Changes in phospholipase A2 activity of the rabbit ampullary epithelium by ovarian steroids.
Phospholipase A2 (EC 3.1.1.4) activity of the ampullary epithelium from rabbit oviducts was compared in the presence of various ovarian steroids to assess how they could modulate prostaglandins (PG) biosynthesis in the oviduct. The phospholipase A2 (PLA2) activity of the cells from ovariectomized rabbits (control) was 190.8 +/- 9.8 pmol/min/mg. The PLA2 activity of the cells from progesterone-treated rabbits was 156.0 +/- 41.8 pmol/min/mg and was not significantly different from the control activity. However, the PLA2 activity of the cells from the estrogen-treated rabbits was 233.5 +/- 29.0 pmol/min/mg, which was significantly higher than the control activity (p < 0.05). On the other hand, the PLA2 activity of the cells from progesterone-treated rabbits after being primed with estrogen was 116.3 +/- 25.9 pmol/min/mg, which was significantly lower than the control activity (p < 0.01). These results suggest that the effects on PLA2 activity of ovarian steroids could regulate the local production of PG which plays a role in both smooth muscle contractility and ciliary activity.
Morishita
T
T
Department of Gynecology and Obstetrics, Faculty of Medicine, Kyushu University, Fukuoka, Japan.
Nozaki
M
M
Sano
M
M
Yokoyama
M
M
Nakamura
G
G
Nakano
H
H
D019326:17-alpha-Hydroxyprogesterone; D000818:Animals; D004848:Epithelium / Q000187:drug effects / Q000502:physiology; D004958:Estradiol / Q000031:analogs & derivatives* / Q000494:pharmacology; D005260:Female; D006908:Hydroxyprogesterones / Q000494:pharmacology*; D010052:Ovariectomy; D010057:Oviducts / Q000187:drug effects* / Q000502:physiology; D010741:Phospholipases A / Q000187:drug effects* / Q000502:physiology; D054467:Phospholipases A2; D011817:Rabbits
D006908:Hydroxyprogesterones; D004958:Estradiol; D019326:17-alpha-Hydroxyprogesterone; D010741:Phospholipases A; D054467:Phospholipases A2