Histomorphology of Salivary Glands after Ligature and Reconstruction of Common Carotid Artery in Rabbits

Introduction. In occlusive diseases of carotid arteries may be involved salivary glands which play important role in oral and general homeostasis.Aim of the study. The purpose of this study was histomorphological evaluation of rabbit’s salivary glands after regional reduction af arterial circulation and reconstruction of ligated common carotid arteries comparing with normal histological sight.Materials and methods. The experiments were authorized by the Animal Ethics Committee of the Latvian Food and Veterinary Service. 20 male Californian rabbits weighing approximately 3 kg were used. Under intravenous general anesthesia and local anesthesia the ligature of a. carotis communis dextra was done. After 28 days 10 rabbits were sacrificed and samples were taken from all major salivary glands and histological measured acinar dimensions and acinar epithelial cell.For rest 10 rabbits under the general anesthesia were performed revascularization of a. carotis communis dextra. After 28 days the rabbits were sacrificed with intrapulmonal injection of T61. The acini dimensions and acinar epithelial cell diameter in microns in all glands were measured except buccal glands were measured. Results. In ischemic conditions all glands react with decrease of acinar epithelial cell diameter and also diametr of functional unit of salivary gland.After revascularisation reestablishment of acini and secretory epithelial cells was observed. Conclusions. Rabbit’s salivary glands have potential to recovery in diminished after ligation of ipsilateral common carotid artery size of acini and secretory epithelium after 4 week ischemia if the blood supply is reestabilished.publishersversionPeer reviewe

Smectic Liquid Crystal Observed in Thermotropic System of Rigid-Rod Poly(γ-octadecyl L-glutamate)

We investigated the thermotropic phase behavior of rigid-rod poly(γ-octadecyl L-glutamate) (PG18) with an average molecular weight Mw=36,000. Two polymers with narrow molecular weight distributions (Mw/Mn), PG18-A with Mw/Mn=1.12 and PG18-B with Mw/Mn=1.05, were prepared by gel permeation chromatography (GPC) fractionation. Both were found to form a smectic A phase by means of microscopic observations of the focal conic texture and by the small-angle X-ray method. The smectic A phase of PG18-A was transformed into a cholesteric phase at approximately 140–170\ub0C while that of PG18-B stably existed in the entire thermotropic temperature range from 60\ub0C to 220\ub0C (decomposition temperature). This dependence of smectic stability on the molecular weight polydispersity qualitatively corresponds to the theoretical prediction based on the excluded volume effect