Morphology of intramural lymph vessels of the human heart

The structure of intraorgan system of the lymphatic collectors of the heart, their size, structure and distribution in different parts of the wall of lymphangions are described. Generation and interposition of muscle fibers in the structure of the common vessel are shown. Visual description of the interaction of different structures of the lymphatic system for lymph passage, from subendocardial lymph capillaries to the main outflow vessels is described.

Histomorphology of digestive tract in two closely related mountain newts (Salamandridae: Neurergus kaiseri and Neurergus microspilotus)

Introduction: The digestive system of vertebrates presents various structural and functional adaptations to their diverse feeding habits. Material and methods: Anatomical, histological and histochemical examinations were made from digestive tract in two closely related mountain newts (Salamandridae: Neurergus mierospilotus and Neurergus kaiseri). Sections were stained with Hematoxylin and Eosin, Periodic Acid SchifPs and Alcian Blue. Results: In both species the pharynx and esophagus are covered by psudostratified ciliated columnar epithelium with goblet cell which is positive with PAS and AB. The stomach in N. kaiseri and N. mierospilotus is a straight, expanded conical tube, laying slightly to the left side of the body cavity, and terminating at the pylorus. The stomach is divided into three distinct parts, the cardia, fundus and pylorus. Although in both species the epithelium of the stomach surface and of the lining of the crypts consists of a single layer of high columnar cell, but the apical portion of the cells in N.kaiseri consists of homogeneous acidophilic granules while in N.mierospilotus is foamy. The duodenum is short and is sharply reflexed along the medial aspect of the stomach. Duodenum in N. kaiseri and N. mierospilotus shows villi which consists of the epithelial covering and a core of connective tissue containing blood and lymph capillaries. The large intestine in both N. kaiseri and N. mierospilotus is located along the median line. The intestine is a coiled tube of a regular diameter, larger than, that of the duodenum. Histologically, these are no villi in large intestine and goblet cells rise to numerous. The epithelium is simple columnar, and the lamina propria and submocosa are strongly reduced. Conclusion: The findings of this study demonstrate that the morphological description of the digestive tract of N. kaiseri and N. mierospilotus are very similar and can be extended to the other newts.

Flow velocity in the superficial lymphatic network of the mouse tail

The present study had two goals: 1) to establish an animal model in which a large network of the initial lymphatics of the skin can be investigated in vivo and 2) to measure effective flow velocity (defined as axial component of the flow velocity) in the lymph capillary network of the skin for the first time. A fluorescence microlymphography technique was used to stain the lymph capillaries in the superficial layer of the skin of the nude mouse tail in 10 female animals (mean age 45.8 +/- 2.4 days; mean wt 21.2 +/- 0.8 g). With the use of densitometric image analysis, effective flow velocity along the tail was measured. The network consisted of a honeycomb-like layer of hexagonally shaped meshes that could be stained in all animals. Effective lymph flow velocities were in the range of 1.4-20.4 microns/s with a mean value of 7.7 +/- 5.9 microns/s; median value was 6.2 microns/s (4.5-10.5; 25 and 75% percentiles). This new animal model allows studies of a large network of lymph capillaries in the skin and should provide new insight into the physiology and pathophysiology of the initial lymphatics.

Intestinal microcirculation and transmucosal fluid transport

Blood and lymph capillaries play an important role in removing absorbed fluid from the interstitium of the intestinal mucosa. Data from the literature indicate that hydrostatic and oncotic pressures within the mucosal interstitium primarily determine the partition of absorbed fluid between blood and lymph. Alterations in the density of perfused capillaries and/or capillary permeability during absorption also influence the effectiveness of blood capillaries in removing absorbed fluid. An hypothesis regarding the roles of the interstitium, lymphatics, and capillaries during fluid transport is presented that is based mostly on whole organ studies. The effects of interstitial fluid compartmentation on interpretations of whole organ data are also discussed.