[Effect of arachidonic acid on the secretion of milk caseins in vitro]

Arachidonic acid increases milk casein secretion in mammary gland slices. This stimulation is similar to prolactin stimulation. Aspirin, a prostaglandin-synthetase inhibitor, has no effect on prolactin or on arachidonic acid stimulation. Prostaglandin PGF2 alpha does not modify casein secretion. Therefore arachidonic acid stimulates casein secretion by metabolic products different from prostaglandins.