KNDy neuron and Seasonal reproduction

During anestus, how does E2 suppress kisspeptin and GnRH?

E2 increases dopamine and dynorphin from A15 neurons to decrease kisspeptin, thus decreasing GnRH

During estrus, how does KNDy neurons work?

• E2 reduces pulse amplitude by decreasing kisspeptin

• P4 increases dynorphin (inhibitory)

When are A15 dopaminergic neurons activated?

During anestrus, inhibitory photoperiod acting via melatonin activates A15 dopaminergic

What is the role of dopamine in anestrus E2 negative feedback

• KNDy neurons contain dopamine receptors which mediates the actions of A15 neurons, decreasing kisspeptin and GnRH

During anestrous, E2 increases the ___________ containing the D2 receptor

% of KNDy neurons

The suppression of kisspeptin release from A15 neurons thus a reduction in GNRH pulse frequency ultimately does what?

Ultimately inhibits LH release and preventing ovulation

During estrus, what does E2 and P4 do?

Follicular: E2 inhibits pulse amplitude (modestly) via a decrease in kisspeptin.

Luteal: P4 inhibits pulse frequency via an increase in dynorphin

In anestrus, what does E2 do?

E2 increased dopamine release from A15 neurons a that (innervate KNDy neurons) to inhibit kisspeptin and thus GnRH