Enhancement of rat hippocampal long-term potentiation by 17β-estradiol involves mitogen-activated protein kinase-dependent and -independent components

Abstract

To investigate if estrogen modulates long-term potentiation (LTP) via mitogen-activated protein kinase (MAPK) activation, in vitro hippocampal slices were used to induce LTP through extracellular field recordings. Slices perfused with 17β-estradiol exhibited a significant enhancement of LTP (224±19%) compared with LTP in control slices (157±9%). In the presence of PD098059, 17β-estradiol still produced a significant magnitude of LTP (131±7%), revealing the existence of p-MAPK-independent LTP mediated by 17β-estradiol. Immunocytochemistry showed that 17β-estradiol promoted a transient increase in nuclear translocation of p-MAPK. 17β-estradiol induced the extracellular proteolysis of neural ce..