In the other enzymatic reaction, methylcobalamin supports the methionine synthase reaction, which is essential for normal metabolism of folate. The folate-cobalamin interaction is pivotal for normal synthesis of purines and pyrimidines and the transfer of the methyl group to cobalamin is essential for the adequate supply of tetrahydrofolate, the substrate for metabolic steps that require folate. In a state of vitamin B12 deficiency, the cell responds by redirecting folate metabolic pathways to supply increasing amounts of methyltetrahydrofolate. The resulting elevated concentrations of homocysteine and MMA are often found in patients with low serum vitamin B12 and can usually be lowered with successful vitamin B12 replacement therapy. However, elevated MMA and homocysteine concentrations may persist in patients with cobalamin concentrations between 200 and 350 pg/mL. Supplementation with vitamin B12 during conditions of deficiency restores the intracellular level of cobalamin and maintains a sufficient level of the two active coenzymes: methylcobalamin and deoxyadenosylcobalamin. See also
Methylcobalamin
Cyanocobalamin
Adenosylcobalamin
 Vitamin B12
Cobalamin biosynthesis
Nitric oxide

References
External links
Hydroxocobalamin in the ChEBI database
"Hydroxocobalamin". Drug Information Portal. U.S. National Library of Medicine.
In the United States and other developed countries, the incidence is low, possibly fivefold less than that of schizophrenia. In developing countries, the incidence is substantially higher, especially for the subtype "With Good Prognostic Features". In some of these settings schizophreniform disorder may be as common as schizophrenia. References
External links
Strakowski SM (June 1994). "Diagnostic validity of schizophreniform disorder". Am J Psychiatry. 151 (6): 815–24. doi:10.1176/ajp.151.6.815. PMID 8184991. Clinical Trials in Schizophrenia, Schizoaffective, or Schizophreniform Disorder 
Schizophreniform Disorder Patient information