N. G. GHOSHAL & H. S. BAL
Department of Veterinary Anatomy, College of Veterinary Medicine, Iowa State University of Science and
Technology, Ames, Iowa 50011, USA
Histomorphology of the cheek pouch was studied in 14 hamsters by light llnd transmission electron microscopy. The cheek pouch wall was devoid of any lymphatic tissue and dense subepithelial tissue (i.e. the lamina propria) would render lymph drainage almost impossible and might constitute impermeable morphological barrier for non-recognition of transplants evoking a host immune response. Because in the literature it was reported that there is absence of any arteriovenous anastomoses on the pouch wall, and interruption of arterial supply failed to alter the growth rate of tissue grafts, we speculated that epidermal growth factors present in the saliva could playa role in maintaining the growth of tissue transplants.
Keywords: Hamster; Cheek pouch; Histomorphology; Keratinized stratified squamous epithelium; Lamina propria
Fig. 1. Section of a hamster cheek pouch. (H&E stain; x 60). A, Keratinized stratified squamous epithelium; B, subepithelial connective tissue (lamina propria); C, tunica muscularis (skeletal muscle); D. adventitial connective tissue.
Fig. 2. Section of keratinized epithelium of a hamster cheek pouch showing keratin filaments in various profiles and microspaces between them (x 47 300). D. Desmosomes showing intercellular attachment sites; G, granules.
Fig. 3. Section of stratum corneum (e), and stratum granulosum of a bamster cheek pouch. Cleavage lines or spaces (5) appear in the stratum corneum, and granular structures (0) appear in the stratum granulosum (x 275(0).
Fig. 4. Section of stratum spinosum of a hamster cheek pouch. Cells depicting wavy plasma membranes with desmosomal junctions (D). Dark intracellular granules (0), microfilaments, membranous whorl-like structures related to dense granules, perinuclear mitochondria (m) and indented nuclear envelope are evident (x 16 940).