𝔖 Bobbio Scriptorium
✦   LIBER   ✦

Effect of ischemia of the rabbit bladder on Ca-Mg-activated ATP-ase activity

✍ Scribed by Bülent Soyupak; Alan J. Wein; Robert M. Levin; Niels Haugaard

Publisher
John Wiley and Sons
Year
1996
Tongue
English
Weight
399 KB
Volume
15
Category
Article
ISSN
0733-2467

No coin nor oath required. For personal study only.

✦ Synopsis

This investigation is concerned with the effect of ischemia on the activity of Ca-Mgstimulated ATP-ase in rabbit bladder tissue. White New Zealand male rabbits were used for the experiments. Ischemia was produced by clamping of the vesical arteries. After 1 and 2 hours the clamps were removed, and the animals were sacrificed 2 days later. The bladders were removed, and the muscle and mucosal parts of the bladders were separated. In some experiments with 2-hour ischemia the animals were allowed to recover for 7 days. Homogenates were made of the muscle and mucosal tissue and separated by differential centrifugation into three parts: 1) an initial particulate fraction obtained by low-speed centrifugation; 2) a supernate fraction free of mitochondria; and 3) a mitochondrial-rich fraction. ATP-ase activity was determined in the different fractions in the presence of magnesium or calcium as the activating ion, and the results were expressed as nmols/mg proteidminute. The following results were obtained: with the supernates, ischemia was found to produce a marked inhibition of enzyme activity that was large and significant in muscle tissue after 1 hour and in mucosal tissue after 2 hours. Seven days after termination of 1 hour of ischemia, the ATP-ase activity of the muscle fraction had been partially restored towards normal. Activity of ATP-ase when measured in the particulate fraction was less sensitive to the effect of ischemia; a significant diminution of enzyme activity in preparations from muscle was seen only after 2 hours of ischemia, and no inhibition was observed with mucosal tissue. ATP-ase of muscle mitochondria was severely inhibited by ischemia, and the effect of 1 hour of ischemia was not reversed 7 days after the insult.

Mitochondria from mucosal tissue were affected to only a small extent by ischemia. In all cases, results were similar whether magnesium or calcium was used for activation of the enzyme.

📜 SIMILAR VOLUMES

Properties of Ca2+-Mg2+ ATP-ase in rabbi
Properties of Ca2+-Mg2+ ATP-ase in rabbit bladder muscle and mucosa: Effect of urinary outlet obstruction
✍ Niels Haugaard; Alan J. Wein; Binoy Chandy; Bulent Soyupak; Stephen A. Zderic; R 📂 Article 📅 1996 🏛 John Wiley and Sons 🌐 English ⚖ 413 KB 👁 1 views

The contractile response of the smooth muscle of the urinary bladder is dependent upon both the entrance of extracellular calcium through receptor-operated calcium channels and the stimulated release of calcium from the sarcoplasmic reticulum. In addition, partial outlet obstruction induces marked a

The effect of toxic discharges on ATP co
The effect of toxic discharges on ATP content in activated sludge
✍ Arretxe, M. ;Heap, J. M. ;Christofi, N. 📂 Article 📅 1997 🏛 John Wiley and Sons 🌐 English ⚖ 87 KB 👁 1 views

ATP measured by the luciferin-luciferase bioluminescence assay was used to examine the effect of toxic substances on whole microbial communities in activated sludge mixed liquor samples. The response of the microorganisms to toxicants is rapid using ATP reduction as the criterion. The sensitivity of

Stimulatory effect of regucalcin on ATP-
Stimulatory effect of regucalcin on ATP-dependent Ca2+ uptake activity in rat liver mitochondria
✍ Hiroko Takahashi; Masayoshi Yamaguchi 📂 Article 📅 2000 🏛 John Wiley and Sons 🌐 English ⚖ 191 KB 👁 1 views

The effect of Ca 2ϩ -binding protein regucalcin on Ca 2ϩ -ATPase activity in isolated rat liver mitochondria was investigated. The presence of regucalcin (0.1, 0.25, and 0.5 M) in the enzyme reaction mixture led to a significant increase in Ca 2ϩ -ATPase activity. Regucalcin significantly stimulated

The effect of pregnancy and contractile
The effect of pregnancy and contractile activity on bladder muscarinic receptor subtypes
✍ Edgar C. Baselli; Steven B. Brandes; Gary R. Luthin; Michael R. Ruggieri 📂 Article 📅 1999 🏛 John Wiley and Sons 🌐 English ⚖ 159 KB 👁 1 views

In the rabbit bladder, pregnancy and prolonged bladder contractions decrease both muscarinic receptor density and contractile response, whereas newborns show enhanced muscarinic contractile response. Although the M 2 receptor predominates in rabbit bladder, we and others have shown that the affinity

Effect of diltiazem and pinacidil on the
Effect of diltiazem and pinacidil on the response of the rabbit urinary bladder to repetitive stimulation and in vitro ischemia
✍ Robert M. Levin; Robert E. Leggett; Catherine Whitbeck; Patrick Horan 📂 Article 📅 1999 🏛 John Wiley and Sons 🌐 English ⚖ 125 KB 👁 1 views

The effect of repetitive stimulation, in the presence and absence of diltiazem or pinacidil, on the contractile responses of isolated strips of rabbit bladder detrusor to field stimulation and carbachol, after 2 hr of incubation in a medium that serves as an in vitro model of ischemia (oxygen and su

Effect of exogenous calmodulin and ATP o
Effect of exogenous calmodulin and ATP on the activity of ethylene forming enzyme obtained from tomatoes and green pea pods
✍ Njoroge, Charles K; Kerbel, Eduardo L; Briskin, Donald P 📂 Article 📅 1998 🏛 John Wiley and Sons 🌐 English ⚖ 242 KB 👁 1 views

Ethylene forming enzymes (EFE) from both peas and tomatoes were prepared. EFE from both sources were inhibited by adenosine triphosphate (ATP). Exogeneous calmodulin had no e †ect on EFE activity either in the presence or absence of ATP. The presence of gramicidin in pea microsomal membrane EFE did