No abstract

We report the effects that sectioning the superior ovarian nerve of infantile female rats has on their follicular development at different ages before puberty. Compared with the control group, sham-operated animals showed a significant decrease in the number of measured follicles in right and left ovaries, although no difference in the follicular atresia ratio was observed. Animals with a sectioned left superior ovarian nerve (SON), killed 12 days after surgery had a significant increase in the number of follicles in the ovaries. Most of the follicles were atretic. Sectioning the right SON induced contrasting effects in the ovaries of animals killed 4 and 16 days after surgery. Rats with a denervated (right) ovary showed a decrease in the number of follicles and a greater number of atretic follicles compared with the control group, whereas the innervated (left) ovary showed an increase in measured follicles compared with the control group.Bilateral sectioning had no apparent effect on the total number of follicles measured, although an increased number of atretic follicles in both ovaries was observed. Animals with a unilateral section of the SON, killed 8 and 12 days after surgery, showed a decrease in serum concentrations of estradiol. In turn, animals killed 16 days after surgery showed a significant increase in estradiol and a decrease in the progesterone serum concentration.These results suggest that sympathetic innervation of the ovary via the SON has a stimulatory role in the regulation and differentiation of follicular growth.

There is evidence that sensory innervation plays a role regulating ovarian functions, including fertility.Since sensory denervation by means of capsaicin in newborn female rats results in a lower response togonadotropins, the present study analyzed the effects that sensory denervation by means of capsaicin in neonatal rats has on the concentration of monoamines in the anterior(AH) and medium (MH) hypothalamus, and on steroid hormone levels in serum. Groups of newborn female rats were injected subcutaneously with capsaicin and killed at 10, 20, and 30 days of age and on the first vaginal estrous.The concentrations of noradrenaline, dopamine, serotonin(5-HT), and their metabolites in the AH and MH were measured using HPLC, and the levels of estradiol (E),progesterone (P), testosterone (T), FSH, and luteinizing hormone using radioimmunoanalysis. The results show thatat 20 days of age, capsaicin-treated rats have lowernoradrenergic and serotonergic activities in the AH, and that the dopaminergic activity was lower in the MH. These results suggest that the sensorial system connections within the monoaminergic systems of the AH and MH are different.Capsaicin-treated animals had lower T, E, and P levels than in the control group, suggesting that the lower activity in the AH monoaminergic system and lower hormonesecretion could be explained by the blockade of information mediated by the sensory innervation (probably substance P), mainly between the ovary and the AH.