Kinetics of Cu2+ inhibition of Na+/K(+)-ATPase.
نویسندگان
چکیده
The interaction of Cu2+ with enzymatic activity of rabbit kidney Na+/K(+)-ATPase was studied in media with buffered, defined free Cu2+ levels. The IC50-values are 0.1 mumol/l for Na+/K(+)-ATPase and 1 mumol/l for K(+)-pNPPase. Dithiothreitol (DTT) reverses the inhibitory effect of Cu2+ in vitro. Cu2+ exerts non-competitive effects on the enzyme with respect to Na+, K+, ATP or pNPP, but has a mixed-type inhibitory effect with respect to Mg2+. It is concluded that the appreciation of the inhibitory effect of Cu2+ on this enzyme requires carefully composed assay media that include a buffer for Cu2+, and that the IC50-values calculated according to this model indicate that Cu2+ may be more toxic than previously anticipated.
منابع مشابه
ENZYME INHIBITION BY HERBAL MOLLUSCICIDES IN THE NERVOUS TISSUE OF THE SNAIL LYMNAEA ACUMINATA
The effect of Annona squamosa, Lawsonia inermis and their combination with other herbal molluscicides were studied on different enzyme activity in the nervous tissue of Lymnaea acuminata. Twenty-Four hour in vivo exposure to 40% and 80% of 24 h LC50 of plant derived molluscicides and their combination with other molluscicides such as Cedrus deodara, Azadirachta indica oil, Allium sativum, Polia...
متن کاملO-10: A Marked Animal-Vegetal Polarity in The Localization of Na+,K+-ATPase Activity and Its Down-Regulation Following Progesterone-Induced Maturation
Background: Polarized cells are key to the process of differentiation. Xenopus oocyte is a polarized cell that has complete blue-print to differentiate 3 germ layers following fertilization, as key determinant molecules (Proteins and RNAs) are asymmetrically localized. The objective of this work was to localize Na+, K+-ATPase activity along animal-vegetal axis of polarized Xenopus oocyte and fo...
متن کاملComparative study on the effect of cinnamon and clove extracts and their main components on different types of ATPases.
The effect of the commonly used spice extracts cinnamon and clove and their main ingredients on the activity of various ATPases were investigated. Water extracts of both spices inhibited the activity of rat liver Na+/K+ ATPase, and Cu2+-ATPase, but stimulated F0F1ATPase. Similar effects were obtained with cinnamaldehyde and eugenol the major components of cinnamon and clove, respectively with e...
متن کاملA New Method to Estimate Inhibition Percentage of Endogenous Digitalis in Patients with Pre-eclampsia
Background: Pre-eclampsia is an idiopathic pregnancy disorder characterized by appearance proteinuria and hypertension, with poorly understood etiology. It has been linked to a variety of system abnormalities, including ion transport disorders in neonatal, maternal, and placental cell lines. A new method was described to evaluate the inhibition percentage of endogenous digitalis in plasma of pr...
متن کاملEffect of different levels of salinity on immunolocalization of Na+-K+ ATPase and Aquaporin 3 in kidney of common carp Cyprinus carpio
Cyprinus carpio is a stenohaline species but can tolerate some ranges of changes in environmental salinities, so histomorphological methods and Na+-K+ ATPase and Aquaporin 3 immunohistochemistry were performed on common carp kidney as an osmoregulatory organ in experimental groups and control in order to investigate their possible roles during salinity challenge. Five groups of fish (n=25) with...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- Toxicology letters
دوره 87 1 شماره
صفحات -
تاریخ انتشار 1996