In the above-listed article, the description of doses for estrogen administration were inadvertently incorrect. Below are the corrected paragraphs with the appropriate doses, with the first paragraph to replace the first paragraph on page 979 and the second paragraph to replace the third paragraph on page 981.
Estradiol replacement.
Subgroups of male and OVX rats received intrascapular subcutaneous injections of 2.0 μg 17 β-estradiol-3-benzoate (Sigma Chemical, St. Louis, MO) in 100 μl sesame oil every 4 days between 0900 and 0930 h for 1 month to simulate estrus cycles; control injections were 100 μl sesame oil (Sigma Chemical). Dosing began 1 week after the surgeries. The dose of 2.0 μg estradiol in 100 μl reportedly produces plasma estradiol levels similar to peak levels occurring during the ovarian cycle in intact rats (7) and, when administered over an extended period of time, normalizes body weight and daily food intake of OVX rats (7). For central estradiol administration, a smaller volume (1 μl) of the same concentration of estradiol (2 μg/100 μl oil or 0.02 μg centrally) was injected i3vt every 4th day for 1 month. Control animals were injected with the same volume of the vehicle sesame oil.
Central estradiol replacement increases sensitivity to i3vt leptin.
The dose of estradiol administered into the brain (0.02 μg) did not cause changes in vaginal cytology and did not increase plasma estradiol (estradiol levels were assayed following central injections on the day that most closely represents proestrus [Table 2]), implying that it had little or no systemic effect (the same dose, when administered peripherally instead of i3vt, also did not influence food intake, body fat distribution, vaginal cytology, or plasma estradiol levels; data not shown). Following 1 month of i3vt estradiol, body weight was significantly reduced in OVX females relative to vehicle-injected OVX controls (Table 2). Additionally, OVX females receiving central estradiol were more sensitive to i3vt leptin than vehicle-treated controls, their level of leptin sensitivity matching that of intact cycling females (Table 1).
