Yadav R N
Department of Life Sciences, Dibrugarh University, Assam, India.
Cell Biochem Funct. 1988 Jul;6(3):197-202. doi: 10.1002/cbf.290060308.
The activity and hormonal regulation of NAD- and NADP-linked isocitrate dehydrogenase (EC.1.1.1.41 and EC.1.1.1.42, respectively) in the brain, liver and kidney cortex of female rats of various ages was investigated. The activity of NAD-ICDH of brain was greater than extramitochondrial (-c) or intramitochondrial (-m) NADP-ICDH. In contrast, liver c-NADP-ICDH was much higher than NAD- or m-NADP-ICDH, whereas in kidney cortex the activity of m-NADP-ICDH is dominant over both NAD- and c-NADP-ICDH in all the age group of rats studied. The activity of the NAD-ICDH of brain and all the enzymes of liver and kidney cortex increases until adulthood (33-weeks) and decreases thereafter in old rats (85-weeks). In brain c-NADP-ICDH was much higher in immature (6-weeks) rats and decreases with increasing age of the animal, whereas m-NADP-ICDH showed no significant change with the age of the rats. Bilateral ovariectomy decreases the level of all the three forms of enzyme in all the tissues of 6-, 13- and 33-week rats but failed to show any significant effect in 85-week old rats. Exogenous administration of estradiol induces all the three forms of enzyme in all the tissues of ovariectomized rats. The degree of response is tissue- and age-specific.
研究了不同年龄雌性大鼠脑、肝和肾皮质中NAD - 异柠檬酸脱氢酶（分别为EC.1.1.1.41）和NADP - 异柠檬酸脱氢酶（分别为EC.1.1.1.42）的活性及激素调节。脑内NAD - ICDH的活性高于线粒体外（-c）或线粒体内（-m）的NADP - ICDH。相反，肝中的胞质NADP - ICDH远高于NAD - ICDH或线粒体内NADP - ICDH，而在肾皮质中，在所有研究年龄组的大鼠中，线粒体内NADP - ICDH的活性均高于NAD - ICDH和胞质NADP - ICDH。脑内NAD - ICDH以及肝和肾皮质中所有酶的活性在成年期（33周）前增加，此后在老年大鼠（85周）中降低。在脑中，未成熟（6周）大鼠的胞质NADP - ICDH远高于成熟大鼠，且随着动物年龄的增加而降低，而线粒体内NADP - ICDH的活性则未随大鼠年龄的增长而发生显著变化。双侧卵巢切除降低了6周、13周和33周龄大鼠所有组织中这三种酶的水平，但对85周龄大鼠未显示出任何显著影响。对去卵巢大鼠各组织外源性给予雌二醇可诱导这三种酶的产生。反应程度具有组织和年龄特异性。
