Immunohistolocalization and Gene Expression of Secretory Carbonic Anhydrase Isoenzyme CA-VI in Canine Nasal Cavity

Abstract

ABSTRACT. 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. KEY WORDS: canine nasal cavity, CA-VI, immunohistochemistry, mRNA.

Nasal ciliary beating controlled by carbonic anhydrase IV and Na+/HCO3- co-transport under an extremely low CO2 condition (air)

“…Here, we used c-hBECs, which express CAs except CAIV and bicarbonate transporters, similarly to c-hNECs. A previous study showed that CAIV expression is lower in the trachea and lower airways than that in the larynx [25]. S0859 and DIDS did not decrease CBF and pH i in c-hBECs, indicating that the activity of NBC is low.…”

Immunohistochemical Localization and Gene Expression of Carbonic Anhydrase Isoenzymes CA-II and CA-VI in Canine Lower Airways and Lung

“…The immunohistochemical distribution of CA-II has been determined in the respiratory system of humans [15] and rats [2], while that of CA-VI has been reported for mice [7] and rats [8]. Recently, canine CA-VI was detected in the upper respiratory tract, in particular, in the nasal cavity [16]. Thus, in the present study we examined the canine lower airways and lung to clarify the distribution of the CAs throughout the whole canine respiratory tract.…”

“…They were immediately fixed in neutralized 10% formalin or Bouin's solution and cut into 4-m-thick sections. Immunohistochemistry was performed as previously described [16]. The working dilution of anti-CA-II was 1:1000 and that of anti-CA-VI was 1:100.…”

“…We used the Vectastain Elite avidin-biotin-peroxidase complex kit (ABC-POD reagent kit; Vector, Burlingame, CA, U.S.A.) for detection of the first antibody and developed color with diaminobenzidine (DAB) according to the protocol supplied by the manufacturer. Isolation of total RNA and synthesis of cDNA from mucosa samples and lung were performed as previously described [16]. The primer sequences for canine CA-II (XM_855990) were 5'-CAGCAACCTGATGGACTG-GCTG-3' and 5'-GCCTGCTGTGCAGTGGCTGAG-3', generating a 358-bp fragment.…”

Immunohistolocalization and Gene Expression of the Carbonic Anhydrase Isoenzymes (CA‐II and CA‐VI) in Glands Associated with the Canine Lacrimal Apparatus

“…Physiologically, CA‐VI in the oral cavity is thought to enhance the buffering capacity of the oral cavity (Kivela et al., 1999b). Secretorial CA‐VI has also been detected in the mammary gland in cows (Ichihara et al., 2003), respiratory tract in rats (Leinonen et al., 2004) and nasal cavity in dogs (Sugiura et al., 2008). Immunohistolocalization and in situ hybridization histochemistry have identified acinar cells of the lacrimal gland in rats and sheep as the origin of CA‐VI (Ogawa et al., 1995, 2002).…”