Morabito E, Corsico N, Marzo A, Arrigoni Martelli E
Department of Pharmacology, Sigma-Tau S.p.A., Pomezia, Roma, Italy.
Arzneimittelforschung. 1994 Aug;44(8):965-8.
Serum concentration and urinary excretion of levocarnitine (L-carnitine, CAS 541-15-1) family components were evaluated in a Wistar derived strain of genetically diabetic rats BB/BB, in comparison with normal Wistar rats, and their control rats BB/WB of both sexes. BB/BB diabetic animals have lower serum concentration of total-L-carnitine (TC), L-carnitine (LC), acetyl-L-carnitine (ALC), and short chain L-carnitine esters (SCLCE) than both the strains of non-diabetic rats, as previously observed in streptozotocin diabetic rats. No or marginal variations between control and diabetic rats were detected in cumulative urinary excretion of L-carnitine family components. A strain difference was observed between Wistar and BB/WB non-diabetic rats, BB/WB showing higher serum concentration and lower cumulative urinary excretion of LC and TC than Wistar animals. Renal clearance of L-carnitine components proved to be markedly higher in BB/BB diabetic rats, as previously shown in streptozotocin rats. The reduction of serum concentration of the carnitines endogenous pool may explain this finding. The lack of an increased urinary excretion of L-carnitine components in diabetic animals despite the high increase of diuresis suggests that the saturable tubular reabsorption of L-carnitine family components also in diabetes is the primary mechanism to preserve the homeostatic equilibria of the L-carnitine family, the variation in serum concentration being attributable to the complex systemic metabolic alterations typical of diabetes. In agreement with previous investigations, male animals of all the strains showed higher serum concentration and urinary excretion of L-carnitine components as compared to females.
在源自Wistar的遗传性糖尿病大鼠BB/BB品系中，评估了左旋肉碱（L-肉碱，CAS 541-15-1）家族成分的血清浓度和尿排泄情况，并与正常Wistar大鼠及其对照大鼠BB/WB（雌雄均有）进行了比较。与非糖尿病大鼠的两个品系相比，BB/BB糖尿病动物的总L-肉碱（TC）、L-肉碱（LC）、乙酰-L-肉碱（ALC）和短链L-肉碱酯（SCLCE）的血清浓度较低，这与先前在链脲佐菌素诱导的糖尿病大鼠中观察到的情况一致。在L-肉碱家族成分的累积尿排泄方面，未检测到对照大鼠和糖尿病大鼠之间有差异或仅有微小差异。在Wistar和BB/WB非糖尿病大鼠之间观察到品系差异，BB/WB大鼠的LC和TC血清浓度高于Wistar动物，而累积尿排泄则较低。正如先前在链脲佐菌素诱导的大鼠中所显示的那样，BB/BB糖尿病大鼠的L-肉碱成分肾清除率明显更高。内源性肉碱池血清浓度的降低可能解释了这一发现。尽管糖尿病动物的尿量大幅增加，但L-肉碱成分的尿排泄并未增加，这表明糖尿病时L-肉碱家族成分的肾小管重吸收具有饱和性，这是维持L-肉碱家族体内平衡的主要机制，血清浓度的变化归因于糖尿病典型的复杂全身代谢改变。与先前的研究一致，所有品系的雄性动物与雌性动物相比，L-肉碱成分的血清浓度和尿排泄更高。
