements of the skull and dental arches suggested that wild rabbits have slightly shorter and wider skulls and dental arches compared with domestic laboratory rabbits. Root elongation of incisors and check teeth, and periodontal disease were more frequently observed in domestic laboratory rabbits. Diagnostic radiographs from domestic pet rabbits showed relatively higher crowns, severe root elongation, and advanced periodontitis. These results do not provide definitive evidence that dietary habits cause malocclusions, however they suggest that diet is a major factor in the initiation of malocclusions in rabbits.

Summary To clarify whether striated duct cells in canine salivary glands synthesize secretory carbonic anhydrase (CA-VI), as is the case with serous acinar cells, the present study utilized laser microdissection to harvest striated duct cells from canine parotid and submandibular glands, and total RNA extracted from these cells was then amplified by reverse transcription-polymerase chain reaction to assess CA-VI gene expression. The results confirmed the local expression of CA-VI mRNA in striated duct cells. This clarified that, in canine salivary glands, CA-VI is synthesized in not only serous acinar cells, but also striated duct cells.

Muscular dystrophies, a group of inherited diseases with the progressive weakness and degeneration of skeletal muscle, contain genetically variable diseases. Though chicken muscular dystrophy with abnormal muscle (AM) has long been known, the gene responsible has not yet been identified. In this study, a resource family for AM was established with 487 F2 individuals and 22 gene markers, including microsatellite and insertion–deletion markers, were developed. The haplotypes were analyzed with these markers for the candidate region of GGA2q described in a previous study. The candidate region was successfully narrowed down to approximately 1Mbp. The region included seven functional genes predicted as the most likely AM candidates.

Wistar系ラットの突然変異体として発見された,振戦を示すミュータントラット(振戦ラット)の組織学的変化について検討した。本研究では生後5,9,13,17,48週齢の振戦ラットについて,HE染色標本観察によるプルキンエ細胞数の変化や形態学的変化を観察した。また,星状膠細胞の動態を調べるために抗Glial Fibrillary Acidic Protein (GFAP)免疫染色を,小脳や小脳関連神経核における神経細胞の変性の有無について調べるためにFluoro.Jade B染色を行い,観察を行った。HE染色標本の観察の結果,生後5週齢の振戦ラットの小脳では著変は認められなかったが,生後9週齢以降の振戦ラットでは1～IX葉においてプルキンエ細胞の脱落が認められた。生後48週齢の小脳皮質ではX葉を除く,全ての葉の分子層と,一部の葉で穎粒層の菲薄化が認められた。また,全ての週齢において,小脳関連神経核や錐体路では顕著な変化は認められなかった。生後9～17週齢の振戦ラットでは小脳の分子層のバーグマングリアや小脳髄質の星状膠細胞に,正常対照ラットと比べて強い抗GFAP免疫陽性反応が認められた。生後5週齢の振戦ラットでは分子層の樹状突起に,生後9～17週齢の振戦ラットではプルキンエ細胞体ならびに樹状突起,バーグマングリア,髄質に存在する星状膠細胞にFluoro-Jade B陽性反応を認めた。本ラットにおいて,生後5週齢でプルキンエ細胞の樹状突起から変性が生じ,変性が細胞体に及んで,プルキンエ細胞が脱落することが判明した。プルキンエ細胞の脱落が認められた小脳のI～IX葉には,脊髄小脳路や橋小脳路からの神経線維が伸びており,本ラットの病態変化にこれらの神経路が関与している可能性があるが,異常は認めなかった。小脳に変性が生じるラットはいくつか知られているが,本ラットは1)変性部位が小脳に限局している,2)X葉に変化がみられない,3)小脳以外の部位や血液性状,繁殖力などに異常がないこと等が特徴である。これらの点に注目して解析を進めるとともに,生後早期の樹状突起の微細構造の観察や,さらに加齢の進んだ個体の解析などを行うことにより,本ラットの詳しい病態解析に繋がるものと考えられる。, A new neurological rat has been found in the Wister strain of rats. The mutation is inherited as an autosomal recessive traits and is manifest clinically by wobble gait and tremor after 9 weeks of age. In this study histopathological examinations were performed in order to investigation a change in the number of Purkinje cells and general histological change with H-E staining, distribution of astrocyte with immunohistochemical staining and the presence of the degeneration of Purkinje cell with Fluoro-Jade B reaction in the cerebellum and related nuclei at 5, 7, 9, 13 and 48 weeks of age. The loss of Purkinje cells was recognized in lobules I-IX from 9 weeks of age. Thinnings of molecular layer and granular layer were found in mutant rat at 48 weeks of age. In mutant rat at 9, 13 and 17 weeks of age, reactive strocytes with intense immunoreactivity against anti-GFAP antibosy were distributed in molecular layer (Bergmann's glial cell) and cerebellar medulla. Fluoro-Jade B positive reactions were found in dendrites of Purkinje cells at 5 weeks of age. At 9, 13, 17 weeks of age, cell bodies, dendrites of purkinje cells, Bergmann's glial cells and astrocytes of cerebellar medulla. In present study, histopathological examination revealed degeneration in this mutant occurred first at dendrite of Purkinje cell, and then extended gradually from dendrite to the cell body of Purkinje cell. Though it is known lobules I-IX found degeneration and loss of Purkinje cells in mutant rat were associated with spinocerebellar tract and pontocerebellar tract, no histopahological change were recognized in these tracts. Unique features of this mutant rat are 1) degeneration is confined to cerebellum, 2) No histopahological change is found in lobule X, 3) Except for the cerebellum, There is no abnormality in blood examination and fertility. Further study, for instance electromicroscopic syudy in dendrites at early stage after birth or investigation of mutant rat after 48 weeks of age will revealed mechanism for degeneration and histopahological features in detais.

Summary The lymph drainage routes from the abdominal cavity in rats were observed at 3 min, 1, 2 and 4 h after India ink was administered intraperitoneally. Four systems of lymph drainage routes from the peritoneal cavity were observed. Three minutes after injection, the drainage route travelled via the intrathoracic lymph vessels located along the internal thoracic artery and returned to the anterior mediastinal lymph nodes. One hour after injection, the drainage route travelled via the lymph vessel located along the left phrenic nerve in addition to the drainage route observed at 3 min. Two and four hours after injection, in addition to the above-mentioned routes, the drainage that had travelled via the thoracic duct continued along the right side of the aorta and was also observed in the lateral lymph vessel located on the vertebra. These findings suggest that lymph or cells absorbed into the peritoneal cavity at first travel towards the anterior mediastinal lymph nodes in the thorax via the ventral lymphatic channels, and then gradually course through the dorsal lymphatic channels. These routes may serve as a route for transporting cancer cells and other cells from the peritoneal cavity.

Summary In mammals, a pair of ejaculatory ducts exists in the urethra at the seminal colliculus. The detailed anatomical structures of the distal end of the ejaculatory ducts of Sprague-Dawley rats were investigated by the computer-assisted three-dimensional reconstruction analysis using light-microscopic serial sections. A three-dimensional reconstruction revealed that in adult rats, the ejaculatory sinus pair consists of two parts: the cranial section – a compartment region composed of a fusion of the ampullary gland duct and the seminal vesicle duct, and the caudal section – a grooved region composed of a long slitlike ejaculatory ostium that extends into the urethra on both sides of the seminal colliculus. But the sphincter structure was not observed. The long axis of the compartment region was approximately 58 μm in length, and that of the groove region was approximately 495 μm. Although many epithelial glands ducts were distributed throughout the ejaculatory sinuses, the prostate and coagulation gland ducts did not open in these sinuses. The urethra was composed of transitional epithelium, while the ejaculatory sinuses were composed of single to stratified cuboidal epithelium. The ejaculatory ducts continued to the ejaculatory ostium in male adult Sprague-Dawley rat were composed of the seminal vesicle ducts received the ampullary gland ducts.

To precisely understand how higher cognitive functions are implemented in the prefrontal network of the brain, optogenetic and pharmacogenetic methods to manipulate the signal transmission of a specific neural pathway are required. The application of these methods, however, has been mostly restricted to animals other than the primate, which is the best animal model to investigate higher cognitive functions. In this study, we used a double viral vector infection method in the prefrontal network of the macaque brain. This enabled us to express specific constructs into specific neurons that constitute a target pathway without use of germline genetic manipulation. The double-infection technique utilizes two different virus vectors in two monosynaptically connected areas. One is a vector which can locally infect cell bodies of projection neurons (local vector) and the other can retrogradely infect from axon terminals of the same projection neurons (retrograde vector). The retrograde vector incorporates the sequence which encodes Cre recombinase and the local vector incorporates the “Cre-On” FLEX double-floxed sequence in which a reporter protein (mCherry) was encoded. mCherry thus came to be expressed only in doubly infected projection neurons with these vectors. We applied this method to two macaque monkeys and targeted two different pathways in the prefrontal network: The pathway from the lateral prefrontal cortex to the caudate nucleus and the pathway from the lateral prefrontal cortex to the frontal eye field. As a result, mCherry-positive cells were observed in the lateral prefrontal cortex in all of the four injected hemispheres, indicating that the double virus vector transfection is workable in the prefrontal network of the macaque brain.

This macroscopic study firstly examined the precise locational information of the canine ciliary body, i.e., the ciliary crown and the ciliary ring in the beagle. The safe and effective transscleral laser photocoagulation technique requires the accurate location of the ciliary body. In both sides of the eyeball in 10 beagle dogs, the width of the ciliary ring and the distance from the limbus to the ciliary ring were measured with calipers using a stereomicroscope at the 8 points. The widest portion of ciliary body was found at the dorsal to ventro-temporal area of the lateral canthus (lateral portion of the eyelid; ear side). In contrast, the narrowest portion was seen at the ventro-nasal to nasal area of the medial canthus (medial portion of the eyelid; nasal quadrants). Use of transscleral photocoagulation at the present narrowest area of ciliary body may carry a high risk of destruction of the optic portion of retina.

In the present study, we firstly demonstrated immunohistochemical expressions of secretory carbonic anhydrase (CA-VI) isozyme in bovine forestomach, large intestine and major salivary glands. CA-VI was detected in basal layer epithelial cells of esophageal and forestomach stratified epithelium, in mucous cells of upper glandular region of large intestine, in serous acinar cells of the parotid gland, in serous demilune cells and some ductal liner cells of mandibular, monostomatic sublingual and esophageal glands. These immunohistolocalizations suggested that bovine CA-VI plays various roles in pH regulation, maintenance of ion and fluid balance, and cell proliferation.

雌豚では,発情期に外陰部の腫脹や充血などの特徴的な変化が見られる。この変化はEstrogenの生理的作用である。このとき生殖器官組織の経時的変化も認められ,その変化に関係する生理的に多様な機能を有する肥満細胞(TB陽性細胞)分布の動態に注目をした。17-βestradiol(E_2略)を用いて発情期の状態を再現し,その時の生殖器に見られる組織学的変化と肥満細胞の関連性を検討した。供試動物は,生後月齢のランドーレス,大ヨークシャー雑種の雌に。E_2投与した後,1・2・4・6・8・10日目に各々卵巣,子宮角,子宮頚管,膣部,外陰部とその周囲の皮膚を採取した。生殖器官の組織学的変化と肥満細胞の分布について観察し,検査はHE法とTB(異調性染色)法を用て組織中の肥満細胞を算定した。結果は,副生殖器官と外陰部周囲の皮膚部における組織変化が,E2投与で粘膜及び表皮細胞の増殖,粘膜固有層の拡張と水腫,好中球・リンパ球の浸潤等が2日目から4日目に顕著に認められた。卵巣は,4日目から6日目に卵胞の発育が見られた。採材した器官すべてに組織中に4日目から6日目に肥満細胞の分布が増加した。更に,特徴的に卵巣髄質,外陰部と,その周囲皮膚の真皮層に肥満細胞は多数認められた。これらの事から未成熟雌豚にE_2投与すると生殖器組織が経時的変化し,特に粘膜組織の増殖と水腫性,血管拡張性ならびに白血球浸潤変化が著明に認められた。この変化と合致するように肥満細胞の増数的変化が見られた。以上のことから肥満細胞の変化は,E_2と極めて密接な関係性があることが示唆された。, Specific changes, such as swelling and erythema of the external genitalia, take place in sows at the time of estrus. These changes are caused by estrogen. At the same time, progressive histological changes are also observed in the reproductive organs. In this study we focused on the changes in the distribution of mast cells (toluidine blue [TB] positive cells), which have various physiological functions and are related to the changes described above. We used 17-β estradiol (E_2) to induce estrus in sows, and then examined the relationship between histological changes in the reproductive organs and mast cells. We administered E_2 to one-month- and sixmonth-old Landrace x Large White sows, and sampled tissue from the ovary, uterine horn, cervical canal, vagina, external genitalia and skin around the external genitalia on days 1, 2, 4, 6, 8 and 10 following administration. Histological changes in the reproductive organs and the distribution of mast cells were examined by means of the HE method and TB (metachromatic staining) method. The number of mast cells in tissue and around arteries/veins was counted. With regard to histological changes in the accessory reproductive organs and skin surrounding the external genitalia, thickening of the mucosa, proliferation of epidermal cells, expansion of lamina propria mucosae, edema, and infiltration of neutrophils and lymphocytes were pronounced between day 2 and day 4. In the ovary, significant growth in the follicles was seen between day 4 and day 6. In all organ tissues, the distribution of mast cells increased between day 4 and day 6. In addition, a large number of mast cells were observed, particularly in the medulla of the ovary, the external genitalia and the dermis surrounding the external genitalia. As such, when E_2 was administered to immature sows, the reproductive organs showed progressive histological changes, and in particular, thickening of the mucosal tissue, edema, dilation of blood vessels, and infiltration of white blood cells were significant. The number of mast cells increased in response to these changes. These findings suggest that changes in the number of mast cells are closely related to E_2.

Equine carbonic anhydrase isozymes (CA-I and CA-II) were purified from erythrocytes by several column chromatography. Polyclonal anti-CA-I and anti-CA-II sera were produced in rabbits. Sensitive competitive enzyme-linked immunosorbent assays (ELISA) were established to determine the developmental changes in CA-I and CA-II levels in equine erythrocytes. Concentrations of CA-I and CA-II in erythrocytes from 150 clinically normal thoroughbreds (123 racehorses and 27 riding horses) were determined by ELISA. Mean (+/- SD) concentrations of CA-I and CA-II in racehorses were 1.70 +/- 0.48 and 0.94 +/- 0.13 mg/g hemoglobin (Hb), respectively. Mean concentrations of CA-I and CA-II in riding horses were 2.34 +/- 0.52 and 0.76 +/- 0.08 mg/g Hb, respectively. When the CA levels in racehorses and riding horses were compared, the CA-I level in riding horses was higher than that in racehorses (p=0.01). The CA-II level in racehorses was higher than that in riding horses (p=0.02). These data suggest that the levels of CA isozymes in erythrocytes of racehorses were influenced by chronic physical stress. The CA-I concentration in erythrocytes of 2-month-old horses was approximately 0.25 mg/g Hb. The CA-I level noticeably increased during the first year of life and approached normal adult levels by 2 years. The CA-II level decreased slightly with age, indicating different regulation of CA-I and CA-II expression during development.

The cerebellar calcification (CC) rat is a new neurodegenerative mutant with severe Purkinje cell loss and symmetrical calcifications in the cerebellar cortex manifesting ataxia: lack of coordination in body movements. In the present study, histopathological features were examined in the Purkinje cell degeneration in postnatal homozygous suckling rats without clinical signs, which were genotyped by microsatellite markers. In addition, the calcified Purkinje cells were investigated ultrastructurally and elemental analysis was performed on the deposits. Body weight of the homozygous (cc/cc) rats was already slightly lower compared with the heterozygotes (cc/+) in the neonatal stage. The degeneration of the Purkinje cells in the cc/cc rats was recognized obviously in lobules VI, VII, VIII and IX from 14 days after birth, a few days before the appearance of the ataxic behavior. The Purkinje cells in the region along the fissure between the VIII and IX lobule areas were intensely positive for periodic acid-Schiff reaction specific to glycoconjugates, and in this region, calcium depositions were weakly positive for von Kossa's stain. Electron microscopy also revealed that the calcified Purkinje cells possessed numerous electron-dense bodies containing inclusions with cystic structures such as vesicles, mitochondria and lysosomes, and these bodies were mainly composed of calcium and phosphorous. These findings suggest abnormal storage of glycoconjugates might be a trigger of Purkinje cell degeneration and serves as a matrix for accumulation of calcium phosphate in the cerebellum of CC rats.

イヌの骨格筋を材料として,CA-IIIの免疫組織化学法による組織局在と筋線維タイプとの関係について検討した。その結果,CA-IIIの免疫反応が認められる筋線維型はI型筋線維であり,II c型筋線維以外のII型筋線維には免疫反応を認めなかった。I型筋線維においては,免疫反応の有無や程度に差を認め,免疫反応陰性線維,免疫反応陽性腺維ならびに免疫反応弱陽性腺維の3つの型に分けることが出来た。結果より,CA-IIIの局在が認められる筋線維はI型筋線維であることがわかったが,全てのI型筋線維に局在は認められなかったため,CA-IIIの局在と筋線維の型分けは結ぶつかない結果となった。しかしI型筋線維におけるCA-IIIの局在が3つの型に分かれたことより,I型筋線維もいくつかの亜型に分かれることが示唆された。, Relation of immunolocalization of CA-III and muscle fiber types was studied immunohistochemically in canine skeletal muscle (M. vastus medial is). CA-III immunopositive reactions were present in type I and He fibers distinguished by use of immunostaining with Myosin Heavy Chain antibodies (slow and fast type). Type I fibers stained with CA-III antiserum classified into moderate or week immunopositive and negative immunostaining fibers. The relative frequency of moderate, weak and negative immunoreactive fibers were 21%, 28.8% and 50.2%, respectivery. All of type II fibers showed no immunopositive reaction. The results indicated CA-III could not be used as typing method of canine skeletal muscle. CA-III has been detected in type I fibers immunohistochemically in skeletal muscle of many mammals and was thought it contained in type I fibers. But this study revealed not all type I fibers contained CA-III. Physiological significance of type I fiber showed defferent immunoreaction is not known, but this results suggested type I fibers were typing in some subtypes.

Localizations of carbonic anhydrase isoenzymes (CA I, CA II and CA III) were investigated immunohistochemically in the salivary glands and intestine of mature and suckling pigs. Carbonic anhydrase isoenzymes were not detected in the salivary glands of sucklings, but were present in the adult. Bicarbonate ion in saliva might be important for the digestion of solid foods in mature pigs, but unnecessary for the digestion of milk in sucklings. Expressions of CA I and CA II were detected strongly in the large intestine of the adult and sucklings, and faintly only at duodenum in the small intestine. CA I and CA II isoenzymes in the large intestine may be involved, at least in part, in ion absorption and water metabolism during digestion and absorption of milk in suckling pigs. In addition, CA I and CA II expression in the duodenal villus enterocyte may support the process of bicarbonate absorption in the duodenum.

基礎獣医学系実習科目は獣医解剖学実習，獣医生理学実習I，獣医生理学実習II，獣医生理化学実習からなり，教養科目から専門性の高い科目へ移行する過程で，高度な知識並びに技術を習得する上で重要な実習科目となっている。これらの実習では多人数の学生を対象に効果的に実習を行う上では機器の数が不足しており，また，獣医師の職域で実際に用いられている機器と比べて，精密度や解析精度において劣っている。そのため今年度は，獣医生理学実習において使用する機器の質的，数的充実を図り，より専門性の高い実習への移行を円滑に行い，職場環境に近い実習環境を整備した。, The practices (veterinary anatomy laboratory, veterinarian physiology laboratory I, veterinarian physiology laboratory II, and veterinarian physiology chemistry laboratory) in the area of basic veterinary medicine are important subjects for acquiring knowledge and the technique by the process of shifting from the liberal arts subject to a specialized subjects for the area of applied veterinary medicine and clinical veterinary medicine. The number of equipment is insufficient to practice effectively in these practices for large number of student, and it is inferior in a analytical accuracy compared with the equipment actually used in veterinarian's occupation. In this year qualitative and quantitative improvement of the equipment used to practices in the area of veterinary physiology is carried out.

The gracile axonal dystrophy (gad) mouse is an autosomal recessive mutant that shows sensory ataxia at an early stage, followed by motor ataxia at a later stage1. Pathologically, the mutant is characterized by 'dying-back' type axonal degeneration and formation of spheroid bodies in nerve terminals2,3,4,5. Recent pathological observations have associated brain ageing and neurodegenerative diseases with progressive accumulation of ubiquitinated protein conjugates6,7. In gad mice, accumulation of amyloid β-protein and ubiquitin-positive deposits occur retrogradely along the sensory and motor nervous systems8,9. We previously reported that the gad mutation was transmitted by a gene on chromosome 5 (refs 10,11). Here we find that the gad mutation is caused by an in-frame deletion including exons 7 and 8 of Uchl1, encoding the ubiquitin carboxy-terminal hydrolase (UCH) isozyme (Uch-l1) selectively expressed in the nervous system and testis12,13,14,15. The gad allele encodes a truncated Uch-l1 lacking a segment of 42 amino acids containing a catalytic residue16. As Uch-l1 is thought to stimulate protein degradation by generating free monomeric ubiquitin16,17,18, the gad mutation appears to affect protein turnover. Our data suggest that altered function of the ubiquitin system directly causes neurodegeneration. The gad mouse provides a useful model for investigating human neurodegenerative disorders.

Pompe disease is a fatal genetic muscle disorder caused by a deficiency of acid alpha-glucosidase (GAA), a glycogen degrading lysosomal enzyme. GAA-deficient (AMD) Japanese quails exhibit progressive myopathy and cannot lift their wings, fly, or right themselves from the supine position (flip test). Six 4-wk-old acid maltase-deficient quails, with the clinical symptoms listed, were intravenously injected with 14 or 4.2 mg/kg of precursor form of recombinant human GAA or buffer alone every 2-3 d for 18 d (seven injections). On day 18, both high dose-treated birds (14 mg/kg) scored positive flip tests and flapped their wings, and one bird flew up more than 100 cm. GAA activity increased in most of the tissues examined. In heart and liver, glycogen levels dropped to normal and histopathology was normal. In pectoralis muscle, morphology was essentially normal, except for increased glycogen granules. In sharp contrast, sham-treated quail muscle had markedly increased glycogen granules, multi-vesicular autophagosomes, and inter- and intrafascicular fatty infiltrations. Low dose-treated birds (4.2 mg/kg) improved less biochemically and histopathologically than high dose birds, indicating a dose-dependent response. Additional experiment with intermediate doses and extended treatment (four birds, 5.7-9 mg/kg for 45 d) halted the progression of the disease. Our data is the first to show that an exogenous protein can target to muscle and produce muscle improvement. These data also suggest enzyme replacement with recombinant human GAA is a promising therapy for human Pompe disease.

角膜や結膜を覆う涙液の分泌母地である犬涙腺組織を対象に,分泌型炭酸脱水酵素アイソザイムCarbonic Anhydrase-VI(CA-VI)の蛋白質発現を免疫組織化学的手法を用い,ならびに遺伝子発現をRT-PCR法を用いて検討した。その結果,免疫組織化学染色では腺房を構成する腺房細胞の一部に免疫陽性反応を認めたが,導管上皮細胞には認めなかった。RT-PCR法ではイヌCA-VIと考えられる441bpの大きさの増幅産物を認めた。犬の角膜上皮にはCAの酵素活性があることが報告されており,本実験から犬の角膜上皮に存在するCAに加え,涙腺組織から分泌されているCA-VIが,眼球周囲の局所的な環境における酸塩基平衡に関与していると考えられる。, The expression of carbonic anhydrase VI protein and mRNA were investigated in canine lacrimal glands. Immunohistochemical staining of lacrimal glands was detected CA-VI protein in some aciner cells, but not in ductal cells.The presence of CA-VI mRNA in canine lacrimal glands was demonstrated by RT-PCR. RT-PCR amplification of CA-VI mRNA generated a band of the predicted 441 base pairs for CA-VI mRNA. These results indicates the canine lacrimal glands synthesize and secret CA-VI protein. It was reported that the corneal epithelia of canine has shown of CA activity, and the function of CA are transportation of CO_2 across the cornea. Therefore Althougth the physiological signification was unknown, in addition to CA in corneal epithelia, secreted CA-VI from lacrimal glands are play a role of maintenance of acid/base balance in microcircumstance around eyes.

Cloning and sequencing of the peripheral myelin protein-22 cDNA and genomic DNA from newly found Trembler mice revealed an in-frame deletion including exon IV which codes for the second (TM2) and a part of third (TM3) transmembrane domain of peripheral myelin protein-22. This mutation was distinct from those in both other allelic Trembler and Trembler-J mice, which carry point mutations within the putative transmembrane spanning regions of peripheral myelin protein-22. Inheritance was autosomal dominant. The affected mice revealed an abnormal gait, which appeared at 15-20 days of age, followed by motor and sensory ataxia, which remained throughout life. Most of the affected mice could survive more than one year. One of the most notable pathological phenotypes was a giant vacuolar formation in the sciatic nerve of homozygotes. They vary in size within the cytoplasm of Schwann cells, which failed to assemble myelin at any ages studied. Heterozygotes showed normal myelination during the early postnatal stages, followed by a segmental demyelination at an advanced stage. Vacuolar formation was not so frequent as in the homozygotes. These results suggest that the missing of transmembrane spanning region (TM2 and TM3) of peripheral myelin protein-22 may disturb a dual biological function of peripheral myelin protein-22, leading to a dysmyelination of axons and to a vacuolar formation within the cytoplasm of the Schwann cells. The latter phenotype is discussed in conjunction with the disruption of an intracellular transport system and subsequent cell death.

This study investigated whether carbonic anhydrase (CA)-VI has utility as a biomarker in swine kidney disease. Serum chemistry, histopathology, immunohistochemical staining and enzyme-linked immunosorbent assay (ELISA) analyses were performed. In the kidney of normal healthy pigs, CA-VI was localized in the epithelial cells of the renal distal straight tubules. CA-VI levels were 16 ± 35 ng/g wet tissue and 50 ± 66 ng/mL in normal pig kidney and urine, respectively, and 136 ± 173 ng/mL in the urine of pigs with kidney disease. CA-VI urinary concentration was not correlated with urinary urea nitrogen (UUN), urinary creatinine (Cre), or urinary albumin levels in pigs with kidney disease. However, UUN and Cre levels were positively correlated in the urine of pigs with kidney disease. These data suggest that urinary CA-VI may represent a biomarker for kidney disease in pigs, particularly for disorders affecting distal straight tubules.

Summary A study was made of the modification of glycoconjugates in rabbit appendix epithelium, including vacuolated cells on fetal villi, columnar absorptive cells (enterocytes) and lymphoid follicle associated epithelial (FAE) cells during the suckling, weaning and adult stages by lectin histochemistry. Sections were incubated with seven biotinyl lectins: DBA, SBA, WGA, PNA, UEA-I, ConA and RCA-I. Gradual and progressive changes were observed in the appendix epithelial glycoconjugates during postnatal development. Three groups of lectins were classified according to the lectin binding pattern. SBA, DBA and UEA-I lectins constantly stained FAE cells and enterocytes during suckling. In particular, SBA and UEA-I stained to the same extent as in weaning and adults. In contrast, the staining of DBA for FAE cells gradually decreased and almost ceased to be evident at 2 months. In the binding of PNA, FAE cells were negative or showed very slight reactivity at all developmental stages. Staining by ConA, WGA and RCA-I of FAE cells and enterocytes was virtually the same. Significant differences were not observed at any stage of development.

In the present study, we examined specific markers for taste bud cells in the mouse and the postnatal development of volatile papilla taste bud cells in ddY mice. We examined the immunoreactivity of 4 types of carbonic anhydrase isoenzymes, CA I, CA II, CA III and CA VI, as specific markers for taste bud cells, and K8.13 cytokeratin antibody as a specific marker for the lingual epithelial cells. Of the carbonic anhydrase isoenzymes, only CA III immunoreactivity was clearly detected in the spindle shaped gustatory cells. CA VI immunoreactivity was detectable in suspentacular cells. CA I and CA II antibodies did not recognize any taste bud cell specifically. K8.13 cytokeratin immunoreactivity was detected in the lingual epithelial cells, but not in taste bud cells. At 7 days after birth, the suckling phase, very small taste buds developed from the anaplastic gustatory cells. At 14 days after birth, the taste buds showed larger size than those at 7 days after birth. At 21 days birth, after the weaning phase, taste bud structure approximated the mature structure. These results demonstrate the specificity of anti-CA III and anti-CA VI for gustatory cells and suspentacular cells, respectively. These markers should be useful for an analysis of taste bud development in mice.

The hindlimbs of two orangutans and four chimpanzees were dissected, and muscle parameters (mass, fascicle length, and physiological cross-sectional area: PCSA) were determined to explore possible interspecies variation in muscle dimensions. Muscle mass and PCSA were divided by the total mass and total PCSA of the entire foot muscles for normalization. The results indicate that the pedal interosseous and the intrinsic pedal digital extensor muscles in the orangutans probably have higher capacity for force production due to their relatively larger PCSAs than in chimpanzees. Moreover, the medial components of the intrinsic muscles exhibited relatively larger mass and PCSA ratios in orangutans. The mass and PCSA ratios of the hallucal muscles were larger in chimpanzees. These differences in foot muscle dimensions of the two species suggest that the orangutan is more specialized for hook-like digital gripping without involvement of the rudimentary hallux, while the chimpanzee is adapted to hallux-assisted power gripping in arboreal locomotion.

Xylitol is used as a sugar substitute in food products. Dogs have been reported to experience lethal liver injury after accidental ingestion of xylitol. Because liver injury may be a serious consequence of canine immune-mediated reactions, antibodies produced against xylitol may attack the liver. Therefore, in the present study, we evaluated whether binding sites for xylitol antibodies are located at the liver or not. Anti-xylitol antibodies were generated by immunization of rabbits with a xylose–bovine serum albumin conjugate. Immunohistological examination showed that binding sites for the anti-xylitol antibodies were located in the hepatic arteries and the portal veins. Western blotting analyses by using a canine liver homogenate showed 4 protein bands with different molecular weights which reacted with anti-xylitol antibodies. Therefore, binding of anti-xylitol antibodies to the vessels may be the first step in an immune-mediated pathogenic response in xylitol toxicity. Further studies are necessary to determine the effects of anti-xylitol antibodies on the liver in the pathogenesis of xylitol toxicity.

Background Carbonic anhydrase (CA) of the chicken has attracted attention for a long time because it has an important role in the eggshell formation. The developmental profile of CA-II isozyme levels in chicken erythrocytes has not been determined or reported. Furthermore, the relations with CA-II in erythrocyte and egg production are not discussed. In the present study, we isolated CA-II from erythrocytes of chickens and determined age-related changes of CA-II levels in erythrocytes. Methods Chicken CA-II was purified by a combination of column chromatography. The levels of CA-II in the hemolysate of the chicken were determined using the ELISA system in blood samples from 279 female chickens, ages 1 to 93 weeks, 69 male chickens, ages 3 to 59 weeks and 52 weeks female Araucana-chickens. Results The mean concentration of CA-II in hemolysate from 1-week-old female was 50.8 ± 11.9 mg/g of Hb. The mean levels of CA-II in 25-week-old (188.1 ± 82.6 mg/g of Hb), 31-week-old (193.6 ± 69.7 mg/g of Hb) and 49-week-old (203.8 ± 123.5 mg/g of Hb) female-chickens showed the highest level of CA-II. The levels of CA-II in female WL-chickens significantly decreased at 63 week (139.0 ± 19.3 mg/g of Hb). The levels of CA-II in female WL-chicken did not change from week 63 until week 93.The mean level of CA-II in hemolysate of 3-week-old male WL-chickens was 78.3 ± 20.7 mg/g of Hb. The levels of CA-II in male WL-chickens did not show changes in the week 3 to week 59 timeframe. The mean level of CA-II in 53-week-old female Araucana-chickens was 23.4 ± 1.78 mg/g of Hb. These levels of CA-II were about 11% of those of 49-week-old female WL-chickens. Simple linear regression analysis showed significant associations between the level of CA-II and egg laying rate from 16 week-old at 63 week-old WL-chicken (p < 0.01). Conclusions Developmental changes and sexual differences of CA-II concentration in WL-chicken erythrocytes were observed. The concentration of CA-II in the erythrocyte of WL-chicken was much higher than that in Araucana-chicken (p < 0.01).

Members of the caveolin family are the main component of caveolae, and caveolin-3 is a muscle-specific protein. Caveolin-3 deficiency induces a muscular dystrophic phenotype, while its overexpression is also harmful to muscle cells. Increased caveolae were observed in chicken muscular dystrophy; however, the underlying mechanism causing the onset remains unclear. Therefore, the current study analyzes the expression of caveolin-3 and other caveola-related proteins in dystrophic chickens. Western blotting and semi-quantitative RT-PCR analysis revealed that (1) caveolin-3 is highly expressed in the damaged muscle of dystrophic chickens (7.12-fold); (2) the amount of caveolin-3 protein is regulated in posttranslational modification, since no significant increase is observed at the mRNA level (1.09-fold); and (3) the expression pattern of other caveola-related proteins is similar to that of caveolin-3. These results suggest that the accumulation of caveolin-3 protein may be associated with the causative process of chicken muscular dystrophy.

The immunohistolocalization and gene expression of carbonic anhydrase (CA) isoenzymes CA-II and CA-VI in the canine lower airways and lung were examined using specific canine CA-II and CA-VI antisera and the RT-PCR method. Laryngeal, tracheal and bronchial epithelia, serous acinar and bronchiolar secretory cells and pulmonary great alveolar cells showed immunopositive reactions to anti-CA-II and anti-CA-VI antisera. However, all mucous cells showed immunonegative reactions. The physiological roles of CA-II and CA-VI in the lower airways and lung may involve the maintenance of pH balance and the protection of mucosal surfaces against the acidic milieu.

A full-length cDNA clone of an equine carbonic anhydrase (CA)-VI was obtained from the equine parotid gland. The cDNA sequence was 1338 bp long and was predicted to encode a 319 amino acid polypeptide with a putative signal peptide of 18 amino acids. The deduced amino acid sequence of mature CA-VI showed the similarity of 70% to those of other mammalians reported. Westernblot analysis using anti-horse CA-VI peptide detected the single band in parotid gland, and the band reduced its size by treatment with N-glycosidase F. Additionally, CA-VI protein expression was confirmed in submandicular gland and weakly in liver. In contrast, RT-PCR analysis revealed signals in the digestive tract including duodenum, jejunum, ileum, cecum and colon as well as the salivary glands. In addition, certain signals were detected in testis, thyroid gland and liver, but not in nerve tissue, skeletal muscle, spleen or lymph node.

Summary While the mandibular glands usually consist of only mucous acinar cells or a combination of mucous and serous cells in other species of mammals, those of koalas were serous glands. Rabbit mono-specific polyclonal anti-canine CA-I, II, III or VI antiserum showed cross-reactivity against corresponding koala carbonic anhydrase (CA) isozymes. Although immunohistochemical reactions to CA-I, II and VI in ductal cells were moderate to strong in the tested salivary glands, no reaction or only slight reactions were observed against CA-III. In the sublingual glands, moderate immunohistochemical reactions to CA-I, II and VI were also evident in serous acinar cells and serous demilunes. However, no reactions to the tested isozymes were observed in mucous acinar cells in these glands. With the exception of the histological structure of the mandibular glands, histological features and the distributional profile of CA isozymes of the salivary glands in koalas are relatively close to results obtained from horses.

Eight forelimbs of three orangutans and four chimpanzees were dissected and the muscle mass, fascicle length and physiological cross-sectional area (PCSA) of all forelimb muscles were systematically recorded to explore possible interspecies variation in muscle dimensions. Muscle mass and PCSA were divided by the total mass and total PCSA of the entire forelimb muscles for normalization. The results indicate that the mass and PCSA ratios of the monoarticular elbow flexors (M. brachialis and M. brachioradialis) are significantly larger in orangutans. In contrast, the mass ratios of the biarticular muscles in the upper arm (the short head of M. biceps brachii and the long head of M. triceps brachii) are significantly larger in chimpanzees. For the rotator cuff muscles, the force-generating capacity of M. subscapularis is significantly larger in orangutans, whereas the opposite rotator cuff muscle, M. infraspinatus, is larger in chimpanzees. These differences in forelimb muscle dimensions of the two species may reflect functional specialization for their different positional and locomotor behaviors.

We dissected the hindlimb of a female western lowland gorilla and determined the muscle dimensions (mass, fascicle length, and physiological cross-sectional area: PCSA). Comparisons of the muscle parameters of the measured gorilla with corresponding reported human data demonstrated that the triceps surae muscles were larger and had more capacity to generate force than the other muscle groups in both species, but this tendency was more prominent in the human, probably as an adaptation to strong toe-off during bipedal walking. On the other hand, PCSAs of the extrinsic pedal digital flexors and digiti minimi muscles were larger in the western lowland gorilla, suggesting that the foot, particularly the fifth toe, has a relatively high grasping capability in the lowland gorilla.

Chicken muscular dystrophy with abnormal muscle (AM) has been studied for more than 50 years, but the gene responsible for it remains unclear. Our previous studies narrowed down the AM candidate region to approximately 1Mbp of chicken chromosome 2q containing seven genes. In this study, we performed sequence comparison and gene expression analysis to elucidate the responsible gene. One missense mutation was detected in AM candidate genes, while no remarkable alteration of expression patterns was observed. The mutation was identified in WWP1, detected only in dystrophic chickens within several tetrapods. These results suggested WWP1 is responsible for chicken muscular dystrophy.

The immunolocalization of the efferent duct and the epididymis in canine was firstly examined using an the immunohistochemical method with the canine carbonic anhydrase (CA) -I, CA-II and CA-III antisera. The efferent duct was immunonegative for all present canine CA antisera. However, some slender shaped epithelial cells in the head and body segments of the epididymal duct were intensely reacted to the CA-II antiserum. These results suggested that the CA-II might be controlled in the luminal environment in the head and body segments of the canine epididymis by the proton and bicarbonate balance for the maintenance of the spermatozoal stability and movement.