Calbindin D28k and calretinin in oxytocin and vasopressin neurons of the rat supraoptic nucleus. A triple-labeling immunofluorescence study.
The aim of the present study was to examine quantitatively whether two calcium-binding proteins, calbindin D28k and calretinin, are localized in oxytocin and vasopressin neurons of the supraoptic nucleus of the male rat. We used a triple-labeling immunofluorescence method with a confocal laser scanning microscope. Of the oxytocin-labeled cells, 70% were stained for both calbindin D28k and calretinin, 15% were stained for only calbindin D28k, 13% were stained for only calretinin, and 2% were stained for neither protein. Of the vasopressin-labeled cells, 73% were stained for neither calbindin D28k nor calretinin, 21% were stained for only calbindin D28k, 4% were stained for only calretinin, and 2% were stained for both proteins. Calbindin D28k and calretinin have been shown previously to contribute to calcium homeostasis by buffering [Ca2+]i. Therefore, these findings suggest that most of the oxytocin neurons may have a higher Ca(2+)-buffering capacity than most of the vasopressin neurons.
Arai
R
R
Department of Anatomy, Fujita Health University School of Medicine, Toyoake, Aichi, Japan. rarai@fujita-hu.ac.jp
Jacobowitz
D M
DM
Hida
T
T
D000818:Animals; D064092:Calbindin 1; D064032:Calbindin 2; D064026:Calbindins; D002118:Calcium / Q000378:metabolism; D005455:Fluorescent Antibody Technique; D008297:Male; D018613:Microscopy, Confocal; D009419:Nerve Tissue Proteins / Q000378:metabolism*; D009474:Neurons / Q000378:metabolism; D010121:Oxytocin / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D064030:S100 Calcium Binding Protein G / Q000378:metabolism*; D013495:Supraoptic Nucleus / Q000166:cytology / Q000378:metabolism*; D014667:Vasopressins / Q000378:metabolism
C576500:Calb1 protein, rat; C576512:Calb2 protein, rat; D064092:Calbindin 1; D064032:Calbindin 2; D064026:Calbindins; D009419:Nerve Tissue Proteins; D064030:S100 Calcium Binding Protein G; D014667:Vasopressins; D010121:Oxytocin; D002118:Calcium