TY - JOUR
T1 - Expression of activities of two 20α-hydroxysteroid dehydrogenase isozymes in rat corpora lutea
AU - Seong, H. H.
AU - Shiota, K.
AU - Noda, K.
AU - Ogura, A.
AU - Asano, T.
AU - Takahashi, M.
PY - 1992
Y1 - 1992
N2 - The rat ovary contains two isozymes of 20α-hydroxysteroid dehydrogenase (HSD-1 and HSD-2). In this study, the expression of activity of each isozyme was investigated in ovaries that contained a single generation of corpora lutea during pseudopregnancy. This condition was induced by cervical stimulation in rats that had been rendered anovulatory by housing them in a continuously lit environment. The total activity of cytosolic 20α-HSD was lower in the ovaries of these pseudopregnant rats than in ovaries containing multiple generations of corpora lutea. In normal pseudopregnancy, HSD-1 activity was low on days 5 and 9 and increased markedly on day 15, whereas HSD-2 was lower than HSD-1 and did not vary throughout pseudopregnancy. However, on days 5 and 9 of continuous-light pseudopregnancy, low activity of HSD-1 only was detected; by day 15, HSD-1 activity had increased sixfold and HSD-2 activity could be detected. Immunohistochemical methods using a specific antibody recognizing both HSD-1 and HSD-2 revealed that the number of 20α-HSD-positive luteal cells increased by day 15. Thus, the increase in total enzyme activity and appearance of HSD-2 activity observed at late pseudopregnancy was accompanied by an increase in the number of 20α-HSD-positive luteal cells.
AB - The rat ovary contains two isozymes of 20α-hydroxysteroid dehydrogenase (HSD-1 and HSD-2). In this study, the expression of activity of each isozyme was investigated in ovaries that contained a single generation of corpora lutea during pseudopregnancy. This condition was induced by cervical stimulation in rats that had been rendered anovulatory by housing them in a continuously lit environment. The total activity of cytosolic 20α-HSD was lower in the ovaries of these pseudopregnant rats than in ovaries containing multiple generations of corpora lutea. In normal pseudopregnancy, HSD-1 activity was low on days 5 and 9 and increased markedly on day 15, whereas HSD-2 was lower than HSD-1 and did not vary throughout pseudopregnancy. However, on days 5 and 9 of continuous-light pseudopregnancy, low activity of HSD-1 only was detected; by day 15, HSD-1 activity had increased sixfold and HSD-2 activity could be detected. Immunohistochemical methods using a specific antibody recognizing both HSD-1 and HSD-2 revealed that the number of 20α-HSD-positive luteal cells increased by day 15. Thus, the increase in total enzyme activity and appearance of HSD-2 activity observed at late pseudopregnancy was accompanied by an increase in the number of 20α-HSD-positive luteal cells.
KW - 20α-hydroxysteroid dehydrogenase
KW - Corpus luteum
KW - Pseudopregnancy
KW - Rat
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M3 - Article
C2 - 1339838
AN - SCOPUS:0027052304
VL - 96
SP - 573
EP - 580
JO - Journal of Reproduction and Fertility
JF - Journal of Reproduction and Fertility
SN - 0022-4251
IS - 2
ER -