Artículo de revista
In vivo blockade of ovarian sympathetic activity by neosaxitoxin prevents polycystic ovary in rats
Fecha
2020Registro en:
Journal of Endrocrinology 244 (2020): 523-533
10.1530/JOE-19-0545
Autor
Campos, Miguel del
Lagos Wilson, Néstor
Lara Peñaloza, Hernán
Institución
Resumen
A high sympathetic tone is observed in the development and maintenance of the polycystic ovary (PCO)
phenotype in rats. Neosaxitoxin (NeoSTX) specifically blocks neuronal voltage-dependent Na+
channels, and we studied the capacity of NeoSTX administered into the ovary to block sympathetic
nerves and PCO phenotype that is induced by estradiol valerate (EV). The toxin was administered with a
minipump inserted into the bursal cavity using two protocols: (1) the same day as EV administration and
(2) 30 days after EV to block the final step of cyst development and maintenance of the condition. We
studied the estrous cycling activity, follicular morphology, steroid plasma levels, and norepinephrine
concentration. NeoSTX administered together with EV decreased NA intraovarian levels that were
induced by EV, increased the number of corpora lutea, decreased the number of follicular cyst found
after EV administration, and decreased the previously increased testosterone plasma levels induced by
the PCO phenotype. Estrous cycling activity also recovered. NeoSTX applied after 30 days of EV
administration showed near recovery of ovary function, suggesting that there is a specific window in
which follicular development could be protected from cystic development. In addition, plasma
testosterone levels decreased while those of progesterone increased. Our data strongly suggest that
chronic inhibition of sympathetic nerves by a locally applied long-lasting toxin is a new tool to manage
the polycystic phenotype in the rat and could be applied to other mammals depending on sympathetic
nerve activity.