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Updated: Jul 22, 2026

Spectral Confocal Imaging of Fluorescently tagged Nicotinic Receptors in Knock-in Mice with Chronic Nicotine Administration
Published on: February 10, 2012
Effects of nicotine on the concentration of native and cryptic Met- and Leu-enkephalin in peripheral tissues
K Pierzchała-Koziec1, G R Van Loon
1Department of Animal Physiology, Academy of Agriculture, Cracow, Poland.
Abstract:
The distribution of the native pentapeptides, Met- and Leu-enkephalin, and their cryptic forms (larger enkephalin-containing peptides) in adrenal medulla, spleen, lung, salivary gland, vas deferens, heart, duodenum and jejunum were determined by radioimmunoassay. The proportion of total Met- and Leu-enkephalin represented by native pentapeptide varied markedly among these tissues. Also, the distribution of native and cryptic Met-enkephalin was distinct from that of Leu-enkephalin. Repeated short-term administration of nicotine, 0.1 mg/kg i.p. six times at 30 min intervals, produced significant changes in native and cryptic Met-enkephalin in adrenal medulla, jejunum, vas deferens, spleen and heart. This regimen of nicotine also affected the concentration of Leu-enkephalin in adrenal medulla, jejunum and spleen.
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