OBJECTIVETo investigate the significance of aquaporin-1(AQP-1) and aquaporin-3(AQP-3) in the development of colorectal carcinoma.

METHODSThe expression of AQP-1 and AQP-3 was investigated using immunohistochemical staining with Streptavidin Peroxidase in tissues from colorectal adenoma (CRA, n=25), colorectal cancer (CRC, n=50), and adjacent mucosa (CRT, n=50).

RESULTSThe positive rate of AQP-1 was 64%(32/50) in CRC, significantly higher than that in CRT (38%, 19/50) and CRA(32%, 8/25)(P<0.05). The expression of AQP-1 was associated with depth of invasion and lymph node metastasis in CRC patients(P<0.05). The positive rate of AQP-3 was 56% in CRT, 44% in CRA, and 52% in CRC. There were no significant differences (P>0.05). The expression of AQP-3 was associated with age, tumor diameter, and depth of invasion (P<0.05). No significant correlation between the expression of AQP-1 and AQP-3 in CRC was shown by Spearman correlation analysis(P>0.05).

CONCLUSIONSAQP-1 expression is increased in CRC while the expression of AQP-3 is not. There is no correlation between the expression of AQP-1 and AQP-3 in CRC.

Adult ; Aged ; Aquaporin 1 ; metabolism ; Aquaporin 3 ; metabolism ; Colorectal Neoplasms ; metabolism ; Female ; Humans ; Male ; Middle Aged

OBJECTIVETo study the interaction among aquaporin1 (AQP), aquaporin2 (AQP2) and antisecretory factor( AF) , and their expression in the rat inner ear for furthur understanding of Meniere' s disease.

METHODSInner ear tissue section of six healthy male Sprague-Dawley rats was performed and Envision immunochemical staining was applied to detect the expression of AF, AQP1 and AQP2 in the rat inner ear. Vestibular and cochlear tissues of twenty healthy male Sprague-Dawley rats were dissected. Coimmunoprecipitation and Western Blot were used to specifically immunoprecipitate AF protein in the vestibular and cochlear tissues with monoclonal antibodies against AQP1 and polyclonal antibodies antibodies against AQP2 to detect the above precipitate with specific antibodies against AF.

RESULTS(1) AF was widely distributed in the inner ear, such as marginal cells of stria vascularis , five classes of spiral ligament fibrocyte , Reissner's membrane, basilar membrane, ampullar crest and so on with mild or moderate staining. In addition, round membrane was moderately or markedly stained. Positive immunostaining was found in the cochlear spiral ganglion, vestibular nerve and cochlear nerve. AQP1 was distributed in the intermediate cells in stria vascularis, type III fibrocyte of spiral ligament, basilar membrane and round membrane with moderate to marked degree of immunostaining intensity. AQP2 was mainly localized to the type II, IV, and V fibrocyte of spiral ligament, with moderate to marked degree of immunostaining intensity, round membrane was weakly stained. (2) No band was observed in the control and a single immunoreactive band of 60 000 was observed, which was equal to the molecular mass of AF.

CONCLUSIONS(1) AF, AQP1 and AQP2 have its individual specific localization in the rat inner ear, which was close to the parts of endolymph, so regulating water of the endolymph may be possible. (2) The range of localization of AF overlapped the distribution of AQP1 and AQP2. The results showed the existence of AF protein in the immunoprecipitate using co-immunoprecipitation combined with Western Blot. It suggested that the interaction between AQP1, AQP2 and AF might be possible.

Animals ; Aquaporin 1 ; metabolism ; Aquaporin 2 ; metabolism ; Cochlea ; metabolism ; Ear, Inner ; metabolism ; Male ; Neuropeptides ; metabolism ; Rats ; Rats, Sprague-Dawley

OBJECTIVETo investigate the expressions of aquaporins (AQPs) in the mouse prostatic tissue and their significance, and to provide some evidence for a deeper insight into the physiological function and regulation of AQP expressions in normal and diseased prostatic tissues.

METHODSThe mRNA expressions of AQP0 - 4 in the mouse prostatic tissue were determined by RT-PCR, and the expressions and localizations of AQP1 and AQP3 proteins were characterized by Western blot and immunohistochemistry.

RESULTSRT-PCR exhibited the mRNA expressions of AQP1 and AQP3, but not those of AQP0, AQP2 and AQP4 in the prostate tissue, while Western blot showed the expression of the AQP1 protein with the relative molecular mass (RMM) of 28 000 and those of the glycosylated and non-glycosylated AQP3 proteins with the RMM of 35 000 and 27 000, respectively. Immunohistochemistry indicated the strong expression of AQP1 in the cyst and plasma membrane of the secretary cells and that of AQP3 in the stroma cells of the prostate.

CONCLUSIONThe AQP1 and AQP3 genes were expressed in the secretary epithelia of the mouse prostate tissue, which suggests that AQP1 and AQP3 may play an important role in the secretion of prostatic fluid.

Animals ; Aquaporin 1 ; genetics ; metabolism ; Aquaporin 3 ; genetics ; metabolism ; Male ; Mice ; Mice, Inbred BALB C ; Prostate ; metabolism ; pathology

We investigated the expression of aquaporin 1 (AQP1) in tissues from canines with an inherited anomaly that causes their erythrocytes to have high K+. Northern blot analysis revealed abundant AQP1 expression in lung and kidney, though little expression was found in spleen. Using anti-C-terminus for dog AQP1, abundant expression was shown in kidney, trachea, and eye, but little expression was shown in pancreas and cerebrum, indicating that AQP1 expression in canine tissues is similar to that noted in other mammals.
Animals ; Aquaporin 1/*metabolism ; Blotting, Northern ; Dogs ; Erythrocytes/*chemistry ; Immunoblotting ; Potassium/*analysis ; Viscera/metabolism

OBJECTIVETo study the ultrastructural localization of aquaporin 1 (AQP1) in the endolymphatic sac (ES) of the mouse inner ear and explore the function of the AQP1 in ES.

METHODSThe cellular localization of AQP1 in ES of the mouse inner ear was investigated by immunocytochemistry. The ultrastructural localization of AQP1 in the mouse inner ear was performed by immunogold electron microscopy which is characterized as cryoprotection and high sensitivity.

RESULTSIn the ES, strong AQP1 labeling was observed in the sub-epithelial connective tissue. Fibroblasts of sub-epithelial connective tissue of the ES present densely labeling of gold particles. But the epithelial cells of the ES were devoid of labeling. AQP1 was localized on the cell processes of the fibrocytes.

CONCLUSIONSAQP1 in the ES may play an important role in absorbing water and regulate the balance of fluid and ion in the inner ear.

Animals ; Aquaporin 1 ; metabolism ; Endolymphatic Sac ; metabolism ; ultrastructure ; Mice ; Mice, Inbred Strains ; Microscopy, Electron

Aquaporins (AQPs) are expressed in myocardium and the implication of AQPs in myocardial water balance has been suggested. We investigated the expression patterns of AQP subtypes in normal myocardium and their changes in the process of edema formation and cardiac dysfunction following myocardial infarction (MI). Immunostaining demonstrated abundant expression of AQP1, AQP4, and AQP6 in normal mouse heart; AQP1 in blood vessels and cardiac myocytes, AQP4 exclusively on the intercalated discs between cardiac myocytes and AQP6 inside the myocytes. However, neither AQP7 nor AQP9 proteins were expressed in CD1 mouse myocardium. Echocardiography revealed that cardiac function was reduced at 1 week and recovered at 4 weeks after MI, whereas myocardial water content determined by wet-to-dry weight ratio increased at 1 week and rather reduced below the normal at 4 weeks. The expression of cardiac AQPs was up-regulated in MI-induced groups compared with sham-operated control group, but their time-dependent patterns were different. The time course of AQP4 expression coincided with that of myocardial edema and cardiac dysfunction following MI. However, expression of both AQP1 and AQP6 increased persistently up to 4 weeks. Our findings suggest a different role for cardiac AQPs in the formation and reabsorption of myocardial edema after MI.
Animals ; Aquaporin 1/metabolism ; Aquaporin 4/metabolism ; Aquaporin 6/metabolism ; Aquaporins/*metabolism ; Edema/pathology ; Immunohistochemistry ; Mice ; Muscle Cells/metabolism ; Myocardial Infarction/*metabolism/pathology/ultrasonography ; Myocardium/metabolism/pathology ; Time Factors

To evaluate the effect of dexamethasone on the expression of aquaporin-1 (AQP-1) in cultured bovine trabecular meshwork cells, bovine trabecular meshwork cells were cultured in vitro and reproduced to the third and the fourth generation, then treated with dexamethasone at the concentrations of 5, 25, 50, 250 microg/L respectively for 7 days. Immunohistochemical technique-supervision method was employed to measure, and image analysis system to analyze the expression of AQP-1 in normal cultured bovine trabecular meshwork cells and those treated with dexamethasone. In normal bovine trabecular meshwork cells, the grayscale of AQP-1 positive staining was 167.94 +/- 1.18, while it was 168.92 +/- 0.91, 176.72 +/- 1.80, 180.64 +/- 1.31, 185.64 +/- 1.58 in cells treated with 5, 25, 50, 250 microg/L concentrations of dexamethasone. When the concentration of dexamethasone was higher than 25 microg/L, the expression of AQP-1 was significantly inhibited (P < 0.05). The regulation of AQP-1 expression by dexamethasone in cultured bovine trabecular meshwork cells in vitro may be one of causes that retard the aqueous outflow in glucocorticoid- induced glaucoma.
Aquaporin 1/*biosynthesis ; Aquaporin 1/genetics ; Cells, Cultured ; Depression, Chemical ; Dexamethasone/*pharmacology ; Dose-Response Relationship, Drug ; Immunohistochemistry ; Trabecular Meshwork/cytology ; Trabecular Meshwork/*metabolism

OBJECTIVES: To observe the changes of expression of aquaporin-1（AQP-1） and AQP-4 in drowned and postmortem immersed rats' lungs. METHODS: Thirty healthy male Wistar rats were randomly divided into drowning group, postmortem immersion group and cervical dislocation group. The morphological changes of rats' lungs were observed using HE staining. The mRNA and protein expressions of AQP-1 and AQP-4 in rats' lungs were detected by real-time PCR, immunohistochemistry and Western blotting, respectively. RESULTS: The results of immunohistochemistry and the Western blotting showed that the protein expression of AQP-1 of the drowning group was higher than the postmortem immersion group and the cervical dislocation group （P<0.05）. The result of immunohistochemistry showed that the protein expression of AQP-4 of the drowning group was higher than the postmortem immersion group and the cervical dislocation group （P<0.05） while no difference were detected among the three of them by Western blotting （P>0.05）. The mRNA expressions of AQP-1 and AQP-4 in rats' lungs of the drowning group was significantly higher than the postmortem immersion group （P<0.05）. CONCLUSIONS The increase of mRNA and protein expressions of AQP-1 and AQP-4 in lungs of rats with cute lung injury of the drowning group would be useful for differentiating vital drowning from postmortem immersion.
Animals ; Aquaporin 1/metabolism* ; Aquaporin 4/metabolism* ; Autopsy ; Blotting, Western ; Drowning ; Immunohistochemistry ; Lung/metabolism* ; Male ; RNA, Messenger ; Rats ; Rats, Sprague-Dawley ; Rats, Wistar ; Real-Time Polymerase Chain Reaction

OBJECTIVE: To determine the expression of water channel 1 protein in the lung of drown rat and that of after death thrown into the water. METHODS: Immunohistochemical method was used and the computer image analysis was conducted to detect the distribution of AQP1. RESULTS: The positive expression of AQP1 was seen in the capillary endotheliocyte of the interstitial and around bronchi and in the alveolar endothelial cells. The value of intergrated optical density was statistical significant. CONCLUSION It suggests that AQP1 is one of sensitive signs to distinguish ante-mortem and postmortem immersion.
Animals ; Aquaporin 1 ; Aquaporins/metabolism* ; Drowning/metabolism* ; Endothelial Cells/metabolism* ; Immunohistochemistry ; Lung/metabolism* ; Membrane Proteins/metabolism* ; Rats ; Rats, Sprague-Dawley

OBJECTIVETo determine if aquaporin1 (AQP1) and aquaporin5 (AQP5) are expressed in the alveolar capillary membrane in rats. Moreover, to investigate the alteration of AQP1 and AQP5 in acute injured lungs.

METHODSThe distribution of AQP1 and AQP5 in alveolar capillary membrane were investigated by immunohistochemistry and immunoelectron microscopy with affinity-purified antibodies to human AQP1 and AQP5. To study the possibility that alveolar capillary membrane AQP1 and AQP5 undergo altered regulation, we established a rat model using alveolar instillation of lipopolysaccharide (LPS).

RESULTSImmunolabelling showed AQP1 was stained primarily in the microvascular endotheli a of normal lungs, while AQP5 was expressed in type I pneumocytes. Immunohisto chemical analysis showed a significant decrease in the expression of AQP1 and AQP5 in injured lungs at 4h-48h after LPS instillation. AQP1 protein was resumed partly at 24h after LPS instillation and steroid administration, whereas AQP5 was unchanged.

CONCLUSIONThe decreased expressions of AQP1 and AQP5 in injured lungs suggest that both of them may play a role in abnormal fluid transportation.

Animals ; Aquaporin 1 ; Aquaporin 5 ; Aquaporins ; analysis ; Immunohistochemistry ; Lipopolysaccharides ; toxicity ; Lung ; metabolism ; Male ; Membrane Proteins ; Microscopy, Immunoelectron ; Rats ; Rats, Sprague-Dawley ; Respiratory Distress Syndrome, Adult ; metabolism ; pathology