Measurement of Erythrocyte Carbonic Anhydrase Isozymes (CA-I and CA-II) in Racehorses and Riding Horses

Abstract

ABSTRACT. Equine carbonic anhydrase isozymes (CA-I and CA-II) were purified from erythrocytes by several column chromatography. Polyclonal anti-CA-I and anti-CA-II sera were produced in rabbits. Sensitive competitive enzyme-linked immunosorbent assays (ELISA) were established to determine the developmental changes in CA-I and CA-II levels in equine erythrocytes. Concentrations of CA-I and CA-II in erythrocytes from 150 clinically normal thoroughbreds (123 racehorses and 27 riding horses) were determined by ELISA. Mean (± SD) concentrations of CA-I and CA-II in racehorses were 1.70 ± 0.48 and 0.94 ± 0.13 mg/g hemoglobin (Hb), respectively. Mean concentrations of CA-I and CA-II in riding horses were 2.34 ± 0.52 and 0.76 ± 0.08 mg/g Hb, respectively. When the CA levels in racehorses and riding horses were compared, the CA-I level in riding horses was higher than that in racehorses (p=0.01). The CA-II level in racehorses was higher than that in riding horses (p=0.02). These data suggest that the levels of CA isozymes in erythrocytes of racehorses were influenced by chronic physical stress. The CA-I concentration in erythrocytes of 2-month-old horses was approximately 0.25 mg/g Hb. The CA-I level noticeably increased during the first year of life and approached normal adult levels by 2 years. The CA-II level decreased slightly with age, indicating different regulation of CA-I and CA-II expression during development. KEY WORDS: carbonic anhydrase, equine, ELISA, erythrocyte.

Antipsychotic agents screened as human carbonic anhydrase I and II inhibitors

“…It is difficult to study the factors and conditions that affect CA activity because standard CA activity assays have serious limitations. Therefore, estimate of the CA-I and CA-II level in erythrocytes are complicated by the pronounced differences in enzymatic activity of CA-I and CA-II (Nishita et al, 2005).…”

Morphine Inhibits Erythrocyte Carbonic Anhydrase in Vitro and in Vivo

“…Therefore, estimate of the CA-I and CA-II level in erythrocytes are complicated by the pronounced differences in enzymatic activity of CA-I and CA-II. 26) Given the importance of CA in pH regulation in most tissues, the effects of increasing concentration of morphine administration on human erythrocyte HCA-I and HCA-II isozymes were undertaken in this study. Thus, HCA-I and HCA-II were purified by Sepharose 4B-L-tyrosine-sulfanylamide affinity chromatography ( Table 1).…”

Measurement of Carbonic Anhydrase I and II Isozymes in Feces as a Marker of Occult Blood in Horses with Intestinal Tract Bleeding

“…CA-I and CA-II were detected using rabbit antiserum to equine CA-I or CA-II; this antiserum had been previously produced in our laboratory [10]. After the membranes were incubated with the primary antibody, they were incubated with peroxidase-conjugated goat anti-rabbit IgG (Kirkegaard & Perry Laboratories, Gaithersburg, MD, USA).…”

“…Equine erythrocytes contain 2 CA isozymes, CA-I and CA-II [3, 10], and only CA-II is found in equine digestive tracts [14]. Here, we determined the concentrations of CA-I and CA-II in fecal samples of horses using enzyme-linked immunosorbent assay (ELISA), and evaluated their usefulness as markers of the presence of occult intestinal blood.…”