Immunohistochemical detection of estrogen receptor alpha in articular chondrocytes from cows, pigs and humans: in situ and in vitro results

Clinical observations suggest that estrogens are involved in the pathogenes is of postmenopausal osteoarthritis, but only little is known about the inf luence of these hormones on articular cartilage cells. The effect of estrad iol is mediated by estrogen receptors alpha and beta. The goal of the prese nt study was to search for estrogen receptor alpha in articular tissue from cows, pigs and humans by immunohistochemistry to form a basis for in vitro studies. In addition, we also tried to detect estrogen receptor alpha in c ultivated articular chondrocytes from cows and bulls under certain culture conditions. Estrogen receptor alpha is detected by the use of antibody 13H2 in articular chondrocytes from cows, bulls, pigs and humans. Chondrocytes are physiologically exposed to reduced oxygen tension. In isolated articula r chondrocytes from cows and bulls incubated either with 21% O-2 or With 5% O-2 positive cells were also found. These positive results therefore encou rage testing the influence of estradiol on cultivated articular cartilage c ells in these species under different culture conditions.