The occurrence of antigen reacting with antibody to porcine neurophysin

Abstract

1. Antiserum was raised in rabbits to neurophysin prepared from posterior pituitaries of pigs. The presence of antibody reacting with porcine neurophysin was demonstrated in precipitation, gel diffusion and immunoelectrophoretic tests. 2. The antibody was species specific and did not react with protein from rat, bovine or guinea‐pig neurohypophyses. 3. The occurrence of antigen reacting with anti‐neurophysin serum was demonstrated in acetic acid extracts of porcine kidney but there was no evidence for the presence of antigen in extracts of liver or spleen prepared in the same way. 4. Protein fractions (‘N‐fractions’) from various organs and tissues of pigs were obtained by the same methods used to prepare neurophysin from posterior pituitaries and were tested for antigenicity in reaction with neurophysin antibody. N‐fractions from kidney, uterus, mammary gland and serum contained antigen while fractions from liver, spleen, brain and skeletal muscle did not react with the anti‐neurophysin serum.

The distribution of proteins that bind neurohypophysial hormones

“…A similar pattern was evident in the behaviour of these protein fractions as antigens in reaction with anti-neurophysin serum: protein obtained from the target organs and serum gave a positive reaction with the antiserum while protein from the other organs (i.e. liver, spleen, brain and skeletal muscle) failed to react with the antiserum (see Ginsburg & Jayasena, 1968). M. GINSBURG AND K. JAYASENA Binding of vasopressin and oxytocin to plasma protein was suggested three decades ago (Heller, 1937) when it was shown that the ultra-filtrability of neurohypophysial principles was decreased when pituitary extracts were mixed with blood.…”

“…(c) The protein fractions react with antiserum raised against porcine neurohypophysial neurophysin, giving a reaction of identity in the gel diffusion test, and a single band of precipitation on immuno-electrophoresis (see Ginsburg & Jayasena, 1968).…”

“…The preparation and characterization of antibody to porcine neurophysin (the carrier protein for oxytocin and vasopressin in the neurohypophysis) has been described by Ginsburg & Jayasena (1968). While the antibody showed a high degree of species specificity, protein with antigenic properties similar to neurohypophysial neurophysin was also found in extracts of porcine serum and of those organs (kidney, uterus and mammary gland) on which the principal effects of oxytocin and vasopressin are seen.…”

Localization of neurophysin-II in the hypothalamo-neurohypophysical system of the pig by immunofluorescence histochemistry

“…The exceptionally high V/O ratio they observed in the SON suggests that this nucleus is exclusively concerned with the elaboration of vasopressin. Ginsburg & Jayasena (1968 a) have prepared antisera to a porcine neurophysin preparation which has later been shown to consist of three components (Ginsburg,Burford & Thomas 197°) • Their antisera cross-reacted with protein components isolated from porcine kidney, uterus, mammary gland and serum. The protein components from kidney and serum also bound lysine vasopressin (Ginsburg & Jayasena 1968 b).In the present study, ant physin-11 did not cross-react with kidney and it is likely that the hormone-binding protein fraction from kidney differs from porcine neurophysin-n in molecular structure.…”