Leptin is a 16 KDa protein, consists of 167 amino acid residues. It has many
functions including angiogenesis. Leptin either induces angiogenesis itself or
influences the levels of other angiogenic factors. The aim of the present investigation
was to study the effect of leptin on the levels of the angiogenic factors: vascular
endothelial growth factor (VEGF) and thymidine phosphorylase (TP) enzyme activity
in prepubertal female albino rats. Twenty prebubertal female albino rats were divided
randomly into two groups; 1st group (group I); rats were injected intraperitoneally
with saline alone and considered as control group. The 2nd group (group II); its rats
were daily intraperitoneally injected with leptin (recombinant rat leptin (L5073),
Sigma-Aldrich) in a dose of 3 μg/g. body weight in 100 μl saline for 10 days.
Obtained results revealed that leptin increased significantly the serum levels of both
VEGF levels and TP activity. In addition, there was a positive correlation between
VEGF levels and TP activity.