Antisera against rat recombinant histidine decarboxylase: immunocytochemical studies in different species.

Histamine is involved in many important biological processes such as allergic reactions, gastric acid secretion and neurotransmission. The formation of histamine is catalysed by the enzyme histidine decarboxylase. In order to understand the role of histamine in different tissues, information about the cellular localisation of the decarboxylase is important. However, the availability of antisera against the enzyme, which can be used in immunocytochemical techniques, has so far been limited, mainly due to the difficulties in purifying sufficient amounts of histidine decarboxylase from various tissues. In the present study we describe the use of antisera raised against rat recombinant histidine decarboxylase to localise the enzyme immunocytochemically in the gastric mucosa of different mammals and submammalian vertebrates. The antisera specifically stained histidine decarboxylase-immunoreactive cells in the gastric mucosa of not only rat, but also of species like frog, chicken, mouse and dog. This is the first report describing the immunocytochemical distribution of the decarboxylase in the gastric mucosa of species other than rat. These antisera are likely to become valuable tools for further studies of the immunocytochemical localisation of histidine decarboxylase.