Abstract
Background: The metanephric glomeruli develop from the metanephric blastema and ureteric bud. The nephron anlage undergoes multiple differentiation stages, fusion and invagination that lead to the formation of nephron. Objectives: To describe the morphological changes and transformations that lead to formation of metanephric permanent glomerulus during peri-natal period. Method: The study was performed on albino rat as a model for mammalian embryonic development. Embryos of 20-22 days of gestation and neonatal litters were investigated for renal development. The specimens were double fixed, plastic embedded and semi-thin sections stained with methylene blue were examined. Results: It was shown that glomerular development continues during late pre-natal days and first week post-natally. Maturity was attended by the end of the 7th post-natal day. The developing glomerulus passes through the stages describes as vesicle, comma, S-shaped, double comma, elongation and ovale stage to become finally mature. Conclusion: The metanephric glomerulus passes through sequential, multi-stage, pleomorphic development during peri-natal period. These features should be considered during evaluation of kidney during this period.