We have developed an isolated perfused tumor model to study the metabolism of solid tumors by nuclear magnetic resonance spectroscopy. Morris hepatomas (7777) were implanted in the inguinal region of Buffalo rats, such that they developed an isolated blood supply. These tumors were perfused with a RBC perfusate, removed from the animal, and studied by 31P nuclear magnetic resonance spectroscopy...

Extracellular electrophysiological recordings from single olfactory bulb (OB) neurons in the channel catfish, Ictalurus punctatus, indicated that the OB is divided into different functional zones, each processing a specific class of biologically relevant odor. Different OB regions responded preferentially at slightly above threshold to either a mixture of 1) bile salts (10(-7) to 10(-5) M Na(+)...

The membrane adenosine triphosphatase (E.C. 3.6.1.3) from Escherichia coli has been solubilized with Triton X-100 and purified to near homogeneity. The purified enzyme has a sedimentation coefficient of 12.9S in a sucrose gradient, corresponding to a molecular weight of about 360,000. On electrophoresis in gels containing sodium dodecyl sulfate, it dissociates into subunits with apparent molecu...

We check the Vaisman condition of geometric quantization for R-matrix type Poisson pencil on a coadjoint orbit of a compact semisimple Lie group. It is shown that this condition isn't satisfied for hermitian symmetric spaces. We construct also some examples when Vaisman condition takes place.

A method for measuring internal nucleoside triphosphate pools of lactococci was optimized and validated. This method is based on extraction of (33)P-labeled nucleotides with formic acid and evaluation by two-dimensional chromatography with a phosphate buffer system for the first dimension and with an H(3)BO(3)-LiOH buffer for separation in the second dimension. We report here the sizes of the r...

To determine whether verapamil prevents depletion of adenine nucleotides during and after severe myocardial ischemia, dogs were subjected to 15 min occlusions of the left anterior descending coronary artery followed by 240 min of reperfusion. One hour before occlusion, dogs were randomly assigned to a treatment group (n = 10) to which an infusion of intravenous verapamil was given until the ons...

It is well established that myosin will catalyze the hydrolysis of inosine triphosphate’ (l-3) as well as ATP. Even catalysis of inorganic triphosphate hydrolysis has been observed (4, 5).2 It has been reported recently (7) that uridine triphosphate is rapidly hydrolyzed in the presence of crystalline myosin, and previously unpublished experiments3 showed that synthetically made UTP4 is rapidly...

Phosphoinositidase C activities sensitive to purine and pyrimidine nucleotides have been identified earlier in ampulla from Rana ridibunda semicircular canal. The aim of this study was to characterize the pharmacological properties of other P2 receptors borne by this structure. A microassay was developed to measure the binding of [35S]adenosine 5'- O-(2-thiodiphosphate) ([35S]ADPβS) to a few am...