title: Immunocytochemical evidence for the presence of an albumin-like substance in the rat pineal gland.
abstract: Two rabbits and two guinea pigs were immunized with arginine vasotocin (AVT) conjugated to bovine albumin with glutaraldehyde. Only one preparation of antiserum (anti-G 7) was of value. Anti-G 7 immunochemically defined the same rat pineal cells previously reported as presumptive AVT cells. However, absorption of anti-G 7 with bovine albumin inhibited the staining of the pineal cells demonstrating that they contained an albumin-like substance. Positive immunochemical staining of the rat pars nervosa suggested that anti-G 7 contained antibodies able to react with arginine vasopressin (AVP). Loss of a positive reaction in the posterior lobe on absorption of anti-G 7 with AVT or AVP confirmed this. However, the addition of AVT to anti-G 7 failed to inhibit the immunochemical staining of the pineal cells. This study reports the presence of an albumin-like substance in pineal cells previously described as presumptive AVT cells, and discusses possible explanations for the inability of anti-G 7 to recognize immunocytochemically the native AVT molecule. Confirmation of AVT in the pineal gland by immunocytochemistry must await the availability of more specific antisera.
mesh_terms: D000418:Albumins / Q000032:analysis*; D000818:Animals; D005455:Fluorescent Antibody Technique; D007106:Immune Sera; D008297:Male; D010870:Pineal Gland / Q000032:analysis*; D010903:Pituitary Gland, Anterior / Q000032:analysis; D010904:Pituitary Gland, Posterior / Q000032:analysis; D051381:Rats; D014668:Vasotocin / Q000032:analysis / Q000276:immunology
chemical_list: D000418:Albumins; D007106:Immune Sera; D014668:Vasotocin