Nucleotides and organophosphates of cardiac, fast, and slow muscles of chick during development

Nucleotides like ATP, ADP, AMP and organophosphate, a compd. like creatine phosphate, creatine, and creatinine were estd. in the cardiac, slow anterior latissimus dorsi (ALD) and fast posterior latissimus dorsi (PLD) muscles of the prenatal chick. A decrease in the ATP level and an increase in the ADP​/ATP ratio was obsd. with the advance in development in all muscle types. The increase in ADP level with an increase in development was noted with a complementary increase in the activity of ATP creatine transphosphorylase in all types. A gradual increase in creatine phosphate and a decrease in free phosphate in all the muscle types was recorded. The utilization of ATP as indicated by phosphate potential was suggested to be existing during development by way of increased transphosphorylation. The heart and ALD muscles exhibited similar trends in ATP utilization up to the 16th day. The Ca2+ and Mg2+ activated myofibrillar activity exhibited a decrease with ref. to development. The studies on ocular shortening of glycerinated fibers revealed that the contractility of the fibers progressively increased with development. The ALD fibers are bound to Ca2+ more than that of PLD and heart. The sensitivity of Ca2+ to the fibers changes with development as the PLD fibers become more sensitive:heart fibers lose their sensitivity; and ALD fibers have a mixed nature with ref. to Ca2+ sensitivity

EPR and Optical Studies of Mo5+ Ions in Lithium Molybdoborate Glasses

Electron paramagnetic resonance (EPR) and optical absorption studies of Li2O–MoO3–B2O3 with varying concentrations of Li2O, MoO3 and B2O3 have been carried out at room temperature. Two series of glasses, one with constant MoO3 (CM) and another with constant borate (CB), have been investigated. Characteristic EPR spectra of Mo5+ have been observed centered around g ≅ 2.00, which are attributed to Mo5+ ion in an octahedral coordination sphere with an axial distortion. The spectra also show strong dependence on the concentration of Li2O and B2O3. Spin concentrations (N) and magnetic susceptibilities (χ) have been calculated. In the CM series, the N values decrease with increasing Li2O content up to 30 mol%, while in the CB series variation of N is found to increase initially up to 20 mol%, and with further increase in the Li2O content the N values tend to decrease. The variation of magnetic susceptibilities is almost similar to that observed with the variation of N. From the optical absorption spectra, an absorption edge (α) has been evaluated. In the CM series, the values of α show a blueshift. On the other hand, in the CB series a redshift is observed. The observed variations in spectral parameters are explained by considering the molybdoborate network. Addition of Li2O to the CM and CB series results in modification of [MoO6/2]0 → [MoOO5/2]− and [BO3/2]0 → [BO4/2]− → [BOO2/2]− groups, respectively, leading to creation of nonbridging oxygens. The optical basicity of the glasses has been evaluated in both the CM and the CB glasses. The optical basicity can be used to classify the covalent-to-ionic ratios of the glass, since an increasing optical basicity indicates decreasing covalency. It is observed that the covalency between Mo5+ ions and oxygen ligands increases in the CB series, whereas in the CM series the covalency between Mo5+ ions and oxygen ligands decreases

Acetylcholinesterase activity in the embryonic muscles of chick

Acetylcholinesterase activity in the exts. of fast (posterior latissimus dorsi; PLD)​, slow (anterior latissimus dorsi; ALD)​, and cardiac muscles of embryonic chick was estd. by the titrimetric method. The activity in the fast PLD gradually increased up to 16th day of development and gradually decreased afterwards. In the slow ALD there was an increase in activity up to 16th day, but later on the activity became steady. The heart maintained a steady level from the 8th day onwards. The decay of activity in PLD and maintenance of steady level in ALD after the 16th day and in heart from the 8th day of incubation are discussed with ref. to the establishment of muscle-​nerve interaction

Differentiation of lysozyme activity in the fast, slow and cardiac muscles of chick

Lysosomal activity did not vary in embryonic muscles, whereas adult posterior latissimus dorsi muscles (PLD) of the wing of White Leghorn chicks showed greater activity than adult anterior latissimus dorsi muscles (ALD)​. Cardiac muscle showed very low lysosomal activity, that of embryo as well as of adult exhibiting the same specific activity. These results suggested that lysosomal activity was initially the same in all 3 embryonic muscles but, as the skeletal muscles differentiated into the adult types, they synthesized more active lysozyme than the heart. Among the skeletal muscles, the PLD synthesized more active enzyme than the ALD. Since greater lysozyme activity implied a well-​organized lysosomal activity existing in the muscle, from the standpoint of pathophysiol. significance, it was suggested that the adult skeletal muscles had to synthesize more lysozyme for protection, whereas the embryonic muscles were well-​protected by the lysozyme of the egg albumin

Antagonistic effects of glutamine and histamine on in vitro lysozyme activity

Glutamine [56-​85-​9] activates and histamine [51-​45-​6] inhibits the activity of a crystalline lysozyme [9001-​63-​2] prepn. as well as natural secretions like tears and nasal mucus

Salivary amylase activity in a millipede

Salivary amylase of a millipede (Thyropygus nigrolabiatus) showed similar enzyme kinetics as compared to those of insects. The amylase had an optimum pH of 5.4 at 39° and a Km value of 0.02​% for starch. Glucose 1-​phosphate (0.1M) significantly inhibited the enzyme activity when starch or glycogen was used as the substrate

Metabolic differentiation of fast, slow, and cardiac muscles of chick during development

In vitro anaerobic glycogenolysis by fast, slow, and cardiac chicken muscle increased during prenatal development, whereas glycogen formation decreased in cardiac and slow muscles but increased in fast muscles. Changes in glycogenolysis rate were correlated with values for O consumption, P​/O ratio, and succinic dehydrogenase-​cytochrome c oxidase activity. Lactate dehydrogenase, hexokinase, and glycogen phosphorylase activities showed that fast muscles became more anaerobic while slow and cardiac muscles became more aerobic during development. The response of in vitro glycogen formation in insulin and epinephrine varied with muscle type and development stage