Dysphoric milk ejection reflex to nipple/areolar stimulation, thoughts of the baby or of breastfeeding, or overfull breasts, travels through both brain and bloodstream, causing emotional changes in the brain and the release of milk in the breast. Prolactin, released in a gradual wave that peaks after the beginning of a feeding, is responsible for continued milk production. Dopamine inhibits the release of prolactin, so dopamine levels must drop in order for prolactin levels to rise. Some speculate that the necessary dopamine drop is similar to (and timed with) the oxytocin spike – a sort of negative image – but that in D-MER mothers it
KCNE2 less milk (hypothyroidism of the dams impairs milk ejection), the milk they receive is deficient in T, and they themselves cannot adequately transport iodide into the thyroid. "Kcne2"-/- pups exhibit stunted growth, alopecia, cardiomegaly and reduced cardiac ejection fraction, all of which are alleviated by thyroid hormone supplementation of pups or dams. Surrogating "Kcne2"-/- pups with "Kcne2"+/+ dams also alleviates these phenotypes, highlighting the influence of maternal genotype in this case. As observed for hERG mutations, KCNE2 loss-of-function mutations are associated with inherited LQTS, and hERG-KCNE2 channels carrying the mutations show reduced activity compared to wild-type channels. In addition, some