Complex sentence: The exact mechanism by which it inhibits GnRH is poorly understood although expression of prolactin receptors (PRL-R) have been demonstrated in rat's hypothalamus, the same has not been observed in GnRH neurons.
Split into simpler sentences: The exact mechanism by which it inhibits GnRH is poorly understood. Although expression of prolactin receptors (PRL-R) have been demonstrated in rat hypothalamus, the same has not been observed in GnRH neurons.