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Open Access
ANATOMICAL STUDIES ON HAIR OF INDIAN SPOTTED DEER (Axis axis), BLACKBUCK (Antelope cervicapra) AND ASIAN ELEPHANT (Elephas maximus)
(SRI VENKATESWARA VETERINARY UNIVERSITY TIRUPATI - 517 502. (A.P.) INDIA, 2012-12) VINAYA SHEELA, S; PURUSHOTHAM, G(MAJOR); PRAMOD KUMAR, D; LAKSHMAN, M
ABSTRACT : The present study was undertaken on hair samples of Spotted deer, Black buck and Asian Elephant since they are considered as endangered species. Further the former two species are listed under Indian Wild life Act 1972. Six animals were selected from each species from Nehru Zoological park. Hair samples from six different regions viz., neck, back, lateral abdomen, forelimb, hind limb and tail were collected from each animal and processed for microscopic physical observations, cast technique for scale pattern and for SEM (scanning electron microscope) studies. Microscopic structure of hair of spotted deer and black buck comprised of cuticle, cortex and medulla from without inwards. Hairs of tail and back region of elephant had a cortex, cuticle and whereas all other regions lacked a typical medulla. Color variation was observed between the hairs of different species within an individual and also within an individual hair. Color of hairs collected from six different regions varied from colorless to blackish brown in spotted deer, colorless to dark brown in black buck and from light yellowish brown to dark brown in elephant. Tips of hair shafts in spotted deer were frayed in neck, abdominal and tail regions and were blunt in rest of the regions. In black buck hair tips were frayed in neck region, rounded in hind limb region whereas it was pointed in other regions. In elephant, hair tip was rounded in all regions except in the back and forelimb where hair tips were broken. The cuticle was a translucent colorless outer structure of hair shaft but light brown in hair of neck and back regions in spotted deer and in neck of black buck hair. In elephant hair it was colorless in all regions with light blackish brown margin. Smooth cuticular pattern throughout the length of hair was noticed in most of the regions of three species. Serrated cuticle was seen in the tip of forelimb hair in spotted deer, throughout the length of hair in tail region and mid shaft of forelimb in blackbuck. In back region of elephant it was wavy throughout the length. Cross sectional shape of hair shaft of spotted deer varied from oval to round. It was bean shaped in black buck but was rod shaped in the tip, oval, triangular or round near to base of the shaft in hair of tail region and round in the base of neck. Cross sections of hair in elephant were round. Cortex pattern was smooth throughout the length of hair in spotted deer whereas in black buck it was coarse in the tip and mid shaft of abdomen hair. It was coarse in the hair of all regions in elephant except for tip hairs of neck region. Cortical fusi were present in the proximal part of hair in tail region of spotted deer and back region of blackbuck. No ovoid bodies were observed in hair of spotted deer but were seen towards the base of the shaft of back, hind limb region hair in black buck and in the tip of the hair in abdomen and hind limb hair of elephant. Medulla was lattice type in spotted deer hair whereas it was non lattice type in black buck hair. Vacuolated medulla was evident towards base of the shaft in the hair of tail region in black buck. Medulla was absent in the tip and was tapered towards tip of the shaft in spotted deer and black buck hair. Medulla was not evident in the hair of elephant from all regions except in back and tail hair where multiple medulla was noticed. It was fragmentary or trace like towards tip of the shaft in spotted deer and black buck and its margins were scalloped in spotted deer. Scalloped, irregular and straight medullary margins were present in black buck hair. Wine glass shaped tapered medulla, fragmentary or widened towards base of the shaft were seen in spotted deer and black buck hair. Variation in pigment distribution was evident within individual hair of spotted deer and black buck. In former it was uniform, medial and random while in black buck it was uniform and banded and in elephant it was uniform. A significant difference of mean cortical thickness, medullary diameter, and medullary index of hair between spotted deer and blackbuck was noticed. Shaft diameter of three species differed significantly not only between species and different body regions but also within an individual hair. SEM studies revealed difference in scale pattern in the tip, mid shaft and base of an individual hair in spotted deer and black buck. Imbricate scale pattern with overlapped scales were present in the mid shaft and coronal type in the tip of the shaft. They were faint and distantly placed towards base of the shaft, but were compact in the elephant hair. Margins of the scales were smooth to slightly rippled in mid shaft region and towards the base of the shaft in spotted deer whereas it was smooth in black buck and rippled in elephant hair. Trough on surface of hair was an important feature of blackbuck hair that made it easy to differentiate from that of spotted deer hair. Number of scales per 100 μm length of hair was more at the tip in spotted deer (21.55-22.50) and blackbuck (18.05-20.52). In general scale width was more in the base of the shaft and diameter of mid shaft was more than base. Imbricate scale cast pattern was seen in hairs of spotted deer and black buck towards mid shaft and base. Hair tip showed coronal pattern in spotted deer and black buck. Scale cast imprints were not amenable in shaft of elephant hair which indicates adherence of scales to the shaft surface.
Open Access
PRENATAL DEVELOPMENT OF VERTEBRAL COLUMN, RIBS AND STERNUM OF BUFFALO (Bubalus bubalis)
(SRI VENKATESWARA VETERINARY UNIVERSITY TIRUPATI - 517 502. (A.P.) INDIA, 2011-09) BHAGYA LAKSHMI, J; JAGAPATHI RAMAYYA, P(MAJOR); Chandrasekhara Rao, T.S; Sri Latha, Ch
ABSTRACT : The study was made on 46 embryos with their age ranging from 41 to 280 days (2.8 to 91.6 cm CVRL) to study the ossification centres in bones of vertebral column, ribs and sternum. The vertebrae, sternum and ribs of buffalo were developed by endochondral ossification. Three different stages were observed during their development i.e stage of mesenchyme, chondrification and ossification. In general the cervical vertebrae were developed from three principal centres of ossification i.e one for the centrum and two for the neural arches. Atlas showed total three ossification centres viz., 2 for neural arches and one separate ossification centre for ventral arch. The ossification centres of neural arches of the atlas were largest among the cervical vertebrae. Axis showed total four ossification centres viz., one each for neural arches, one for body and one separate ossification centre for odontoid process. The locus of ossification for neural arches and body of axis were appeared first at 64 days of gestation in buffalo. Ossification centre for odontoid process was noted first time in anterior cartilaginous mass of axis at 114 days of gestation. Thoracic vertebrae developed from four ossification centres viz., two for neural arches, one for the centrum and separate ossification centre was noted for dorsal spinous process.. The lumbar vertebrae were developed from three ossification centres viz., one each for the neural arches and one separate ossification centre for body of the vertebrae. The transverse processes of lumbar vertebrae developed from neural arches as lateral outgrowth. Sacral vertebrae showed 3 ossification centres for each vertebra i.e one each for neural arches and one for centrum. The first four coccygeal vertebrae developed each from three centres of ossification i.e one for the centrum and two for the neural arches, whereas the more caudal of the group developed from only one centre of ossification. The cartilaginous precursor of sternum was identified first histologically at 54 days as the bilateral cores of cartilage cells. The locus of ossification in the sternal segments was central, unpaired and continued to the area of 7th sternal segment. The 2nd sternebra was the last segment to show ossification and this segment has appeared for first the time at 143 days of gestation. Ossification was first noted in the shaft of the ribs from 2nd to 6th at 59 days and at 64 days all ribs i.e from 1 to 13 showed ossification.The secondary ossification centres have appeared in heads of first 6 pairs of ribs at 155 days and tubercular facets were identified at 181 days radiographically in ribs. In one specimen, the incidence of supernumerary ribs (14th pair) was also noted in the present study.
Open Access
MICROANATOMICAL STUDIES ON THE TESTIS AND PINEAL GLAND OF ADULT RAM (Ovis aries)
(SRI VENKATESWARA VETERINARY UNIVERSITY TIRUPATI - 517 502. (A.P.) INDIA, 2015-10) GOPI KRISHNA, B; RAJU, N.K.B(MAJOR); JAGAPATHI RAMAYYA, P; DHANA LAKSHMI, N
ABSTRACT : The present work on microanatomical studies on the testis and pineal gland of adult ram (Ovis aries) was conducted on adult healthy rams. The testis was enclosed by a capsule the tunica albuginea and a visceral tunica vaginalis. The tunica albuginea was composed of very dense collagen and reticular fibres and several blood capillaries noticed at deeper portion of the tunica albuginea. The mean thickness of the tunica albuginea was 558.37 ± 26.63 μm. Centrally located mediastinum testis with collagen fibres predominantly. The convoluted seminiferous tubules were lined by spermatogenic epithelium which was stratified showed spermatogonia, spermatocytes, spermatids, spermatozoa and Sertoli cells. The seminiferous tubules were separated from each other by interstitial tissue. The mean diameter of the seminiferous tubules was 128.45 ± 3.15 μm. The spermatogenic cells located in groups between the Sertoli cells, in three to seven layers. Three types of spermatogonia were observed viz., A-type, Intermediate type and B-type spermatogonia. The A-type spermatogonia were largest and had a round nucleus with fine chromatin granules. The intermediate type spermatogonia had a spherical nucleus with centrally distributed chromatin. The B-type spermatogonia consisted of small and spherical nuclei with thick chromatin concentration. The primary spermatocytes had spherical shaped darker nuclei with lightly stained cytoplasm. The secondary spermatocytes were rounded in shape with centrally placed spherical nucleus and scanty cytoplasm. The spermatids were smallest cells of the spermatogenic epithelium. They were round or elongated possessed spherical or elongated nuclei with thin peripheral cytoplasmic rim. The Sertoli cells were located in between the spermatogenic cells and they were elongated tall columnar type rested on the basement membrane with indistinct cell boundaries and had large deeply indented ellposidal nucleus with homogenous nucleoplasm. The Leydig cells were located in the meshes of interstitial connective tissue in single or groups with a large centrally placed spherical nucleus and granular cytoplasm. The capsule of testis, basement membrane of the seminiferous tubules and maturing spermatids showed strong positive reaction for neutral and acid mucopolysaccaharides and very weak reaction for lipids. Strong reaction for lipids was noticed in spermatogonia and the primary spermatocytes and moderate reaction for lipids in spermatids and Leydig cells. The spermatogonia, primary and secondary spermatocytes and Sertoli cells showed weak reaction for PAS and wall of blood vessels showed moderately positive reaction for PAS. The Leydig cells showed strong reaction for glycogen. The acid phosphatase activity was strong in the basement membrane and spermatogenic cells and moderate to weak in Leydig cells. Alkaline phosphatase activity was mild in seminiferous tubules and almost negative in the interstitial tissue. The pineal gland in adult ram was highly vascularised and innervated by nerve fibres and had a very thin capsule. Capsule was made up of collagen and reticular fibres with indistinct lobulation. The parenchyma consisted of two types of cells viz., pinealocytes and interstitial cells scattered throughout the interstitial tissue. The interstitial tissue was made up of reticular and collagen fibres observed in the vicinity of blood vessels. Pinealocytes were the thickly populated at the periphery and arranged in cords in the centre portion of the gland. The pinealocytes showed oval or round nucleus and possessed numerous cytoplasmic processes. Ultrastructurally, the pinealocytes were categorised into light and dark types. The light pinealocytes had round to oval nucleus with one (or) more nucleoli with chromatin material accumulate as smaller clumps attached to the nuclear membrane. Dark pinealocytes were sparse and showed pear shaped nuclei with irregular outer surfaces with evenly distributed chromatin material. The interstitial cells were neuroglial cells categorised into three types. Type-1 cells were large, oval (or) round with one (or) two processes and distributed as small groups showed smooth surface and chromatin material was aggregated in small irregular clumps towards the nuclear membrane. Type-2 cells had large, elongated (or) oval nuclei. Type-3 cells were smaller and showed numerous fine processes mainly associated with blood vessels and had large indented nuclei. PAS activity was mild in capsule of the pineal gland and interstitial cells, strong pinealocytes and intense in blood vessels. The interstitial cells showed moderate to strong reaction for acid mucopolysaccaharides in their cytoplasm. The pinealocytes and the interstitial cells showed very mild reaction for alkaline phosphatase and intense acid phosphatase activity. The varied sizes of corpora arenacea were observed in the pineal parenchyma.
Open Access
GROSS AND MICROANATOMICAL STUDIES OF THE STIFLE JOINT IN PRE AND POSTNATAL STAGES OF THE BUFFALO (Bubalus bubalis)
(SRI VENKATESWARA VETERINARY UNIVERSITY TIRUPATI - 517 502. (A.P.) INDIA, 2013-12) BHARATH KUMAR, M.L; PRAMOD KUMAR, D; ANJENAYULU, Y; RAJENDRANATH, N
Open Access
GROSS, HISTOLOGICAL AND HISTOCHEMICAL STUDIES ON THE PANCREAS OF ALBINO RAT (Rattus norvegicus)
(SRI VENKATESWARA VETERINARY UNIVERSITY , TIRUPATI – 517502. (A.P.) INDIA, 2013-07) RAYAZ AHMED; JAGAPATHI RAMAYYA, P (Major); RAJU, N. K. B.; Suresh Kumar, R V
ABSTRACT : The study was conducted on twelve albino rats (Rattus norvegicus). The pancreas was a diffuse lobulated gland and appeared pink in colour. The gland was divided into three parts viz., gastric, splenic and duodenal parts. The pancreas of the rat was covered by a thin capsule, made up of predominantly, collagen fibres. Each acinus showed a single row of pyramidal epithelial cells resting on the basement membrane. The cytoplasm of the acinar cells showed two distinct zones. The basal zone was dense and basophilic, while the apical region contained the numerous fine zymogen granules. Two types of acinar cells were noted in pancreas i.e active and resting type. In active cells the nucleus was spherical, euchromatic and located at the centre, whereas resting cells possessed heterochromatic nucleus and placed close to base of the cell. The duct system of the pancreas consisted of larger interlobular, medium sized intralobular and small intercalated ducts. The endocrine tissue appeared as lightly stained rounded or oval areas between the darkly stained acini. In albino rat three different types of islets were observed. They were small, medium and large islet types. The alpha and pancreatic polypeptide cells occupied the peripheral region in the islet. Whereas, beta cells were mostly present in its interior. Delta cells were distributed randomly throughout the islets and they were long, flattened, irregular in shape and characterized by the presence of small granules. The pancreatic polypeptide cells were found singly or in clusters at the periphery of the islets. The pancreas of rat was supplied by celiac and anterior mesenteric arteries. The blood capillaries in the islets had typically fenestrated endothelium walls and were greatly extended, tortuous or large in calibre as compared with the capillaries of the exocrine pancreas. The lymph vessels were present in the exocrine part, whereas the endocrine portion was devoid of lymph vessels. They were characterized by thin walls and showed fenestrated endothelial cells and devoid of pericytes. The nerve bundles were divided into several thick and thin branches and they formed nervous plexus in pancreas of rat. According to the localization in the organ, the pancreatic nervous plexus were divided in to four types viz., periacinous, periinsular, perivascular and periductal plexuses. The nerve cells were observed either as isolated cells, small ganglia or large sized ganglia in rat pancreas. The isolated nerve cells were generally present in the islets. The ganglionic cells occupied a peripheral position in the islets of Langerhans in rat. The secretory cells of the acini and the epithelial cells of the pancreatic ducts showed strong positive reaction for Periodic acid Schiff. But moderate activity was noted in islets of Langerhans in pancreas of rat. The secretory cells of the acini and islets showed moderate to strong reaction for alcian blue. Further, epithelial cells of the pancreatic ducts showed strong positive reaction for alcian blue. The islets of Langerhans showed strong positive reaction for Best’s carmine. The epithelial cells of the pancreatic ducts also showed strong positive reaction for glycogen in the present study. In rat secretory cells of acini showed mild reaction for Best’s carmine. The secretory acini showed mild reaction for bromophenol blue, whereas islets of Langerhans showed strong reaction.
Open Access
HISTOMORPHOLOGICAL STUDIES ON CEREBRAL AND CEREBELLAR CORTICES OF RATS EXPOSED TO METHYL MERCURY
(SRI VENKATESWARA VETERINARY UNIVERSITY TIRUPATI – 517 502. (A.P) INDIA, 2015-12) NAGENDRA REDDY, MOILLA; NAGAMALLESWARI, YAMANI (MAJOR)
ABSTRACT: The present study was conducted on 36 adult male Sprague Dawley rats aged 6 weeks, which were randomly grouped into control (group I), 2.5ppm methyl mercury exposure (group II) and 5ppm methyl mercury exposure (group III). There was a significant increase in body weight of 5ppm group compared to 2.5ppm and control groups at 35 days post exposure. Mean brain weight was higher in 5ppm group at 14 days post exposure and 2.5ppm group at 35 days post exposure. The average length of brain was higher in both the treated groups when compared to control at 14 days post exposure.Histological study of motor and visual area of cerebral cortex revealed deranged cortical cell organization with reduced number and shrunken neurons in both the treatment groups at 14 days post exposure and further increased in 35 days of exposure. In the motor area Perineuronal space, haemorrhages in capillaries and vacuolation in neuropil were evident in 5ppm group at 35 days post exposure. Deranged neurofibrillar network was also observed. Astrogliosis was observed in all the treated groups but more evident in 2.5ppm group at 35 days post exposure. The visual cortex showed increased vascularity with hypertrophy of the capillaries in both the treated groups and was markedly visible in 5ppm group at 35 days post exposure compared to 14 days post exposure. Ruptured endothelial basement membrane was thrown in to capillary lumen, astrocytes invaded in to some capillaries, vacuolated external and internal pyramidal cells were more evident in 2.5ppm compared to 5ppm in 35 days than at 14 days post exposure. This might be one of the reasons for the disruption of blood brain barrier in low doses for long period of exposure.In the cerebellar cortex, the average thickness of molecular cell layer, granular cell layer, average number and size of Purkinje cells were reduced in both the treated groups in both the treatment periods. Many of the Purkinje cells lost their dendritic arborization at 14 days post exposure and were further intensified in 5ppm than in 2.5ppm group at 35 days post exposure. Purkinje cell shape was altered in both exposure periods in 5ppm group and loss of nucleoplasm and karyolysis in 2.5ppm at 35 days post exposure. In the granular layer, granule cells were disoriented and few altered in their shape in both the treatment groups at 35 days post exposure. Vacuolation was predominant in 5ppm group at 14 and 35 days post exposures and also disorganized afferent and efferent fibers and loss of basket around the Purkinje cells were observed. Autometallographic analysis revealed the accumulations of mercury particles in neuropil, neuronal cell bodies and capillaries of motor and visual areas of cerebral cortex and also observed at the capillary walls. Molecular, Purkinje and granular layers showed the presence of mercury particles in the neuropil, Purkinje cells and granular cells. Sub cortical white matter was also presented with mercury localization in both the treatments with various intensities.
Open Access
HISTOMORPHOLOGICAL CHANGES IN THE TESTIS OF RATS EXPOSED TO METHYL MERCURY IN RELATION TO PITUITARY-TESTICULAR AXIS
(SRI VENKATESWARA VETERINARY UNIVERSITY TIRUPATI – 517 502. (A.P) INDIA, 2014-10) KARUNA SRI, VADDI; NAGAMALLESWARI, Y(MAJOR); KISHORE, P V S
ABSTRACT: This study was conducted on 36 adult male Sprague Dawley rats of 6 weeks age. These subjects were randomly assigned into three groups, viz. control (group I), 2.5ppm methyl mercury exposure (group II) and 5.0ppm methyl mercury exposure (group III). Methyl mercury was fed in the form of methyl mercuric chloride in drinking water daily. There was a significant increase in body weight in the 5.0ppm group than in the 2.5ppm and control groups at 35 days of exposure. Elongated bean shaped testes were present. The average total testes weight also increased significantly in both the treated groups than in the control group at 35 days post exposure. The average length and width of both right and left testes increased in 2.5 and 5.0ppm groups when compared to the control at 14 days of exposure. In the high dose (5ppm) group there was a significant increase in the average width of the right and left testis compared to the control at 35 days post exposure. The length and width of the left testis in both exposure groups was significantly increased.There was a significant increase in the mean sperm count in rats of 2.5ppm group than in other groups at 14 and 35 days post exposure. The average number of head and tail abnormalities also increased in both treated groups during the same period. The average serum total testosterone level increased significantly in the 5.0ppm group than in 2.5ppm and in the control groups at 14 days post exposure. However, there was no significant increase in the serum total testosterone level among all the three groups at 35 days post exposure.The thickness of tunica albuginea (capsule) of testis was reduced in both the treated groups (2.5 and 5.0ppm) at 14 and 35 days post exposure. A potential space was seen between the basal and adluminal compartments at 14 days post exposure in both the treatment groups. No potential space was observed in the control group. Hypertrophy and vacuolation of sertoli cells were present in both the treated groups at 14 and 35 days post exposure. Normal cohort of 5-6 types of cell arrangement was lost in both the treated groups at 14 and 35 days post exposure. Mitotic divisions were seen in the group given 5ppm at 14 days post exposure and in both the treated groups at 35 days post exposure. Thinning and degeneration of the peritubular membrane was found in both treatments at both the exposure periods. Altogether, the above changes lead to disruption of blood-testis barrier. Hypertrophy and vacuolation of leydig cells were observed in the interstitium of testis in both the treatment groups compared to the control at 35 days post exposure.The average weight, length and width of pituitary glands increased in both treated groups compared to the control and it was statistically significant at 14 days post exposure. Hypertrophy of B1 (LH cells) and B2 (FSH cells) was observed in the treated groups of both exposures compared to the control. B2 cells were present in clusters at the postero-lateral aspect of pars distalis. Some cells showed a centrally placed nucleus while others had a peripheral nucleus. Vacuoles were present on the apical surface of nucleus which might represent the Golgi complex in the 2.5ppm group. This might be an indication of the secretory state of cells. No vacuoles were found in the control group. Hypertrophy of sub capsular capillaries was observed at the periphery of pars distalis.
Open Access
HISTOLOGICAL AND HISTOCHEMICAL STUDIES ON THE COAGULATING AND PREPUTIAL GLANDS OF ALBINO RAT (Rattus norvegicus)
(SRI VENKATESWARA VETERINARY UNIVERSITY TIRUPATI – 517 502. (A.P) INDIA, 2013-11) BINDU, MOTUPALLI; KISHORE, P V S (Major); RAJU, N. K. B; SREENU, MAKKENA; NAGA MALLESWARI, Y
ABSTRACT : The study was undertaken on the light microscopic and ultra structure of the coagulating and preputial glands. These were the two additional paired male accessory sex glands in the rat. For this study 10 albino rats were used. The coagulating glands of either side were located along the inner curvature of the seminal vesicles. Each gland formed a single narrow duct that opened into the urethra alongside the duct of the seminal vesicle. The gland was compound tubular. The secretory units and the ducts were lined by simple cuboidal or low columnar epithelium which projected into the lumen and formed folds inside the compartments. The mode of secretion was both merocrine and apocrine. Ultrastructural study revealed secretory cells of different electron density. The cytoplasm also contained the secretory granules and the vacuoles of different sizes towards the luminal side which showed the surface microvilli. A weak PAS positive reaction was observed in the gland. A positive reaction for proteins was observed in the cytoplasm of the secretory cells and in the luminal fluid. No reaction for lipids was observed. A mild acid phosphatase activity was observed in the secretory cells located peripherally. A very weak alkaline phosphatase activity was observed towards the luminal side in the epithelial cells of the secretory units and the ducts. The preputial glands were small and elongated flask shaped structures on either side of the penis in the male. They were compound alveolar glands of the holocrine type. Each acinus increased in size with the continued storage of fatty substances. Small , rounded acini with a layer of flattened peripheral cells, enlarged acini composed of hypertrophied, vacuolated cells and acini with cellular degeneration and a distinct lumen, several of which fused to form large masses of disintegrating cells were also observed. The above states of activity represented the cycle of sebum formation. The gland was not associated with the hair follicle. The main excretory duct emptied into the area between the inner surface of the prepuce and glans penis. Ultrastructural study revealed cells of different sizes in different phases of secretory activity. The cytoplasm contained several small secretory granules and small to large lipid droplets. Well developed endoplasmic reticulum along with numerous golgi complexes were observed. The large cells had spherical nuclei with evenly dispersed euchromatin along with peripheral heterochromatin. A PAS positive reaction was observed in most regions of the gland. It showed only a slight decrease in reactivity but remained almost similar upon treatment with saliva. Fine protein granules were observed in the smaller acinar cells and large sized granules were observed in the central acinar cells approaching degeneration. Abundant lipid droplets were observed throughout the acinar cells. A mild acid phosphatase activity was observed in some of the acinar cells. A weak alkaline phosphatase activity was observed in the secretory acini that were in active phase of secretion.
Open Access
HISTOLOGICAL AND HISTOCHEMICAL STUDIES ON THE STOMACH OF ALBINO RAT (Rattus norvegicus)
(SRI VENKATESWARA VETERINARY UNIVERSITY TIRUPATI – 517 502. (A.P) INDIA, 2011-09) SATYA SAI CHANDANA, GADULA; KISHORE, P V S (Major); RAJU, N. K. B; SREENU, MAKKENA; SRINIVASA RAO, G
ABSTRACT : The present work was undertaken to study the normal light microscopic structure, ultrastructure and histochemistry of the stomach of the Albino rat to form a baseline for interpretation of the changes brought about by the drugs upon testing. The tissue pieces were obtained from the oesophageo-gastric junction, non glandular region, limiting ridge, glandular region and the pyloric-duodenal junction of the stomach. The ‘C’ shaped stomach of rat located in the left cranial part of the abdominal cavity was divided into the larger nonglandular and smaller glandular regions separated by a limiting ridge. The nonglandular region served as a reservoir, the limiting ridge prevented reflux of ingesta into the oesophagus and the glandular region aided in digestion. Its wall was composed of four tunics: mucosa, submucosa, muscularis and serosa. The mucosa of glandular stomach comprised the cardiac, fundic and pyloric regions based on the nature of glands observed. In the cardiac region the glands were branched tubular coiled and composed almost entirely of mucous secreting cells along with a few chief cells. In the fundic region the proper gastric (fundic) glands were simple tubular and longer than the cardiac glands. Structurally and functionally four distinct cell types comprised the secretory epithelium of the proper gastric glands: mucous cells, chief cells, parietal cells and endocrine cells. In the pyloric region the glands were branched coiled tubular glands several of which opened into each of the deep pyloric pits. The predominant cell was mucous-secreting. At the pyloric duodenal junction muscle layers were thickened to form the pyloric sphincter. A mild Periodic Acid Schiff (PAS) positive reaction was observed in all the tunics of nonglandular region except the epithelium. In the glandular region a strong PAS positive reaction was observed in the mucous cells. The remaining tunics showed a mild to moderate reaction. Surface mucous cells and mucous neck cells showed a positive reaction for acid mucopolysaccharides. The reaction for proteins was very weak in all the regions of the stomach. In the nonglandular region a faint reaction for lipids was observed in the superficial layers of epithelium. In the glandular region, the reaction was observed in the tunica submucosa. Fine isolated granules of lipids were observed in all the other tunics except epithelium. A strong acid phosphatase activity was observed only in the epithelial cells of the non glandular region. The alkaline phosphatase activity was observed in the epithelium of nonglandular and limiting ridge regions. In the glandular mucosa, the activity in the parietal cells was strong. In the nonglandular region, a strong succinic dehydrogenase activity was observed in the basal layers of epithelium. In the glandular mucosa, a strong reaction was observed in the parietal and mucous neck cells. Chief cells showed moderate activity.

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