Endocrine Abstracts

Ovarian function in mammals is regulated by gonadotropins and by sympathetic nervous system. Norepinephrine (NE) is one of the major neurotransmitters present in the fibres innervating the gonad and regulates follicular development and ovarian steroids release. Surgical section of the sympathetic fibres partially decreased the release of NE as compared with non-denervated rats. The remnant release capability supposes the existence of an intraovarian compartment able to incorporate and release NE independent of the sympathetic innervation. To study one of these compartments, we used fresh isolated rat granulosa cells and observe that they incorporate and release ³HNE in response to a depolarizing stimulus. These cells are immunoreactive for the dopamine transporter (DAT), and cocaine, a selective inhibitor of DAT, blocks the norepinephrine incorporation. In contrast to granulosa cells, luteal cells presented a weak immunoreactivity to DAT and a diminished capability for incorporate and release norepinephrine. This data provide information for a role of granulosa cells in the control of intraovarian norepinephrine homeostasis and possibly to the ovarian function.

Supported by: Fondecyt 1050765, PG 63/2004