JNK activity following olfactory bulb lesions: JNK activation was measured by Western blot assay using phospho-specific (p) antibodies, and pJNK2 expression was normalized to total JNK2 protein. JNK1 was constitutively active in all cases. Virtually no pJNK2 was seen in the sham-injected controls in either control or estrogen-replaced animals. Bulb lesions significantly increased pJNK2 at 6 h after the lesion. At 24 h, pJNK2 levels were still elevated in the control-replaced (OVX) lesioned animals but significantly attenuated in the estrogen-treated (OVX+E) lesioned group. Anti-p75NTR reversed the effects of estrogen on pJNK2 activation at 24 h, although it had no effect on the control-pellet group. Two representative examples are shown from each treatment condition in the Western blot images. Histogram bars represent means+SEM for the entire group (n = 6). Sham: Sham lesion, Lesion+Vehicle: NMDA injection with pre immune serum, Lesion+Anti p75: NMDA injections with anti-p75NTR antibodies. *:p < 0.05.