1.25-Dihydroxyvitamin D3 receptor is partly colocalized with oxytocin immunoreactivity in neurons of the male rat hypothalamus.
With receptor immunocytochemistry, neurons receptive for the steroidhormone 1.25-dihydroxyvitamin D3 have been observed in hypothalamic nuclei. In the present paper we report that a fraction of 1.25-dihydroxyvitamin D3 receptor (VDR) immunoreactive neurons in the hypothalamus of male rats are immunoreactive for oxytocin (OT), suggesting a direct genomic action of this steroid on OT expression. While only 10% of neurons with OT immunofluorescence in the periventricular nucleus contained nuclear VDR immunostaining, up to 50% of the OT neurons in the supraoptic nucleus and 30% in the magnocellular portion of the paraventricular nucleus were VDR positive. VDR immunostaining in the magnocellular nuclei was in many cases confined to the perinuclear cytoplasm. We assume that 1.25-dihydroxyvitamin D3 has effects on hypothalamic peptidergic systems similar to other steroid hormones.
Prüfer
K
K
Institut für Anatomie II, Friedrich-Schiller Universität Jena, Germany.
Jirikowski
G F
GF
D000818:Animals; D007031:Hypothalamus; D008297:Male; D009474:Neurons / Q000166:cytology / Q000378:metabolism*; D010121:Oxytocin / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D018167:Receptors, Calcitriol / Q000378:metabolism*
D018167:Receptors, Calcitriol; D010121:Oxytocin