Pulmonary endocrine cells ofAymaraIndians fromtheBolivian Andes

Introduction Thereisevidence to suggestthatlife athighaltitude causes changes in thepopulation of pulmonary endocrinecells,possiblybecauseof exposure tochronic hypoxia. A studywas made ofthepopulations ofpulmonary endocrine cells inthreeAymaraIndians andthreeMestizos ofLa Paz(3600m), Bolivia, whichwere comparedwiththose infourwhitelowlanders. MethodsPulmonaryendocrinecells were immunolabelled forneurone specific enolaseand theirtwo major secretory products, gastrin releasing peptideand calcitonin, andtheirnumbersexpressed per cm2 oftissue section. ResultsNo differences inmorphology, number, content, or distribution of immunoreactive cells were foundwhen thenativehighlanders were compared withthelowlanders. Conclusions Ifchronic hypoxia as such exertsan influence on humanpulmonary endocrine cells itwas notapparentinthis morphological study.There was no increase ingastrin releasing peptide containing pulmonaryendocrine cells, such as havepreviously beenseen inpatients withpulmonaryhypertension characterisedby plexogenic pulmonaryarteriopathy. Thismay beduetothefactthatin plexogenic pulmonaryarteriopathy there isfreemigration ofsmoothmusclecells. Althoughthreeofthehighlanders inthis presentstudyshowedpulmonaryvascularremodelling, thiswas incontrast onlymodest.