Acrolein: a fixative for immunocytochemical localization of peptides in the central nervous system

Acrolein was examined as an alternative fixative to formaldehyde for immunocytochemical localization of neuropeptides in the rat brain. A brief (5 min) vascular perfusion with a 5% acrolein solution allowed the identification of thyrotropin-releasing hormone (TRH), vasoactive intestinal peptide (VIP), somatostatin (SRIF), neurotensin (NT), methionine enkephalin (Menk), adrenocorticotropic hormone (ACTH), tyrosine hydroxylase (TH), and luteinizing hormone-releasing hormone (LHRH) in fibers and perikarya within the central nervous system of the rat using the peroxidase-antiperoxidase (PAP) technique. Acrolein appears to be particularly valuable for immunocytochemistry, as it 1) stabilizes heterogeneous peptides and proteins rapidly and effectively, 2) retains antigenicity, and 3) preserves morphological detail.