Tachykinin-, calcitonin gene-related peptide-, and protein gene product 9.5-immunoreactive nerve fibers in alveolar walls of mammals.
The presence and distribution of the presumed pan-neural marker protein gene product 9.5 (PGP)- and peptide-immunoreactive (ir) nerve fibers in alveolar walls of various species was investigated by light microscopic single and double staining immunohistochemistry. PGP-, tachykinin (TK)-, and calcitonin gene-related peptide (CRGP)-ir fibers were sparsely distributed in a similar pattern in alveolar walls of all species investigated. No vasoactive intestinal peptide-, peptide histidine isoleucine-, galanin-, and opioid-ir nerve fibers could be detected. PGP-ir fibers outnumbered those staining for TKs and CGRP. There was partial coexistence of PGP and TK as well as of TK and CRGP. PGP-, TK-, and CGRP-ir fibers were in close spatial relationships to the cells building up the alveolar walls and to alveolar capillaries. The function of PGP is unknown. TK- and CGRP-ir nerves in alveolar walls may be sensory and function as chemo-, stretch-, and/or immuno-receptors. TKs and CGRP released from alveolar fibers may influence the alveolar epithelium and the various non-epithelial alveolar cells, including immune cells. The alveolar TK and CGRP innervation may be of unrecognized importance in physiological and pathophysiological regulation of lung functions.
Nohr
D
D
Anatomical Institute, University of Mainz, F.R.G.
Weihe
E
E
D000818:Animals; D015415:Biomarkers; D015740:Calcitonin Gene-Related Peptide / Q000032:analysis*; D002415:Cats / Q000378:metabolism; D006224:Cricetinae; D004285:Dogs / Q000378:metabolism; D006168:Guinea Pigs / Q000378:metabolism; D008322:Mammals / Q000378:metabolism*; D008647:Mesocricetus / Q000378:metabolism; D009412:Nerve Fibers / Q000737:chemistry; D009479:Neuropeptides / Q000032:analysis*; D011650:Pulmonary Alveoli / Q000737:chemistry* / Q000294:innervation; D051381:Rats / Q000378:metabolism; D013045:Species Specificity; D015320:Tachykinins / Q000032:analysis*; D043222:Ubiquitin Thiolesterase
D015415:Biomarkers; D009479:Neuropeptides; D015320:Tachykinins; D043222:Ubiquitin Thiolesterase; D015740:Calcitonin Gene-Related Peptide