A Comparative study on Prenatal and Postnatal changes in the Histoarchitecture of Mesentric lymph node in Laboratory Animals

Abstract

A comparative light microscopic study on the mesentric lymph node in prenatal and postnatal age groups of mice, rat and guinea pig was carried out in the present study. The lymph node is a critical cross road for encounters between the antigen presenting cells, antigenic substances from lymph and lymphocytes recruited into lymph nodes from the blood. The completely formed mesentric lymph node could be observed in the embryos of late pregnancy in guinea pigs. In the postnatal age groups, the mesentric lymph node consisted of a connective tissue capsule which varied in thickness as age advanced. The parenchyma was made up of cortex and medulla in all the age groups of the three species studied. The former had an outer and inner zone. Subcapsular sinuses were well developed. Nodules of different sizes could be observed in the outer cortex in all the species studied. Germinal centres could be recorded in the nodules of 12 month-old animals of all the species. The post capillary venules were observed in the inner cortex.