The water-soluble proteins of bovine skeletal muscle

1960 ◽  
Vol 86 (2) ◽  
pp. 238-250 ◽  
Author(s):  
M.J. Kronman ◽  
L.E. Weinberger ◽  
R.J. Winterbottom
Keyword(s):  
Skeletal Muscle ◽  
Soluble Proteins ◽  
Water Soluble ◽  
Bovine Skeletal Muscle

HYDROLYTIC ENZYMES IN BOVINE SKELETAL MUSCLE: I. STARCH GEL ELEGTROPHORETIC SEPARATION AND PROPERTIES OF SOLUBLE ESTERASES

1965 ◽  
Vol 43 (11) ◽  
pp. 1779-1786 ◽  
Author(s):  
H. F. MacRae ◽  
C. J. Randall
Keyword(s):  
Skeletal Muscle ◽  
Skeletal Muscles ◽  
Hydrolytic Enzymes ◽  
Water Soluble ◽  
Heat Stable ◽  
Heat Labile ◽  
Zone Electrophoresis ◽  
Starch Gel ◽  
Bovine Skeletal Muscle ◽  
Naphthyl Acetate

Water-soluble esterases of certain bovine skeletal muscles were separated by horizontal zone electrophoresis in starch gel in a discontinuous ouffer system. Eighteen bands of esterase activity were detected by the use of α-naphthyl acetate and α-naphthyl butyrate as substrates. Other substrates and various inhibitors were used to characterize the separated enzymes. A group of presumed isozymic esterases (three bands), which hydrolyzed α-naphthyl butyrate but not any other substrate tested, was sensitive to organophosphates, was heat labile, and was classified as aliesterase or, more specifically, as butyrylesterase. Another group of presumed isozymic esterases (four bands) hydrolyzed only α-naphthyl acetate and indoxyl acetates, was heat stable and resistant to organophosphates, and was tentatively classified as arylesterase or cathepsin. Eleven heat-labile esterase bands hydrolyzed both α-naphthyl acetate and α-naphthyl butyrate, were sensitive to organophosphates, and were classified as nonspecific aliesterases.

The cellular basis of corneal transparency: evidence for ‘corneal crystallins’

1999 ◽  
Vol 112 (5) ◽  
pp. 613-622 ◽  
Author(s):  
J.V. Jester ◽  
T. Moller-Pedersen ◽  
J. Huang ◽  
C.M. Sax ◽  
W.T. Kays ◽  
...  
Keyword(s):  
Cellular Level ◽  
Soluble Proteins ◽  
Water Soluble ◽  
Corneal Tissue ◽  
Corneal Epithelial Cells ◽  
Corneal Epithelial ◽  
Corneal Transparency ◽  
Scattering Measurements ◽  
Class 1

In vivo corneal light scattering measurements using a novel confocal microscope demonstrated greatly increased backscatter from corneal stromal fibrocytes (keratocytes) in opaque compared to transparent corneal tissue in both humans and rabbits. Additionally, two water-soluble proteins, transketolase (TKT) and aldehyde dehydrogenase class 1 (ALDH1), isolated from rabbit keratocytes showed unexpectedly abundant expression (approximately 30% of the soluble protein) in transparent corneas and markedly reduced levels in opaque scleral fibroblasts or keratocytes from hazy, freeze injured regions of the cornea. Together these data suggest that the relatively high expressions of TKT and ALDH1 contribute to corneal transparency in the rabbit at the cellular level, reminiscent of enzyme-crystallins in the lens. We also note that ALDH1 accumulates in the rabbit corneal epithelial cells, rather than ALDH3 as seen in other mammals, consistent with the taxon-specificity observed among lens enzyme-crystallins. Our results suggest that corneal cells, like lens cells, may preferentially express water-soluble proteins, often enzymes, for controlling their optical properties.

The effect of a benzodiazepine, flurazepam, on the response of in vitro skeletal muscle preparations to muscle relaxants: are purines or their receptors involved?

1982 ◽  
Vol 60 (7) ◽  
pp. 877-884 ◽  
Author(s):  
John T. Hamilton ◽  
Peggy A. Stone
Keyword(s):  
Skeletal Muscle ◽  
Phrenic Nerve ◽  
Neuromuscular Blocking ◽  
Muscle Relaxants ◽  
Water Soluble ◽  
Neuromuscular Activity ◽  
Changing Trends ◽  
Low Concentrations ◽  
Partial Blockade

Changing trends in the use of anxiolytic agents and recent reassessment of their neuropharmacological activity has prompted this evaluation of the peripheral neuromuscular activity of the benzodiazepine, flurazepam. In previous reports we have documented peripheral neuromuscular activity of chlordiazepoxide and diazepam on the rat phrenic nerve diaphragm preparation. The water soluble benzodiazepine, flurazepam, has been studied on the rat phrenic nerve diaphragm and frog rectus abdominis in vitro. On the former preparation flurazepam enhanced and then blocked the response to indirect electrical stimulation (0.2 Hz) and readily blocked posttetanic potentiation and prevented the preparation from sustaining a tetanic contracture (30 Hz). On the later preparation, flurazepam blocked in a noncompetitive manner the response of the frog muscle to applied cholinergic agonists. Studies on the rat preparation with the neuromuscular blocking drug succinylcholine have shown an unexpected protection against blockade in preparations pretreated with low concentrations of flurazepam. This was not observed when flurazepam was given prior to d-tubocurarinc. The application of adenosine to rat diaphragms during steady-state partial blockade caused by flurazepam or d-tubocurarine showed an inhibiting action of adenosine which was reversed by theophylline. Pretreatment of rat preparations with dipyridamole significantly enhanced the blocking action of standard concentrations of succinylcholine.These results, along with those in the literature, encourage a reassessment of the action of purines and benzodiazepines on skeletal muscle and encourage a consideration of a possible involvement of purinergic neuromodulation of transmission which is unmasked when the safety factor for transmission is altered by muscle relaxants. The possible clinical significance of protection against succinylcholine by benzodiazepines is noted.

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