Adrenoleukodystrophy (ALD) and adrenomyeloneuropathy (AMN) are related X-linked disorders characterized by adrenal, gonadal, and nervous system dysfunction. While the pathologic finding common to these tissues appears to be the accumulation of excessive amounts of very long chain fatty acids, the mechanism leading to functional impairment in these tissues is unclear. Measurements of fluorescence polarization (P), using the lipid probe diphenylhexatriene, demonstrate a highly significant increase in the microviscosity of erythrocyte membranes in affected patients (P = 0.286 +/- 0.012) vs. normals (P = 0.239 +/- 0.020). Analyses of these membranes by gas-liquid chromatography revealed 1.9-, 1.6-, and 1.3-fold increases above normal values in the C25:0, C26:0, and C27:0 fatty acids, respectively. These observations are compatible with previously obtained data in animals that correlate membrane microviscosity with the number of hormone receptors in target tissues. The present data support the thesis that a decrease in responsiveness to trophic hormones in ALD and AMN is secondary to changes in the membrane microviscosity of the target tissues and suggest a mechanism by which adrenal and gonadal failure occur in such patients.
R A Knazek, W B Rizzo, J D Schulman, J R Dave
Usage data is cumulative from March 2022 through March 2023.
Usage information is collected from two different sources: this site (JCI) and Pubmed Central (PMC). JCI information (compiled daily) shows human readership based on methods we employ to screen out robotic usage. PMC information (aggregated monthly) is also similarly screened of robotic usage.
Various methods are used to distinguish robotic usage. For example, Google automatically scans articles to add to its search index and identifies itself as robotic; other services might not clearly identify themselves as robotic, or they are new or unknown as robotic. Because this activity can be misinterpreted as human readership, data may be re-processed periodically to reflect an improved understanding of robotic activity. Because of these factors, readers should consider usage information illustrative but subject to change.