Propressophysin is present in neurones at multiple sites in Wistar and homozygous Brattleboro rat brain.

Vasopressin (VP) is synthesized as propressophysin, containing also neurophysin (NP) and C-terminal glycopeptide (CPP), within the hypothalamo-neurohypophyseal system (HNS). Recently, VP and NP-immunoreactive cells were demonstrated in other rat brain nuclei. Here we report CPP immunoreactivity in perikarya in these nuclei. Within the homozygous Brattleboro rat, known to be deficient in neuronal VP production, no CPP immunoreactivity was seen in these nuclei. However, intense VP and CPP immunoreactivity was present in solitary cells (52.2 +/- 3.3 per rat) and fibres within the HNS.