Corticoliberin (CRF) activity of the rat neurohypophysis

Corticoliberin (CRF) activity of the rat stalk-median eminence region (SME) and neural lobe of the pituitary (NL) was tested in vitro using cultured cells of anterior pituitary. The activity of NL was found to be more than 50% lower than that of SME. The parallelism of dose-response curves suggests that corticotropin releasing substances originating from NL and SME may be qualitatively identical. Thus, neurosecretory cells producing corticoliberin seem to form a continuous neurohemal system consisting of the median eminence, the stalk of the neural lobe.