Although several studies have shown that glucocorticoids exert diuretic effects in animals and humans, the underlying mechanism responsible for the acute diuretic effect remains obscure. Here we examined the mechanism in terms of gene-expression. We observed that glucocorticoids, including dexamethasone (Dex) and prednisolone (PSL), acutely induced diuresis in rats in a dose-dependent manner.
View Article and Find Full Text PDFThe role of aquaporin proteins (AQPs) in tumor biology has attracted attention over the past 20 years. However, the expression profiles of AQPs in canine sebaceous gland tumors remain obscure. This study was performed to clarify the expression of AQP1, 3, 5, the most studied AQPs in tumor biology, in sebaceous adenoma and sebaceous epithelioma.
View Article and Find Full Text PDFMouse HORMAD1 is a phospho-protein involved in multiple functions during meiotic prophase I. To obtain insight into the significance of its phosphorylation, we generated phospho-specific antibodies against two serine residues, Ser307 and Ser378, representing each of two serine clusters in mouse HORMAD1. The Ser307 phosphorylation is detectable from early leptotene substage in both wild-type and Spo11 spermatocytes, indicating that Ser307 is a primary and SPO11-independent phosphorylation site.
View Article and Find Full Text PDFAquaporin-5 (AQP5) water channel, transmembrane protein 16A (TMEM16A) Ca-activated Cl channel, and Na-K-2Cl cotransporter (NKCC1) are membrane proteins on salivary gland acinar cells that function in watery saliva secretion. We examined their expression changes in rat parotid glands under reduced mastication. Rats were either fed regular chow as a control group, fasted for 48 hr or fed a liquid diet for 48 hr or 1 week to reduce mastication.
View Article and Find Full Text PDFAquaporins (AQPs) are water channel proteins, and the expression of AQPs in carcinoma cells has received much attention over the last 15 years. In the veterinary field, however, little is known about the expression of AQPs. In the present study using immunohistochemistry, we examined the expression of AQP1, AQP3, and AQP5 in canine mammary gland carcinomas.
View Article and Find Full Text PDFBackground/aim: Tears secreted from the lacrimal gland are essential for preserving the ocular surface. Thus, dysfunction of the lacrimal gland in Sjögren's syndrome (SS) can lead to dry eye, resulting in a reduced quality of life. We previously reported that blueberry 'leaf' water extract prevents lacrimal hyposecretion in male non-obese diabetic (NOD) mice in a SS-like model.
View Article and Find Full Text PDFBackground: Systemic sclerosis (SSc) is a connective tissue disorder characterized by the development of fibrosis in the skin and internal organs. Increasing evidence suggests that mesenchymal stem cells (MSCs) can be used to a treatment for fibrotic diseases. Recent studies have demonstrated that some of the biological effects of MSCs are due to the secretion of exosomes.
View Article and Find Full Text PDFPachychoroid spectrum diseases have been described as a new clinical entity within the spectrum of macular disorders. "Pachychoroid" is defined as choroidal thickening associated with dilated outer choroidal vessels often showing retinal pigment epithelium (RPE) degeneration. Although various clinical studies on the pachychoroid spectrum diseases have been conducted, the pathophysiology of pachychoroid has yet to be fully elucidated.
View Article and Find Full Text PDFBiochem Biophys Res Commun
April 2020
Circadian rhythms are a fundamental biological phenomena that control various physiological functions. The suprachiasmatic nucleus (SCN) is a master clock that integrates various peripheral clocks. Recently, the choroid plexus (CP) was reported to be one such peripheral clock, a circadian oscillator that might conversely affect the SCN.
View Article and Find Full Text PDFNihon Yakurigaku Zasshi
November 2019
Immunofluorescence microscopy is a powerful method for analysis of the subcellular localization of the protein of interest. The use of fluorescence is very effective for multiple labeling and for higher magnification observation with a laser confocal microscope. A basic protocol of the immunofluorescent staining in cultured cells with some useful suggestions are introduced in the present paper.
View Article and Find Full Text PDFRadiation therapy for head and neck cancer frequently causes salivary gland dysfunction. Pilocarpine is a clinically approved and effective drug that induces saliva secretion, thereby keeping the oral mucosa moist and reducing discomfort in patients, but the effect is transient. We expected that this drug also has beneficial long-term effects that maintain the integrity of salivary glands by reducing, for instance, apoptosis.
View Article and Find Full Text PDFThe DBA/2-FG pcy (pcy) mouse is a model of human nephronophthisis, a recessive cystic kidney disease. Renal expression of aquaporin-2 (AQP2), a water channel protein, has been shown to be altered in pcy mice. However, the relationship between the renal expression and its release in urinary extracellular vesicles (uEV-AQP2), which account for most urinary AQP2, in pcy mice has remained largely unknown.
View Article and Find Full Text PDFAcute kidney injury (AKI) is an important risk factor for the development of chronic kidney disease (CKD), and an alteration in renal water handling has been observed during the transition of AKI to CKD. Urinary exosomal release of aquaporin-1 (AQP1) and AQP2, important proteins for renal water handling, has recently been reported to predict their levels of renal expression. Therefore, we examined the patterns of urinary exosomal release of AQP1 and AQP2, and the exosomal marker proteins tumor susceptibility 101 protein (TSG101) and ALG-2 interacting protein X (Alix), in the acute and chronic phases following induction of AKI by renal bilateral ischemia/reperfusion (I/R) in rats.
View Article and Find Full Text PDFThe membrane water channel aquaporin (AQP) family is composed of 13 isoforms in mammals, eight of which are reportedly expressed in the kidney: AQP1, 2, 3, 4, 6, 7, 8, and 11. These isoforms are differentially expressed along the renal tubules and collecting ducts. AQP1 and 7 are distributed in the proximal tubules, whereas AQP2, 3, and 4 occur in the collecting duct system.
View Article and Find Full Text PDFThe Dlg1 gene encodes a member of the MAGUK protein family involved in the polarization of epithelial cells. Null mutant mice for the Dlg1 gene (Dlg1-/- mice) exhibit respiratory failure and cyanosis, and die soon after birth. However, the cause of this neonatal lethality has not been determined.
View Article and Find Full Text PDFVasopressin is the main hormone that regulates water conservation in mammals and one of its major targets is the principal cells in the renal collecting duct. Vasopressin increases the apical water permeability of principal cells, mediated by apical accumulation of aquaporin-2 (AQP2), a water channel protein, thus facilitating water reabsorption by the kidney. The mechanisms underlying the accumulation of AQP2 in response to vasopressin include vesicular trafficking from intracellular storage vesicles expressing AQP2 within several tens of minutes (short-term regulation) and protein expression of AQP2 over a period of hours to days (long-term regulation).
View Article and Find Full Text PDFBackground: The aim of the present study was to clarify the anatomy between the left triangular ligament (LTL) and the appendix fibrosa hepatis (AFH) in order not to sever the AFH when dissecting the LTL.
Methods: Totals of 43 and 27 cadaveric livers were examined macroscopically and histologically, respectively.
Results: The LTL attached itself to the diaphragmatic surface of the AFH through almost all lengths of the AFH.
Neurons co-expressing kisspeptin, neurokinin B (NKB), and dynorphin in the hypothalamic arcuate nucleus, named KNDy neurons, are directly affected by sex hormones, and are well known for regulating the secretion of gonadotropin-releasing hormone. However, recent studies have shown that KNDy neurons also project and terminate to tuberoinfundibular dopaminergic (TIDA) neurons, suggesting a role in prolactin secretion. Moreover, there is a possibility that other neurosecretory dopaminergic neurons regulating prolactin secretion, such as periventricular hypophyseal dopaminergic (PHDA) neurons, may also be innervated by KNDy neurons.
View Article and Find Full Text PDFAquaporins (AQPs), a family of water channel proteins expressed in various cells and tissues, serve as physiological pathways of water and small solute transport. Articular cartilage is avascular tissue with unique biomechanical structure, a major component of which is "water". Our objective is to investigate the immunolocalization and expression pattern changes of AQPs in articular cartilage with normal and early degenerative regions in the human knee joint, which is the joint most commonly involved in osteoarthritis (OA).
View Article and Find Full Text PDFIn the present study, we examined the changes in the morphofunction of astrocytes in rat hippocampus under different circulating corticosteroid conditions by immunohistochemistry analysis of glial fibrillary acidic protein (GFAP) and ultra-high-voltage electron microscopy. Each GFAP-immunoreactive cell showed a hypertrophic appearance with well-developed thicker fibrous processes, and the number and the density of GFAP-immunoreactive cells were increased 4 weeks after adrenalectomy, whereas the changes were restored to the sham-control level with corticosterone replacement. The morphometric changes were observed in particular around the pyramidal neurons of CA1 and in the subgranular layer of dentate gyrus.
View Article and Find Full Text PDFActa Histochem Cytochem
October 2012
Aims: Aquaporin3 (AQP3) is distributed widely in mammalian tissues and plays an important role in fluid homeostasis. The aim of this study was to investigate the pattern of expression of AQP3 in a variety of human neoplastic tissues and to explore its diagnostic implications.
Methods And Results: We studied 798 neoplastic tissues using immunohistochemistry with anti-AQP3 antibody.
Background: Aquaporin3 (AQP3) and Aquaporin4 (AQP4) play a major role in transcellular and transepithelial water movement as water channel membrane proteins. Little is known of their expression and significance in human thyroid tissues. Thus, we examined the expression of AQP3 and AQP4 in normal, hyperplastic and neoplastic thyroid tissues in conjunction with human thyroid cancer cell lines.
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