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Arachidonic acid (AA) samples and mixtures of arachidonic acid - cholesterol (AA-C) were manufactured and subjected to external electric cw or pulsatory optical laser fields. The polarizing microscope showed a pseudohomeotropic smectic C texture for AA at 10 degree(s)C and smectic C textures with fibers for mixtures AA-C at room temperature. The dependences I equals I(U) at t degree(s)C equals const. and I equals I(t) at U equals const., t being time, showed that samples are dielectrics with a weak conduction (I approximately equals 10-9 A, U equals 0 - 40V). Pure acid samples present an electric hysteresis which disappears when cholesterol is added. The current occurred when the electric field is applied, decreases in time, and tends to a constant value. When the temperature was 19 degree(s)C, a cw focussed laser radiation from a He-Ne laser ((lambda) equals 632.8 nm, P equals 20 mW) determined a lenselike effect in AA, but no effect in mixtures. At the same temperature, the samples were crossed by some green pulses ((lambda) equals 532 nm, (tau) equals 200 microsecond(s) ) furnished by an experimental setup containing a Nd3+ glass laser and a KDP crystal for the second harmonic generation. The shape and extension of the pulse in the time domain, displayed on a sampling oscilloscope, are some indications of the cholesterol percentage.
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