Abstract
Our study was designed to determine the spatiotemporal pattern of different lectins in developing rat kidneys postnatally, which was unprecedented before. We used immunohistochemistry to examine the localization of three different lectins, Concanavalin (Con A), Wheat germ agglutinin (WGA), and Peanut agglutinin (PNA), in rat kidneys of both sexes at neonatal day 1 and postnatal 1, 2, and 8 weeks. The intensity of the Con A lectin decreased with age, from intense at birth to moderate in the proximal convoluted tubules (PCT) and absent in the distal convoluted tubules (DCT) by 8 weeks. Renal corpuscles showed intense reactions to Con A in immature glomeruli at birth and intense reactivity in podocytes at 8 weeks of age in rats. Con A was intense in collecting tubules (CT) and collecting ducts (CD) of all ages. The intensity of the WGA lectin increased with age, from no reaction at birth to moderate reactions in PCT and DCT at 8 weeks. WGA was intense in immature glomeruli at birth, but only in podocytes at 8 weeks. The CT and CD showed mild to moderate reactions to WGA in all ages of rat kidneys. The PNA lectin in PCT decreased in intensity with age, from a moderate reaction at birth to no reaction at 2 and 8 weeks. The PNA lectin in DCT increased in intensity with age, from a moderate reaction at birth to an intense reaction at 8 weeks. The PNA in the renal corpuscle decreased in intensity with age, from a moderate reaction in immature glomeruli at birth to no reaction at other ages. The CT and CD showed an intense reaction to PNA in all ages of rat kidneys. We conclude that there were differences in the lectin distribution and intensity between developing and adult rat kidneys, and this variation may be related to the function of each lectin.

Key words: Rat; Lectins;Con A; WGA; PNA; Kidney