Long-term maintenance of reaggregated hypothalamic cultures developed from embryonic rat hypothalamus: prostaglandin release during synaptogenesis in vitro.

Hypothalamic aggregate cultures were developed from hypothalami taken from rat embryos at 17-19 days gestation. The aggregate cultures exhibited a prominent morphological differentiation during 3-4 weeks in culture. The fine structure of the synapses formed in the aggregates resembled synapses in tha adult animal. During synaptogenesis the aggregates spontaneously release prostaglandin E2 (PGE2). The amount of PGE2 released in the media was reversed upon the morphological differentiation of the hypothalamic cultures. Media containing a higher PGE2 concentration increased the extracellular prolactin accumulation in monolayer cultures developed from adult rat hypophysis.