If you read my entire post you will see that unlike in humans, TRH does not influence prolactin release in sheep. (1)
I suggested two different theories that might explain how tren could elevate prolactin, if in fact it really does. One involved progesterone receptor binding, and the other (in case tren is not a progesterone receptor agonist) involved TRH elevation.
(1) Endocrinol 1988 Apr;117(1):115-22
Release of prolactin is independent of the secretion of thyrotrophin-releasing hormone into hypophysial portal blood of sheep.
Thomas GB, Cummins JT, Yao B, Gordon K, Clarke IJ.
Medical Research Centre, Prince Henry's Hospital, Melbourne, Australia.