کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
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1923466 | 1048897 | 2014 | 6 صفحه PDF | دانلود رایگان |
Chicken d-serine dehydratase (DSD) degrades d-serine to pyruvate and ammonia. The enzyme requires both pyridoxal 5′-phosphate and Zn2+ for its activity. d-Serine is a physiological coagonist that regulates the activity of the N-methyl-d-aspartate receptor (NMDAR) for l-glutamate. We have recently found in chickens that d-serine is degraded only by DSD in the brain, whereas it is also degraded to 3-hydroxypyruvate by d-amino acid oxidase (DAO) in the kidney and liver. In mammalian brains, d-serine is degraded only by DAO. It has not been clarified why chickens selectively use DSD for the control of d-serine concentrations in the brain. In the present study, we measured DSD activity in chicken tissues, and examined the cellular localization of DSD using a specific anti-chicken DSD antibody. The highest activity was found in kidney. Skeletal muscles and heart showed no activity. In chicken brain, cerebellum showed about 6-fold-higher activity (1.1 ± 0.3 U/g protein) than cerebrum (0.19 ± 0.03 U/g protein). At the cellular level DSD was demonstrated in proximal tubule cells of the kidney, in hepatocytes, in Bergmann-glia cells of the cerebellum and in astrocytes. The finding of DSD in glial cells seems to be important because d-serine is involved in NMDAR-dependent brain functions.
Journal: Acta Histochemica - Volume 116, Issue 5, June 2014, Pages 702–707