Such a positive mark had a grainy appearance and was evidenced in both small and large luteal cells
[H.sub.2][O.sub.2] or lipid peroxide have been found to accumulate in the CL during luteal regression [33,34], while antioxidant vitamins have been reported to be effective against reactive oxygen species in cultured rat luteal cells
Aten, "Evidence that hydrogen peroxide blocks hormone-sensitive cholesterol transport into mitochondria of rat luteal cells
," Endocrinology, vol.
Cell apoptosis is closely associated with the initiation of follicular atresia and luteal cell
Moreover, increased lifespan of luteal cells
has been demonstrated in the GCs of [Pten.sup.-/-] mice (19).
It has been documented before that TNF[alpha] together with IFN[gamma] can serve as mediators of luteolytic actions of [PGF.sub.2[alpha]] via inhibiting P4 production and stimulating apoptosis of the cultured bovine luteal cells
It was reported that injections of GnRH at or near the estrus increased the proportion of large luteal cells
in the CL on day 10 of cycle resulting in more peripheral progesterone concentration and increased pregnancy rates in repeat breeding cows (Mee et al., 1993).
In vitro studies in luteal cells
have shown that nicotine causes luteal insufficiency by inhibiting progesterone release (3).
Thus, the increase in the antioxidative capacity of the luteal cells
prevents the oxidative stress even though there is an increase of ROS assuring that CL could complete its physiological cycle.
Reichert LE, Effect of prolactin on LH receptor in rat luteal cells
. Endocrinol 98 (1976) 1005.
Constitutive steroidogenesis in ovine large luteal cells
may be mediated by tonically active protein kinase A.