V [[možgani]]h encim serin racemaza iz L-serina sintetizira [[enantiomer]] D-serin, ki je nevromodulator -– vpliva na prenos signalov med celicami centralnega[[osrednje živčnegaživčevje|osrednjega sistemaživčevja]],<ref>{{cite journal | authors = Mothet JP, Parent AT, Wolosker H, Brady RO, Linden DJ, Ferris CD, Rogawski MA, Snyder SH | title = D-serine is an endogenous ligand for the glycine site of the N-methyl-D-aspartate receptor | journal = Proceedings of the National Academy of Sciences of the United States of America | volume = 97 | issue = 9 | pages = 4926–31 | date = Apr 2000 | pmid = 10781100 | pmc = 18334 | doi = 10.1073/pnas.97.9.4926 | bibcode = 2000PNAS...97.4926M }}</ref> pa tudi v [[hrustanec|hrustancu]]<ref>{{cite journal | authors = Takarada T, Hinoi E, Takahata Y, Yoneda Y | title = Serine racemase suppresses chondrogenic differentiation in cartilage in a Sox9-dependent manner | journal = Journal of Cellular Physiology | volume = 215 | issue = 2 | pages = 320–8 | date = May 2008 | pmid = 17929246 | doi = 10.1002/jcp.21310 }}</ref> in [[ledvica]]h.<ref>{{cite journal | authors = Ma MC, Huang HS, Chen YS, Lee SH | title = Mechanosensitive N-methyl-D-aspartate receptors contribute to sensory activation in the rat renal pelvis | journal = Hypertension | volume = 52 | issue = 5 | pages = 938–44938–944 | date = Nov 2008 | pmid = 18809793 | doi = 10.1161/HYPERTENSIONAHA.108.114116 }}</ref> D-serin je v fazi testiranja za zdravljenje [[shizofrenija|shizofrenije]] in [[Amiotrofična lateralna skleroza|amiotrofične lateralne skleroze]].<ref>{{cite journal | authors = Balu DT, Li Y, Puhl MD, Benneyworth MA, Basu AC, Takagi S, Bolshakov VY, Coyle JT | title = Multiple risk pathways for schizophrenia converge in serine racemase knockout mice, a mouse model of NMDA receptor hypofunction | journal = Proceedings of the National Academy of Sciences of the United States of America | volume = 110 | issue = 26 | pages = E2400-9 | date = Jun 2013 | pmid = 23729812 | doi = 10.1073/pnas.1304308110 }}</ref><ref>{{cite journal | authors = Dunlop RA, Cox PA, Banack SA, Rodgers KJ | title = The non-protein amino acid BMAA is misincorporated into human proteins in place of L-serine causing protein misfolding and aggregation | journal = PLOS ONE | volume = 8 | issue = 9 | pages = e75376 | pmid = 24086518 | pmc = 3783393 | doi = 10.1371/journal.pone.0075376 }}</ref>
