Morphology of kisspeptin-producing nuclei in the rat hypothalamus

ВACKGROUND: The article is devoted to the stereo-morphological analysis of the nuclei of the hypothalamus, synthesizing proteins of the kisspeptin family, regulating sexual differentiation — various parts of the extended kisspeptin-producing nuclei of the hypothalamus and the features of their asymmetry in mature rats. The morphology of various parts of extended kisspeptin-producing nuclei of the hypothalamus remains poorly understood, which significantly complicates the choice of their reference zone, from which planning and implementation of morphological studies should begin, related to the evaluation of the effectiveness of therapeutic correction of various forms of hypogonadism.

AIM: Determination of the main source of regulatory peptides of the kisspeptin family based on the analysis of the number, area of neuron bodies and volumetric characteristics of the kisspeptin-producing nuclei of the hypothalamus.

MATERIALS AND METHODS: We studied 50 frontal paraffin sections of KPNs of 8 intact sexually mature male rats obtained as a result of a standard technique for their preparation and staining by the Nissl method. As a result, we carried out volumetric reconstruction of the largest nucleus of the arcuate complex — the medial arcuate nucleus and the large periventricular nucleus, after which the number and area of neurosecretory cell bodies were determined in 5 frontal planes of these nuclei. To determine the proportion of kisspeptin-producing neurons in the total number of neurons in the kisspeptin-producing nuclei of the hypothalamus, we also performed the subsequent quantitative and morphometric characterization of their kisspeptin-producing neurons (after immunohistochemical staining, the identification of kisspeptin-kisspeptin granules. Statistical data processing was performed using the GraphPad PRISM 6.0 program, determining and lower quartiles. Differences were considered significant at p < 0.01.

RESULTS: Subdivisions of the nuclei, which are the main source of these regulatory proteins, have been identified. The caudal part of the medial arcuate nucleus (at the level of bregma –3.6 mm) and the anterior part of the periventricular nucleus (at the level of bregma –0.2 mm) are subdivisions of the corresponding kisspeptin-producing nuclei of the hypothalamus of the kisspeptin-producing nuclei of the hypothalamus, containing the largest number of neurosecretory cells and the bodies of their largest largest area. The number and area of neurons in the left-sided and right-sided parts of the hypothalamic kisspeptin-producing nuclei of the hypothalamus did not differ significantly. In this regard, the listed left-sided and right-sided subdivisions of the kisspeptin-producing kisspeptin-producing nuclei of the hypothalamus of the were proposed as standards for their subsequent morphological studies, which are important for assessing the effectiveness of therapeutic correction of various forms of hypogonadism.

CONCLUSIONS: The left-sided and right-sided caudal parts of the medial arcuate hypothalamic nucleus and the anterior parts of the periventricular hypothalamic nucleus are proposed as a reference for their subsequent morphological studies related to the evaluation of the effectiveness of therapeutic correction of various forms of hypogonadism. as the main sources of regulatory proteins of the kisspeptin family.