Histochemical study on the gland of pelvis renalis in the horse.

The research article focuses on a histochemical investigation of the glands in the pelvis renalis (part of the kidney) of adult and fetal horses, specifically the intraepithelial (IE) and extraepithelial (EE) glands that are composed of mucous cells. The study also compares the glands’ reactions to various staining techniques, noting the differences which may suggest the chemical structures of sialic acid.

Understanding the Kidney Glands in Horses

• The study primarily focused on the glands located in the pelvis renalis – a part of the kidney – in adult and fetal horses.
• The researchers made use of histochemical techniques, which involves the use of chemicals to identify and visualize specific tissue components under a microscope.
• The identified glands were divided into two categories based on their locations and histochemical properties: the intraepithelial gland (IE) located within the transitional epithelium, and the extraepithelial gland (EE) located within the lamina propria.

Histochemical Characteristics of the IE and EE glands

• Both types of glands were identified as being composed of mucous cells, a type of cell that secretes mucus.
• In the IE gland, the cells were stained reddish with galactose oxidase-Schiff (GOS) and mild oxidation-Schiff (MOS) stains. They were also stained bluish purple with periodic acid-cold thionine Schiff-NaOH-PAS (PCP) stains.
• In contrast to the IE gland, the EE gland was stained weakly or not at all with GOS and MOS, but displayed a reddish purple color with PCP staining. Moreover, the EE gland was not discovered in the fetal horses, possibly suggesting it develops later in life.

Implications of Findings

• Through these staining techniques, the researchers were able to observe differences in the histochemical characteristics of these glands. These differences could reflect the underlying chemical structure of the sialic acid present in these cells. Sialic acid is a type of sugar often found at the outermost end of sugar chains attached to the surfaces of cells and influences many cellular interactions.
• These mucous cells, as indicated by the researchers, may interact with urine contents such as hippuric acid, a compound produced in the liver and excreted out of the body through urine. The study suggests that the glands might be adapted to work with such compounds. Further in-depth research will have to be conducted to confirm and further understand this hypothesis.