Discipline: Veterinary Medicine
The influence of the submandibular salivary glands on the morphology of the non-lactating mammary gland in rat was examined by determining the effect of total surgical removal of the submandibular salivary gland (total submandibular sialoadenectomy) on this gland’s histologic features. A total of 60 sexually mature female Sprague-Dawley rats were divided into three experimental groups: intact (n=20), sham-operated (n=20) and sialoadenectomized (n=20). Sixty days post surgery, all rats under the three experimental groups were sacrificed and mammary glands were collected per animal. The mammary glands were fixed and processed using the routine paraffin technique. Tissue sections of the glands were stained with H & E, Masson’s Trichrome and Weigert’s stains and examined under the light microscope to describe the structure of the mammary gland’s stroma and parenchyma. The secretory alveoli were counted and the mean (±SD) were subjected to statistical analysis using the one-way ANOVA with P<0.05.
Results showed that the basic architecture of the non-lactating mammary gland of rat resembled that of mouse and most domestic species except that the gland of rat consisted only of one lobe with six pairs of teats. Comparison of the three experimental groups revealed that the non-lactating mammary gland of sialoadenectomized rats presented a stroma with the thinnest capsule, fine interlobular connective tissue septa and most abundant adipose tissue in the interstitium; and the least developed parenchyma with the significantly lowest number of alveoli, least branching of these alveoli, rare secretory tubules, and fewer and smaller interlobular ducts compared with the non-lactating mammary glands of the intact and sham-operated rats.
It is concluded that total surgical removal of submandibular salivary gland in sexually mature non-lactating female rats adversely affected the amount and composition of stromal and parenchymal elements in the non-lactating mammary gland of rats.