KISSPEPTIN - A NOVEL PEPTIDE IN REPRODUCTION

Since kisspeptin appeared on the stage of endocrinology of reproduction in 2003, its role as a key trigger of the complex aspects of reproduction and especially of the stimulation of gonadotrophin releasing hormone/luteinising hormone in females, was progressively explored and documented. The family of peptides called kisspeptins are products of KiSS-1 gene and are able to bind and activate GRR54 receptor. The role of KiSS-1/GPR54 ligand-receptor system working generally in the hypothalamus, was described in many species of both sexes including humans. In presented review, the key role of this system in the activation of the hypothalamo-pituitary-gonadal (HPG) axis in females from puberty to ovulation was characterized. It is believed, that KiSS-1 system plays an essential role in the timing of puberty onset, what is additionally related to the modulatory action of metabolic and environmental factors. The effect of kisspeptin on dynamic changes in the HPG axis in mature females during the oestrous cycle and its participation in the negative and positive feedback effects of sex hormones on gonadotrophin secretion was also discussed. Finally, investigations concerning the localization and morpho-physiological activity of kisspeptin neurons in the the hypothalamus of mammals and their contacts with GnRH neurons were presented.