Acute effects of unilateral sectioning the superior ovarian nerve of rats with unilateral ovariectomy on ovarian hormones (progesterone, testosterone and estradiol) levels vary during the estrous cycle

Abstract

The present study analyzed the participation of the left and right superior ovarian nerves (SON) in regulating progesterone, testosterone, and estradiol serum levels in unilaterally ovariectomized rats on each day of the estrous cycle. For this purpose, ovarian hormone concentrations in serum were measured in animals with either sham-surgery, unilateral ovariectomy (ULO), unilateral sectioning of the SON, or sectioning of the SON innervation of the in situ ovary in rats with ULO.This investigation results show that the right and left ovaries have different capacities to maintain normal hormone levels, that such capacity varies during the estrous cycle, and that it depends on the integrity of the SON innervation. In rats with only one ovary, the effects of ovarian denervation on hormone levels varied according to which ovary remained in situ, the specific hormone, and the day of the estrous cycle when treatment was performed. Present results support the idea that the ovaries send and receive neural information that is processed in the central nervous system and we propose that this information participates in controlling the secretion of gonadotropins related to the regulation of ovarian functions.

Effects on steroid hormones secretion resulting from the acute stimulation of sectioning the superior ovarian nerve to pre-pubertal rats

“…As previously proposed for adult animals [19,23], the results obtained in the present study suggest that the SON innervation arriving to the ovaries of pre-pubertal rats plays a role regulating P 4 , T, and E 2 secretion. However, there is a difference between pre-pubertal and adult animals in their hormone secretion ability, suggesting that in the pre-pubertal stage of the animal the neural, and even perhaps the hormone regulation system, is not mature.…”

“…However, there is a difference between pre-pubertal and adult animals in their hormone secretion ability, suggesting that in the pre-pubertal stage of the animal the neural, and even perhaps the hormone regulation system, is not mature. Another possibility that may explain such difference is the time of the day when the animals were treated (9:00–11:00 in pre-pubertal animals and 13:00 h in adult) [23]. …”

“…The lower levels of E 2 observed in animals sacrificed 60 min after SON sectioning suggests that in the pre-pubertal rat the left SON regulates E 2 secretion in a stimulatory way. Kagitani et al, [15] suggested that the SON inhibits ovarian E 2 secretion, while Flores et al [23] showed that the participation of the SON on steroid hormone secretion by the ovaries depends on the day of the estrous cycle. Without discarding that the right ovary has a greater capacity to secrete E 2 [22], these differences could be attributed to the maturity stage of the rat.…”

The Ovarian Innervation Participates in the Regulation of Ovarian Functions

“…The effects of unilateral or bilateral laparotomy on progesterone, testosterone and estradiol serum levels depend on the day of the cycle and the surgical approach (dorsal or ventral) used [84][85][86][87][88][89].…”

In vitro<b> </b>Autoradiographic Analysis of Regional Changes in Estrogen Receptor Alpha in the Brains of Cycling Female Rats

“…The contribution of circulating T to the control of female reproductive function is of particular interest since previous studies have shown that circulating levels of this steroid in females are higher than those of E 2 and fluctuate several-fold across the ovarian cycle [9,10]. In female primates, circulating androgens contribute significantly to the expression of sexual behavior and the regulation of reproductive function [11,12].…”