Histopathological and Ultrastructural Changes Induced in the Renal Cortex of Male Rats by Gibberellic Acid

Abstract
Objectives: The present study was designed to evaluate the toxic effect of GA3 on the renal cortex of rats and to assess the possibility of recovery after GA3 withdrawal.

Materials and Methods: Rats (n = 50) were classified into 5 groups: group 1 (control) received no treatment, animals belonging to group 2 and group 3 were respectively given GA3 at doses of 100 and 200part per million (ppm) daily for eight weeks in drinking water. Animals of recovery groups (group 4 and group 5) were remained for eight weeks without treatment after receiving 100 and 200 ppm of GA3 in drinking water for eight weeks respectively. Rats were dissected; kidney samples were collected and processed for histopathological and ultrastructural studies.

Results: The renal cortex of GA3-treated rats exhibited its apparent toxic effect on renal corpuscles and renal convoluted tubules associated with fibrosis. These observations confirmed by the ultrastructure examination of renal cortical tissues. The Renal cortex from animals treated with 200 ppm GA3 revealed more severe structural changes. However, eight weeks of GA3 withdrawing has resulted in some regression of the pathological changes.

Conclusion: GA3 has dose-dependent toxic effects. While stop giving of GA3 for eight weeks revealed incomplete recovery of its harmful effects. Therefore, exposure to GA3 should be limited.

Keywords: Plant Growth Regulators, Gibberellic Acid Toxicity, Renal Cortex, Ultrastructure, Rats