Baoping Shao

The cranial cervical ganglion and its branches in the yak (Bos grunniens).

The heads and necks of 10 yaks were dissected to study the shape, location, arrangement, and branches of the cranial cervical ganglion. The ganglion was a greyish fusiform structure, mean length 19.72 mm, width 7.65 mm and depth 4.55 mm, located on the rostrolateral surface of the m. longus capitis. Approximately 25% of the ganglion was covered by the tympanic bulla, the rest by the m. stylohyoideus. The branches of the cranial cervical ganglion included the internal and external carotid nerves, sympathetic trunk and the branches connecting with the glossopharyngeal, vagus and hypoglossal nerves. In one animal the right cranial cervical ganglia was a greyish pyramidal structure 10 mm long, 8 mm wide and 5 mm thick but the left ganglion was similar to those found in the other specimens examined.

Histomorphometric Characterization of Forestomach of Yak (Bos grunniens) in the Qinghai-Tibetan Plateau

Six forestomachs of yaks (Bos grunniens) were studied with gross dissection and histological methods. It was found that the forestomach of yak consisted of the following three parts, rumen, reticulum and omasum, which were composed of the mucosa, submucosa, muscularis and serosa. In addition, the mucosal epithelium was covered with stratified squamous epithelium, with part of keratinized the shallow cells. Rumen, the mucosa of which formed ligulate papillae varying in size and shape, was no muscularis mucosa. Reticulum, consisted of a surface epithelium that invaginated to various extent into the lamina propria, formed various folds in shape, namely, grid-like small rooms. Furthermore, there are many secondary folds densely covered with keratinized papillae. The most striking feature of the omasum was to be formed the laminae omasi varying in length, with short and rough papillae distributing on both sides. Taken together, there was no glands within the mucosa and lamina propria of forestomach of yak, where diffuse lymphoid tissues can be observed clearly. It is, therefore, believed that the yak forestomach may have evolved those specific structural characteristics in response to the unique living environment and dietary habits impose on the Qinghai-Tibetan Plateau.

Histomorphometric Adaptation of Yak (Bos grunniens) Abomasum to the Qinghai-Tibetan Plateau Environment

Seis abomaso yak (Bosgrunniens) fueron estudiados con diseccion y metodos histologicos. Se encontro que la mucosa del abomaso yak estaba cubierta de epitelio columnar simple. Se observaron pliegues en espiral (10) en la zona glandular fundica. La membrana desarrollada de la lamina propia contenia glandulas de alta densidad. De acuerdo con las caracteristicas morfologicas de las glandulas, el abomaso se dividio en las glandulas cardiacas, gastricas y pilorica. Las glandulas cardiacas se curvan en glandulas tubulares con la parte inferior intumescente y una pequena cavidad glandular. Las glandulas fundicas eran glandulas tubulares simples o glandulas tubulares ramificadas, donde se pueden observar con claridad las celulas principales, parietales y mucosas del cuello. Las glandulas piloricas fueron glandulas tubulares curvadas, cuanto mas cercanas a la lamina propia, mas evidente fue su forma ondulada. La tincion glucoconjugada revelo que el epitelio de la mucosa de las glandulas gastricas cardiacas, piloricas y el epitelio de las fosas gastricas secretaron principalmente un glucoconjugado neutro, pero otras porciones cardicas y de las glandulas gastricas secretaron un glucoconjugado mixto y acido, respectivamente. A la tincion de fibras reticulares, se encontro que las celulas mucosas del cuello poseian caracteristicas argirofilas. Se observo un gran numero de granulos en el citoplasma supranuclear en contraste con las celulas principales. Ademas, no fueron aislados los nodulos linfoides y presentaba tejido linfoide difuso en las glandulas de abomaso, especialmente en el cuerpo del abomaso. La tincion Gordon Sweet indico que las celulas argirofilicas se localizaron en el epitelio y lamina propia glandular, lo que tambien se observo en el tejido conectivo. Estas celulas endocrinas se dispersan individualmente en las celulas epiteliales, de vez en cuando en grupos celulares de 3-5. De esta forma, los yak pastorean durante todo el ano, en diversos pastizales naturales, y han evolucionado sus caracteristicas morfologicas que les permiten consumir una amplia variedad de especies de plantas, con lo que se adaptan mejor a las condiciones inhospitas.

Immunoexpression of aquaporins 1, 2, 3 and 4 in kidney of yak (Bos grunniens) on the Qinghai-Tibetan Plateau

ABSTRACT Aquaporins (AQP) 1, 2, 3 and 4 belong to the aquaporin water channel family and play an important role in urine concentration by reabsorption of water from renal tubule fluid. Renal AQPs have not been reported in the yak (Bos grunniens), which resides in the Qinghai Tibetan Plateau. We investigated AQPs 1−4 expressions in the kidneys of Yak using immunohistochemical staining. AQP1 was expressed mainly in the basolateral and apical membranes of the proximal tubules and descending thin limb of the loop of Henle. AQP2 was detected in the apical plasma membranes of collecting ducts and distal convoluted tubules. AQP3 was located in the proximal tubule, distal tubule and collecting ducts. AQP4 was located in the collecting ducts, distal straight tubule, glomerular capillaries and peritubular capillaries. The expression pattern of AQPs 1−4 in kidney of yak was different from other species, which possibly is related to kidney function in a high altitude environment.

Anatomical and histochemical features of the bulbourethral glands in bactrian camel (Camelus bactrianus)

Anatomical and histochemical features of bulbourethral glands in the Bactrian camel were investigated by gross-anatomical, histological and histochemical methods, and also by transmission microscope. The bulbourethral glands are compound tubuloalveolar glands, surrounded by a capsule of dense connective tissue. The lobules of the glands are formed by secretory units and excretory ducts, which are both lined by a single epithelium of mucous cell with a basal nucleus. Three types of secretory unit, designated A, B and C, were observed in the glands. Type A is lined with high columnar cells and the cytoplasm contains lots of secretory granules, which are PAS-positive, Alcion Blue-positive but Toluidine blue-negitive. Type B is lined with pyramidal or cuboidal cells and the cytoplasm shows PAS-positive, Alcion Blue-positive and Toluidine Blue-positive. The ultrastructures of epithelial cell shows that amount of granules with different electron density occupy the most space in the cytoplasm. Secretory granules can contain round inclusion. The shape of the epithelium varies according to the different stage of the secretory cycle.

Renal expression and functions of AQP1 and AQP2 in bactrian camel (Camelus bactrianus)

Aquaporin (AQP) 1 and AQP2 belongs to the aquaporin water channel family, which play a main role in reabsorption of water from the renal tubular fluid to concentrate urine. With paraffin section method combined with transmission electron microscopy, the microstructure and ultrastructure of bactrian camel (Camelus bactrianus) kidney was observed. We studied nephron segment-specific expression of AQP1 and AQP2 using immunohistochemical staining on paraffin sections of camel kidneys. We found that the microstructure and ultrastructure of kidneys in camel, was similar to those of other animals. However, the structure of the various parts of nephron were developed, especially, proximal tubule brush border. Moreover, strong expression of AQP1 was observed in the apical and basolateral membrane of epithelial cells in proximal tubule and Henles loop descending limb. AQP2 was strongly expressed in apical membrane and cytoplasm of principal cells in the collecting duct and epithelial cells in the distal convoluted tubule. In conclusion, strong expression of AQP1 and AQP2 in the camel kidney showed some differences from other species in renal trans-epithelial water transport, these results enhanced our better understanding of special water metabolism mechanisms, to some extent, it may be one of the secrets of camel to survive in the extremely arid and harsh environment.