Topographical-anatomic features of the pineal gland in laboratory rats of the Wistar line

Abstract

The pineal gland is an organ of the central endocrine system that coordinates the activity of peripheral endocrine glands, immune and nervous systems, regulates biological rhythms, ensures adaptation processes and triggers the stress response. The pineal gland is inherent in almost all vertebrates, but there are different variations in the shape and location of the pineal gland in the brain of animals even within the same species. Most often, laboratory rats of the Wistar line are use for laboratory research, and for the correct interpretation of the results obtained, species-specific anatomical features and possible individual variations in the location of the pineal gland in normal laboratory rats should be taken into account. The aim of the work was to study the features of the anatomical structure and topography of the pineal gland in white laboratory rats of the Wistar line. The pineal glands of 24 sexually mature male Wistar laboratory rats were examine. Morphological, morphometric and statistical research methods were use. During the study, individual variations in the topography, shape, and blood supply of the pineal gland in laboratory rats were identify. It has been establish that in some animals the pineal gland was located in the groove between the posterior edges of the occipital lobes of the cerebral hemispheres, was richly supply with blood by a large number of blood vessels, and had either an oval or a conical shape. In other animals, the pineal gland was located in the groove between the upper anterior corpora quadrigemina. In this case, the pineal gland was supply with blood by a small number of blood vessels, and the shape of the pineal gland with such localization in the brain was rounded. Individual variations in the linear dimensions of the epiphysis have been establish. When studying morphometric parameters, it was found that the transverse size of the pineal glands was the most stable, while the vertical size was more labile, which probably caused individual differences in the volumes of the pineal glands in the studied rats. Thus, the obtained results of the study on individual variations in the anatomical, topographic and morphometric structure of the pineal gland in intact laboratory Wistar rats can be the basis for assessing pathological changes in the organ when conducting experimental studies in medical and biological fields.