Sexual dimorphism in histological structure of normal rat stomach / Dimorfismo sexual en la estructura histológica del estómago normal de la rata

Fifty male and fifty female Spargue-Dawley rats were randomly chosen and used to study the sexual dimorphisms of stomachic histological structures. The rat stomach consisted of the nonglandular part and the glandular part. The gender differences of the nonglandular part existed in the thicknesses of the stratified squamous epithelium and the longitudinal muscle. These findings revealed that the male rat stomach may storage more foods than the female. The gastric glands occupied all the lamina propria in the glandular part. The thicknesses of the gastric glands of the female and male rat were 525.0 ± 95.9 µm and 472.0 ± 158.7 µm respectively, and the difference was very significant (p<0.01). The gastric glands could be divided to two layers in the HE stain, i.e. the luminal and the basal layers. The thicknesses of the luminal layer of the female and male rat were 289.7 ± 95.9 µm and 300.0 ± 120.7 µm respectively, and the difference was insignificant (p>0.05). On the contrary, the thicknesses of the basal layer and the three muscle layers in the female glandular part were all thicker than those in male, and the differences were very significant (P<0.01). These findings indicated that the female rat stomachs may have a more powerful digestive ability than the male ones. The nucleus-glandular index of the gastric gland of the normal female and male rat were 0.19 ± 0.05 and 0.18 ± 0.04 respectively, and the difference was insignificant (p>0.05).

Se seleccionaron al azar 100 ratas Sprague-Dawley, 50 de sexo masculino y 50 de sexo femenino, para estudiar los dimorfismos sexuales de las estructuras histológicas del estómago. El estómago de la rata consiste de una parte no glandular y de una parte glandular. Existen diferencias de género en la parte no glandular en relación al espesor del epitelio escamoso estratificado y del músculo longitudinal. Estos hallazgos revelaron que el estómago de las ratas masculinas puede almacenar más alimentos que las hembras. Las glándulas gástricas ocuparon toda la lámina propia de la parte glandular. Los espesores de las glándulas gástricas de la rata hembra y macho fueron 525,0±95,9 mm y 472,0±158,7 mm, respectivamente, y la diferencia fue muy significativa (p <0,01). En la tinción de Hematoxilina-Eosina (H-E) se visualiza la división de las glándulas gástricas en dos capas, es decir, en las capas luminal y basal. Los espesores de la capa luminal de la rata hembra y macho fueron 289,7±95,9 mm y 300,0±120,7 mm, respectivamente, y la diferencia fue no significativa (p> 0,05). Por el contrario, los espesores de la capa basal y las tres capas musculares en la parte glandular fueron más gruesos en las ratas hembras y las diferencias fueron muy significativas (p <0,01). Estos hallazgos indicaron que los estómagos femeninos de rata pueden tener una capacidad digestiva más potente que los masculinos. El índice núcleo-glandular de la glándula gástrica de la rata normal femenina y masculina fue 0,19±0,05 y 0,18±0,04 respectivamente, y la diferencia fue no significativa (p> 0,05).

The histochemical assessment of sulpho-, sialo-, and neutralmucosubstances in fetal gastric mucosa.

Background: Mucins are complex composition of carbohydrates and may be present as a mixture of different types. Normal distribution of mucin and its alteration in various inflammatory, benign and malignant lesions of gastrointestinal tract has aroused interest in the field of histochemistry. The main purpose of present work is to study the staining pattern and distribution of cells in different parts of fetal gastric mucosa and to correlate the nature of gastric mucins and its functional significance. Methods: A total of 25 fetus stomach specimens (total 75 samples) one sample each from different parts of the stomach like fundus, body and pylorus, from fresh specimens. The samples were washed in normal saline, fixed in 2% calcium acetate in 10% formalin. These tissues were routinely processed and paraffin blocks were prepared. 6  sections of these blocks were taken for histological and different histochemical staining. Results: Fetal fundic part of stomach shows increased neutral mucin in surface epithelium and foveolar cells. With combined AB pH 2.5 - PAS technique increased neutral mucin and small amount of acid mucins are observed. With AB pH 1, surface epithelium and deep glands show negative staining. Moderate alcinophilia is observed in deep foveolar cells and glandular cells. AB pH 2.5 shows alcinophilia in surface epithelium, foveolar cells and mucous neck cells indicating presence of sialomucin. Fetal pyloric part of stomach shows increased acid and neutral mucins. With pH 2.5 - PAS staining, purple staining is observed in surface epithelium, deep foveolar and pyloric glands. Conclusion: All types of mucosubstances - neutral, sialo and sulpho-mucins, are secreted in relatively increased amounts by the surface epithelium and the glands of the stomach of the human fetus and neonate. Sulphomucin is seen mainly in the cells of the surface epithelium.