Evaluation of the PATHFAST Chemiluminescent Enzyme Immunoassay for Measuring Progesterone in Whole Blood and Serum of Mares.
Evaluation of a new chemiluminescent enzyme immunoassay, the PATHFAST assay system (PATHFAST), for measurement of circulating progesterone in mares was performed. Five mares at the mid-luteal stage were administrated a single i.m. injection of prostaglandin F2α analog (PGF2α; cloprostenol 250 μg/ml), and then blood samples were collected from the jugular vein at 0, 15, 30 and 45 min, at one-hour intervals until 24 and at 48 hr via a catheter in the jugular vein. To monitor the physiological changes in circulating progesterone in mares after induced luteolysis, concentrations of progesterone in whole blood and serum samples were measured by PATHFAST. In addition, concentrations of progesterone in serum samples measured by PATHFAST were compared with those measured by radioimmunoassay (RIA) and enzyme immunoassay (EIA). Using PATHFAST, the serum concentrations of progesterone in mares correlated highly with those of whole blood samples (r=0.9672, n=88). The serum concentrations of progesterone as measured by PATHFAST correlated well with RIA (r=0.9654, n=88) and EIA (r=0.9323, n=112). An abrupt decline in circulating progesterone in whole blood samples was observed within 2 hr (50%), followed by a gradual decline until 48 hr later. The results for progesterone in whole blood samples correlated highly with those in serum samples, and the declining pattern paralleled that of the serum samples. These results demonstrated that PATHFAST is useful in the equine clinic as an accurate diagnostic tool for rapid assay of progesterone within 26 min, using unextracted whole blood.
Shadai Corporation, Hokkaido 059-1432, Japan.
Yuko
Y
Toishi
Shadai Corporation, Hokkaido 059-1432, Japan.
Nobuo
N
Tsunoda
Shadai Corporation, Hokkaido 059-1432, Japan.
Masaaki
M
Tagami
Shadai Corporation, Hokkaido 059-1432, Japan.
Hiromitsu
H
Hashimoto
Shadai Corporation, Hokkaido 059-1432, Japan.
Fumiki
F
Kato
Shadai Corporation, Hokkaido 059-1432, Japan.
Tsukasa
T
Suzuki
Laboratory of Veterinary Physiology, Cooperative Department of Veterinary Medicine, Faculty of Agriculture, Tokyo University of Agriculture and Technology, Tokyo 183-8509, Japan ; Department of Basic Veterinary Science, United Graduate School of Veterinary Sciences, Gifu University, Gifu 501-1193, Japan.
Kentaro
K
Nagaoka
Laboratory of Veterinary Physiology, Cooperative Department of Veterinary Medicine, Faculty of Agriculture, Tokyo University of Agriculture and Technology, Tokyo 183-8509, Japan ; Department of Basic Veterinary Science, United Graduate School of Veterinary Sciences, Gifu University, Gifu 501-1193, Japan.
Gen
G
Watanabe
Laboratory of Reproductive Physiology, Graduate School of Environmental and Life Science, Okayama University, Okayama 700-8530, Japan.
Shota
S
Tokuyama
Laboratory of Reproductive Physiology, Graduate School of Environmental and Life Science, Okayama University, Okayama 700-8530, Japan.
Kiyoshi
K
Okuda
Shadai Corporation, Hokkaido 059-1432, Japan.
Kazuyoshi
K
Taya
PATHFAST; enzyme immunoassay; horses, PATHFAST; progesterone; radioimmunoassay