) serum levels in rats with unilateral or bilateral sectioning of the superior ovarian nerve (SON). Mean ± S.E.M. of P4 levels in serum. Left (L-LAP), right (R-LAP), bilateral (B-LAP) laparotomy, with sectioning of the left superior ovarian nerve (L-SON), right (R-SON) or bilateral (B-SON) performed to 32 days of age. Animals were sacrificed 30 or 60 minutes after surgery. p<0.05 vs. control (MANOVA followed by a Tukey′s test).*p<0.05 vs. its respective LAP group (Student′s t-test). ♦ indicating vs. control group.