reductase

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reductase

 [re-duk´tās]
an enzyme that catalyzes a chemical reduction.
5α-reductase an enzyme that catalyzes the irreversible reduction of testosterone to dihydrotestosterone.

re·duc·tase

(rē-dŭk'tās),
An enzyme that catalyzes a reduction; because all enzymes catalyze reactions in either direction, any reductase can, under the proper conditions, behave as an oxidase and vice versa, hence the term oxidoreductase. For individual reductases, see the specific names.
Synonym(s): reducing enzyme

reductase

(rĭ-dŭk′tās′, -tāz′)
n.
Any of various enzymes that catalyze the reduction of an organic compound.

reductase

A generic term for any enzyme that catalyses a chemical reduction reaction.

re·duc·tase

(rĕ-dŭk'tās)
An enzyme that catalyzes a reduction; because all enzymes catalyze reactions in either direction, any reductase can, under the proper conditions, behave as an oxidase and vice versa; hence the term oxidoreductase.

reductase

an ENZYME that catalyses the REDUCTION of a compound.
References in periodicals archive ?
Measurement of this ratio assesses for 5a-reductase enzyme activity.
Testosterone is converted to the more potent androgen, 5a-DHT, by the 5a-reductase enzyme within the prostate.
Wilson et al., Steroid 5a-Reductase 2 Deficiency, 14 endocrine Rev.
Compound Inhibitory to Rat Liver 5a-reductase from Tropical Commercial Wood Species: Resveratrol Trimmer from Melapi (Shorea sp.) heartwood.
Alpha blockers and the 5a-reductase inhibitors can also be given together, because some data suggest that using the drugs together is better than using either one alone.
After an appropriate informed consent-talk (Doc trained as a surgeon), she began a 5a-reductase inhibitor, saw palmetto extract (SPE) 320 mg twice daily.
(74) SPE inhibits both types 1 and 2 5a-reductase. (77,78) Its action on type-1 5[alpha]-R is most relevant for PMDD, since the human brain uses this isoform.
5a-Reductase Inhibition Prevents the Luteal Phase Increase in Plasma Allopregnanolone Levels and Mitigates Symptoms in Women with Premenstrual Dysphoric Disorder.
Reduced bone mass and muscle strength in male 5a-reductase type 1 inactivated mice.
5a-Reductase enzymes may not be good targets for prostate cancer chemo-prevention, despite the biologically sound basis for their use.
As expected in healthy adults with statistically indistinguishable body mass index values [mean (SD): 22.8 (1.7) for men and 21.9 (1.8) kg/[m.sup.2] for women], GC3 excretion was higher in men than women [10.1 (3.2) and 6.9 (2.3) mg/day, respectively, P <0.01], as was 5a-reductase [1.3 (0.5) and 0.9 (0.4), P <0.05], whereas plasma leptin was lower in men than in women [2.8 (1.6) and 7.6 (4.9) [micro]g/L, respectively, P <0.01].
Because there is little 5a-reductase activity in skeletal muscle [10], testosterone and possibly circulating DHT appear to be the key hormones for androgen action.