In isolated rat hearts which can or cannot utilize fatty acids (FA) as substrates the coronary responses to an increase in flow were studied under three different conditions: a) control, during perfusion with glucose-enriched Tyrode solution which allowed the hearts to utilize long-chain FA from the endogenous pool, b) during forced utilization of glucose obtained with oxfenicine, an inhibitor ...

Buglia (1) had observed that absence of calcium suppresses the rythmic contractions of intestine. Vanysek (2) stated that calcium chloride stimulates the circular and relaxes the longitudinal muscle in the excised intestine of the cat. Robertson (3) reported that deficiency of calcium produces hypertonicity of the colon. Later Jhonson (4) found that cooling and reduction of calcium ion reduced ...

hemagglutination activity (enhanced lectin activity) not expressed by nonactivated platelets, and this agglutinin mediates the direct platelet-platelet interactions that cause the aggregation of thrombinactivated platelets. The enhanced agglutinin activity of thrombin-activated platelets is composed of two components: a plasma membrane-bound component and a soluble component.3 The expression of...

The effects of variation in calcium concentration on the action potential of Purkinje fibers isolated from the dog heart were studied. Action potentials recorded during perfusion with Tyrode solution containing 2.7 mM calcium chloride were compared with those recorded during subsequent perfusion with solutions containing 0.675 ( l / 4 x ) , 1.35 ( l / 2 x ) , 5.4 (2x) , or 10.8 (4x) mM calcium ...

The relationship between lymph flow and intestinal secretion was studied in an isolated, vascularly perfused cat ileal preparation in which secretion was caused by three different means: 1) plasma dilution from a constant infusion of Tyrode solution (2.5 ml/min per kg), 2) elevation of intestinal venous pressure to 30 mmHg, and 3) exposure to cholera toxin. In the plasma-dilution group, lymph f...

Kohzuki, Hisaharu, Hiromi Misawa, Susumu Sakata, Yoshimi Ohga, Hiroyuki Suga, and Miyako Takaki. Energy expenditure by Ba21 contracture in rat ventricular slices derives from cross-bridge cycling. Am. J. Physiol. 276 (Heart Circ. Physiol. 45): H74–H79, 1999.—To clarify the energy-expenditure mechanism during Ba21 contracture of mechanically unloaded rat left ventricular (LV) slices, we measured...

The aim of this study was to investigate the effect of aerial parts of Stachys lavandulifolia Vahl. Extract on the rat ileum contractions. The crude extract was prepared by maceration method (90% methanol) followed by fractionating into chloroform, ethyl acetate, petroleum ether and water. In adult male Wistar rats, ileum was sectioned and mounted in tissue bath and their contractility was reco...

The detachment forces of various polymers are frequently measured to determine their mucoadhesion strength. As the process of mucoadhesion is a consequence of interactions between the mucus layer on mucosa and mucoadhesive polymers, it is greatly dependent on mucus and polymer structure including their charge. It is also known that the glycosaminoglycan layer, which covers the urinary bladder m...

Rabbit isolated hearts were perfused according to Langendorff with Tyrode solution. Prostaglandin-like substances (PLS) in the effluent were purified and assayed on the rat stomach strip Noradrenaline (NA) in the effluent was assayed fluorimetrically. 2 Infusion of nicotine (1 muM-50 muM) caused a dose-dependent, brief increase, from 1.2+/-0.4 to maximally 8.3+/-2.1 ng/min, in the outflow of PL...

This study aims to evaluate whether endogenous ATP or adenosine modulates the neurotransmission and contractile function of mouse phrenic nerve-diaphragm. Bath application of ATP (1 mM) and alpha, beta-methylene ATP (m-ATP, 0.1 mM) elevated muscle tones, depressed contractions (approximately 12%), and depolarized muscle membranes (approximately 20 mV). Adenosine (1 mM) or low concentrations of ...