The Effect Of Administration Of Thyroxine And Testosterone Hormones On The Histological And Histochemical Structures Of The Developing Submandibular Salivary Gland Of Male Rats:

Helpies Delwar Shenouda

The present study was carried out on the submandibular gland of 208 male albino rats of different ages to studythe effect of testosterone and thyroxine hormones singlyand combined on the glandular development.They are devided into 7 groups, each group consists of- 5 animals act as a control.9 animals were inj~cted wi th hormones solvents.5 animals were injected with testosterone hormone.- 5 animals were injected with thyrOXine hormone.5 animals were injected with testosterone andthyrOXine hormones.Paraffin and cryostat frozen sections were prepared tostudy the histological and histochemical parameters of thegland in addition to the quantitative measurements toreveal the postnatal changes occur ri nq in the di fferentcomponents of the glandular parenchyma.The results revealed that the postnatal development wasdivided into 2 phases; an acinar phese end a dncLa I phase.The acinar phase began from birth to the age of 6 weekswhile the ductal phase commenced thenceafter. The acinionce formed had a constant size and nearly constantfunctions: However, the ductal segments showed a steadyincrease in size and morphological change from birth to thethird month. The granular convoluted tubules were the mainstructures affected by the age factor and the hormonalinfluences.Administration of testosterone failed to accelerate theformation of acini or precocious appearance of granularconvoluted tubules at the age period below 6 weeks. Thisobservation was attributed to the lack of the specificandrogen receptors in the early postnatal period ofglandular development. After this age the hormone didinduce increaseof diameters of granular convoluted tubuleand in the number of their coarse granules but it failed tochange the diameters of both acini and striated ducts.Administration of thyroxine to the developingaccelerated the differentiation of acinus cells andpremature appearance of granular convolutedcells ( differentiated from striated ductal cellsage of 4 weeks.rats induce tubule at theSynergistically, the combination of the 2 hormones augmented the influence of either hormone solely; anotation which could be attributed to the possibility thatthyroxine might activate the androgen receptors.Histochemically; the activity of alkaline phosphatase.adenosine triphosphatase and succinic dehydrogenase enzymeswere increased after thyroxine administration whiletestosterone had no effect on enzymatic activities.The increase in enzymatic activities were pointing to increased cellular activities active transport through cell membranes to cells. collectivelyindowed with and out the In conclusion. the present investigation revealed thatthe submandibular gland of rat was not completely developed at birth as regards storma and parenchyma. also theglandular development was noticed to be under hormonal control with special reference to the activities ofgranular convoluted tubular segment.