* To whom correspondence should be addressed.
Received July 25, 1997
Most biological functions of unsaturated fatty acids are due to their ability to act as second messengers or modulators of activities of functionally important proteins; these functions are not related to oxidative metabolism of unsaturated fatty acids. These acids regulate the activity of phospholipases, ion channels, ATPases, G-proteins, and protein kinases; they also modulate the phosphoinositide and sphingomyelin cycles, the transfer of hormonal information, and gene transcription. The great diversity of effects of unsaturated fatty acids and their presence at the earliest stages of evolution suggest for these bioregulators a system-forming role in the living body.
KEY WORDS: phospholipases, sphingomyelin cycle, ion channels, second messengers, hormonal signaling, regulation of transcription