Disease relevance of Ca2

• 0. We conclude that CA II is essential not only in bone resorption but also in osteoclast differentiation [1].
• However, in acute renal failure, with leaking tubular cells, CA II was excreted into the urine [2].

High impact information on Ca2

• The membrane-bound CA isoforms IV, IX, XII, and XIV and cytosolic CA II and the vanilloid receptor 1 (TRPV1) were expressed in duodenum and stomach [3].
• Such changes are mediated by enhanced d -myo-inositol 1,4,5-triphosphate/Ca 2+ /protein kinase C signaling and the consequent inhibition of the adenosine 3',5'-cyclic monophosphate/protein kinase A/Src/extracellular signal-regulated kinase 1/2 cascade [4].
• Thus, the distribution of CA IV is quite distinct from that of CA II; it corresponds with the localization of an isoenzyme(s) that did not stain with antibodies against CA II but that was revealed by histochemical-staining procedures [5].
• Inhibition of NHE activity by amiloride inhibits regeneration of alkaline microdomains after cytoplasmic acidification, whereas the inhibition of CAII activity with ethoxyzolamide inhibits acidification of dendrites [6].
• The carbonic anhydrase II gene, whose transcription is enhanced by 1, 25-dihydroxyvitamin D3 (1,25-(OH)2D3), encodes an important enzyme in bone-resorbing cells derived from the fusion of monocytic progenitors [7].

Biological context of Ca2

• Nucleotide sequence of a cDNA encoding rat brain carbonic anhydrase II and its deduced amino acid sequence [8].
• The rat carbonic anhydrase II gene was characterized and found to be approximately 15.5 kb in length and to contain 7 exons and 6 introns [9].
• All intron/exon junction and branch point sequences conform to consensus sequences, and the overall rat CA II genomic structure appears to be conserved upon comparison with mouse, human, and chicken CA II genes [9].
• Characterization of the rat carbonic anhydrase II gene structure: sequence analysis of the 5' flanking region and 3' UTR [9].
• In contrast, the hepatocyte-like cells colonizing the mesentery showed the phenotype of mature hepatocytes, including an abundant glycogen storage and a lack of alpha-fetoprotein and carbonic anhydrase II expressions [10].

Anatomical context of Ca2

• Immunohistochemical co-expression of carbonic anhydrase II with Kv1.4 and TRPV1 in rat small-diameter trigeminal ganglion neurons [11].
• In both processes, however, the crucial role of CA II is at least partially due to the effect on the osteoclast pHi regulation [1].
• To study how CA II, which is crucial in proton generation in mature osteoclasts, influences the osteoclast differentiation process we performed rat bone marrow cultures [1].
• CA-II activity was unaffected by treatment of the cultures with a method reported to remove oligodendrocytes [12].
• The immunoelectronmicroscopy showed that CA II is expressed in their epithelial cells only [13].

Associations of Ca2 with chemical compounds

• The turnover number kcat for hydration of CO2 was 6.5 X 10(4) s-1 and the Michaelis constant was 4.2 mM at pH 7.5 and 25 degrees C, values which are equal to the steady state constants for red cell carbonic anhydrase II from the rat [14].
• The hepatocyte-like cells from the subcutaneous implantation site expressed mixed phenotypes of both hepatocyte and ductal cell, including the expression of alpha-fetoprotein, tyrosine amino-transferase, gamma-glutamyl transpeptidase, carbonic anhydrase II, and cytokeratin 19 [10].
• Fluorescein-labeled cDNA probes and a confocal laser scanning microscope were used to study the localization of VPL and CA II mRNAs in situ in osteoclasts and other bone-derived cells attached to bovine bone slices in vitro [15].
• In normal rats estrogen increased CA II concentration of dorsal prostate but there was no change in lateral prostate [13].
• Androgen regulates the expression of CAII at messenger RNA level, but the responses of CAII to testosterone are opposite in dorsal and lateral prostate [13].

Physical interactions of Ca2

• It is further concluded that the cytosolic carbonic anhydrase (CA II) and the membrane-bound carbonic anhydrase (CA IV) are not involved in glucose synthesis from pyruvate [16].

Regulatory relationships of Ca2

• No astrocytes expressing glial fibrillary acidic protein or oligodendrocytes expressing carbonic anhydrase II were found to co-express Kir6.2 mRNA [17].

Other interactions of Ca2

• These results show that not only CA-II, but also CA-III isozyme is represented in the central nervous system and carbonic anhydrase activity may correlate with metabolic and immunological changes of microglial cells [18].
• Using immunolabeling and confocal microscopy, we found reduction in expression of two choroidal proteins, carbonic anhydrase II and aquaporin 1, involved in CSF secretion [19].
• Detection of estrogen receptor alpha, carbonic anhydrase II and tartrate-resistant acid phosphatase mRNAs in putative mononuclear osteoclast precursor cells of neonatal rats by fluorescence in situ hybridization [20].
• In addition, calcitonin reduced the number of CA II mRNA-positive mononuclear precursor cells [21].
• However, as distributions of ezrin and carbonic anhydrase II remained altered in both flight and suspended animals after readaptation to Earth gravity, it was concluded that choroidal structures and functions were not completely restored, even after 2 days in Earth's gravity [22].

Analytical, diagnostic and therapeutic context of Ca2

• Northern blot analysis reveals that the 1.7 kb rat CA II mRNA is abundantly expressed in adult male brain and kidney, while negligible amounts are detected in heart and liver [9].
• We have studied the effect of immobilization on the expression of two proteins believed to have a major functional role in osteoclasts, the proteolipid subunit of vacuolar H(+)-ATPase (VPL) and carbonic anhydrase II (CA II) [15].
• The cell type primarily responsible for CA II expression in the lung was identified by immunohistochemistry as the alveolar type II pneumocyte [23].
• Estimation of glial contamination of synaptosomal-mitochondrial fractions of rat brain by radioimmunoassay of carbonic anhydrase (CA II) [24].
• Castration of the rats decreased the concentration of CA II in lateral prostate but increased in dorsal prostate [13].

References