Disease relevance of Hal

• This report presents results of a study on the effects of TPA on epidermal histidase (L-histidine ammonia lyase), an enzyme found in normal epidermis but not in dermis or in mouse squamous cell carcinomas [1].
• Inducibility of thymic lymphomas in female Hsd: (ICR)BR mice following subcutaneous injection of ethyl- and isopropyl methanesulfonate [2].
• Mousepox was identified in a single mouse-holding room in early 1999 after a group of 20 CAF1/Hsd mice were inoculated SC with a killed murine spindle cell tumor line, S1509A [3].

High impact information on Hal

• Histidinemia in mice and in humans is an autosomal recessive disorder of histidine metabolism that leads to high-histidine levels in both plasma and urine and is caused by a lack of hepatic histidine-alpha-deaminase (histidase) [4].
• In comparison, there was no change in urinary histidine levels in the control group of histidase-deficient mice treated with isolated liver cells from mice lacking histidase (statistical comparison between the two groups, P < .003, two-way ANOVA) [4].
• Histologically, ectopic liver tissue was seen in the peritoneum in association with abdominal wall, pancreas, and peritoneal connective tissue; immunohistochemical evidence showed expression of histidase in the ectopic liver tissue in the active transplant group [4].
• Examination of multiple phases of auditory processing using auditory-evoked potentials (AEPs) following acute ketamine (0, 5, and 20 mg/kg) treatment revealed C3H/HeHsd mice to be most vulnerable to ketamine-induced alterations in AEPs, whereas FVB/Hsd mice exhibited the least electrophysiological sensitivity to ketamine [5].
• Brain catecholamine analyses indicated that ketamine decreased hippocampus epinephrine levels in C3H/HeHsd but elevated hippocampus epinephrine levels in FVB/Hsd, suggesting one potential mechanism for AEP vulnerability to ketamine [5].

Chemical compound and disease context of Hal

• Isopropyl methanesulfonate (IMS), a direct-acting SN1 alkylating agent, induced thymic lymphomas in 29 of 30 female Hsd: (ICR)BR mice by the 139th day following once a week subcutaneous injections at a dose of 10 mumol/mouse [2].

Biological context of Hal

• Identification of the mutation in murine histidinemia (his) and genetic mapping of the murine histidase locus (Hal) on chromosome 10 [6].
• Male MF1-nu/nu/Ola/Hsd nude mice, maintained in a gnotobiotic environment, were dosed i.p. with either 50, 100 or 200 mg/kg 2-bromoethanamine (BEA) hydrobromide to induce a model papillary necrosis [7].

Anatomical context of Hal

• The homologous locus in the mouse (Hal) was mapped to region 10C2----D1 by in situ hybridization, using a cell line from a mouse homozygous for a 1.10 Robertsonian translocation [8].
• Expression of the R322Q allele in COS cells resulted in proportionately reduced amounts of histidase protein and activity compared to the wildtype allele [6].

Associations of Hal with chemical compounds

• Based on results of the acute study, the immediate and lasting effects of chronic low-dose ketamine on AEPs were examined among C3H/HeHsd (sensitive) and FVB/Hsd (insensitive) mice [5].
• L-histidine ammonia-lyase (histidase) was encapsulated within cellulose nitrate artificial cells, and its kinetic parameters were evaluated [9].

Other interactions of Hal

• Hal maps approximately 4 cM distal to the insulin-like growth factor-1 locus and approximately 10 cM proximal to steel [6].
• Variation in activity of the main histidine catabolic enzymes (histidase, urocanase, and aminotransferase) has been surveyed using inbred strains of mice (C57BL, DBA, Peru, SM, and SWR) [10].

Analytical, diagnostic and therapeutic context of Hal

• Measurements of the relative rates of histidase synthesis by combined radiochemical and immunological techniques showed that the relative rate of synthesis was closely correlated with the amount of enzyme present [11].
• In vitro experiments to evaluate the feasibility of microencapsulated histidase for possible experimental therapy in histidinemia were carried out [9].

References