Influence of perfusates of tetanized donor slices on the induction of long-term potentiation in recipient slices.

A perfusate collected from donor slices of the olfactory cortex of the brain of rats during tetanization of the lateral olfactory tract (100 imp/sec, 30 sec) induced prolonged changes in the amplitudes of various components of the focal potentials (FP) in recipient slices. When the perfusates are divided in relation to the reactions arising in the donor slices into three types, "potentiated," "depressive," and "nonpotentiated," the reactions of the recipient slices prove to be diverse. The potentiated perfusate induced the development of depression. The depressive induced potentiation. The reactions of the recipient slices to the nonpotentiated perfusate were indeterminate. The data obtained suggest the secretion of active substances during the electrical tetanization of donor slices. These factors are capable of inducing reactions in the recipient slices which the donor slices had "experienced."