Effect ofprostaglandins E1 and E2 on hypothalamoneurohypophyseal--Neurosecretory systems of rats: a histochemical study.

PGE2 increases NSM in the neurosecretory neurons and posterior pituitary store of HNNS. It stimulates acid phosphatase and TPPase activities in HT, indicating increased synthesis of NSM. PGE2 also increases AChE and BuChE activities. PGE1 shows very little effect on NSM distribution and enzyme activities. It is concluded that PGE2 causes increased HNNS activity by stimulating AChE-mediated and Ca2+-dependent "stimulation secretion coupling mechanism".