GH1 and acromegaly: Many studies demonstrated that GHRH antagonists can also strongly inhibit the stimulatory activity of exogenous and endogenous GHRH on GH secretion, suggesting that they could be used for the treatment of diseases caused by excessive production of GHRH or GH, such as acromegaly and diabetic retinopathy [20,21,22,23,24,25,26,27].