Basic classical, peptidergic and nitrergic innervation pattern of human nasal glands--a histochemical and immunohistochemical study]

BACKGROUND: Seromucous glands are important components of the human nasal mucosa. The innervation patterns are relevant for understanding the control of the different physiological and pathophysiological glandular functions. Beside classic neurotransmitters some neuropeptides seem to influence the glandular secretion. METHODS: Tissue samples of 35 human inferior turbinates were taken during nasal surgery and preserved. Serial cryosections or paraffin sections were cut and incubated with antibodies either to Tyrosinhydroxilase or to Vasoactive Intestinal Peptide (VIP), Calcitonin Gene-Related Peptide (CGRP) and endothelial or brain Nitric Oxide Synthase (eNOS or bNOS). AChE- and NADPH-diaphorase-histochemistry were performed. RESULTS: Immunoreactive nerve fibers were found in the periglandular tissue around the acini, ducts and in the periglandular connective tissue. The density of positive immunoreactive structures depended on the different antibodies. VIP was found in contact to acinus cells, CGRP in the connective tissue around glandular cells. Particular immunoreactions to VIP and CGRP-antibodies could be detected near the glandular duct system. The eNOS-reactions were found in small capillaries near the acinus cells. CONCLUSIONS: Immunohistochemical and histochemical methods allow a detailed marking of nerval structures in nasal mucosa. The localization of neurons with different neurotransmitters and neuropeptides in the periglandular tissue confirms the direct nerval control of the diverse glandular functions. The detection of bNOS- and NADPH-d-positive structures around glandular cells and eNOS in the endothelium of periglandular capillaries suggests that NO takes an additional part in the regulation of nasal glands.