Immunohistochemistry of the Bovine Secretory Carbonic Anhydrase Isozyme (CA-VI) in Bovine Alimentary Canal and Major Salivary Glands

Abstract

ABSTRACT. 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. KEY WORDS: bovine digestive organs, CA-VI, immunohistochemical localization.J. Vet. Med. Sci. 68(2): 131-135, 2006 Carbonic anhydrase isozyme-VI (CA-VI) is a unique secretory type CA isozyme. It was initially discovered and purified from ovine saliva [7], and then rat saliva [6,21], human saliva [13,20,22,25] and bovine saliva [5]. Fernley et al. [8] examined sheep CA-VI in 18 different tissues from sheep using biochemical analysis. They observed an immunoreactive signal for CA-VI only in parotid and mandibular glands, which suggested that CA-VI increased buffering capacity in the oral cavity. Some studies have identified the acinar cells of salivary glands as the origin of CA-VI in several species [5,8,21,22,25]. These studies have shown that CA-VI was present in acinar cells of the mammalian parotid and mandibular glands, from where CA-VI is secreted into the saliva. However, CA-VI expression in other segments of the alimentary canal has received little information and the precise physiological role of bovine CA-VI has never been revealed. The present study examines the immunohistochemical expression of CA-VI in bovine alimentary canal and in major salivary glands, and conjectures the function of CA-VI in the bovine digestive organs. MATERIALS AND METHODSTissue: Three adult Holstein cows were used in the present study. Small tissue blocks were prepared for microscopic observation. Samples were cut from the parotid, mandibular, and monostomatic sublingual glands, from cervical to thoracic segments of the esophagus, rumen, reticulum, omasum, abomasum, duodenum, jejunum, ileum, cecum, colon and rectum. The samples were immediately fixed in Bouin's solution, and then sliced into 3 µm-thick sections. CA-VI antibody:We purified CA-VI from bovine saliva as described previously [5]. A rabbit polyclonal antibody has been raised against purified bovine CA-VI and specific immunity to bovine CA-VI has been confirmed [5]. Briefly, the antibody against purified bovine CA-VI was produced in the rabbit. Rabbits were injected initially with 1 mg of purified CA-VI emulsified with an equal volume of Freund's complete adjuvant, followed by a weekly booster injection of a fixed amount of the enzyme for 5 weeks. The rabbits were bled via the auricular vein 10 days following the last injection. The specificity of the antiserum was confirmed by the doubl...

Association of polymorphisms in the carbonic anhydrase 6 gene with salivary buffer capacity, dental plaque pH, and caries index in children aged 7–9 years

“…1,2 CAVI was shown to be expressed in the lacrimal glands, 3 lowers airways and lungs of rats, 4 in the mouse nasal gland, 5 in the lingual serous glands of von Ebner in humans, 6 in human and rat mammary gland and present in milk, 7 as well as in the lining epithelial cells of large intestine, stomach, and esophagus. 8 The importance of CAVI is evidenced by its involvement in several malfunctions. Decreased secretion of salivary CAVI has been associated with loss of taste (hypogeusia) and smell (hyposmia) and distorted taste (dysgeusia) and smell (dysosmia).…”

Distribution of Carbonic Anhydrase in Digestive Tract of Pond Loach (Misgurnus anguilicaudatus)

“…CA is a peptide with zinc (Zn) atom and several isoenzymes of CA family are isolated and characterized among animal species [1,10,12,17]. In 1952, the function of CA was firstly characterized by Janowitz [11] that it is associated with HCl excretion in gastric juice in mammals [11].…”

“…Although the exact functional difference of CA in the vascular endothelium and red cells in esophagus in comparison to the stomach and intestine is still unclear, it might associate with the effect of pH balance and epithelial development. It has been documented that the secretion of CA-VI from saliva and esophageal secretions may be useful in the maintenance of pH and ion balance at the upper digestive tract [12]. On the other hand, the effect of CA may play a role in the epithelial development in the intestine [12].…”

“…It has been documented that the secretion of CA-VI from saliva and esophageal secretions may be useful in the maintenance of pH and ion balance at the upper digestive tract [12]. On the other hand, the effect of CA may play a role in the epithelial development in the intestine [12].…”

“…CA can be detected by various methods such as the fluorescence antibody staining [9], immunohistochemistry [1,3,10,12], colorimetry [30] and pressure reducing method [16,18]. Based on previous studies, Kurata's method [15] is the most convenient with reasonable specificity and sensitivity.…”