Colocalization of oxytocin and neurophysin-I/II and of vasopressin and neurophysin-III in neurons of the sheep hypothalamus. An immunohistochemical study.

Antisera raised against, oxytocin, vasopressin and ovine neurophysins-I, -II and -III (oN-I, oN-II and oN-III respectively) were used in association with the immunohistochemical procedure to stain neurons of the formalin-fixed sheep hypothalamus. Cells that stain for oxytocin also contain oN-I and oN-II and differ from those that stain for vasopressin and oN-III. The observations support our earlier findings in the sheep that oxytocin- and vasopressin-related events are accompanied by the release of oN-I/II and oN-III respectively.