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G A Vergara

Publications and source records attributed to G A Vergara.

4 recordsLinked to original sources
PubMed1981

Halothane modifies colchicine binding to tubulin.

Tubulin extracted from rat brains was incubated at 37 degrees C with 3H-colchicine in the presence and absence of 28 mM halothane. The amount of 3H-colchicine bound to tubulin was reduced by nearly 50% at a colchicine concentration of 5 x 10(-5) M when halothane was present. At low (1 x 10(-7) M) and at high (1 x 10(-3) M) concentrations of colchicine, halothane did not affect the binding as much. The inhibition of colchicine-binding to tubulin by halothane appeared to be non-competitive.

Animals↗
PubMed1979

Effects of halothane on microtubules in the sciatic nerve of the rat.

The effect of halothane and colchicine on microtubule repolymerisation after exposure to cold has been examined in the sciatic nerve of the rat. Myelinated axons showed a significant decrease in microtubule numbers and density after exposure to both 20 mM halothane and 10(-5) M colchicine; exposure to both agents simultaneously produced a further significant reduction when compared to halothane alone. It is suggested that halothane can interfere with microtubule repolymerisation in mammalian axons possibly in a similar way to that described in invertebrates.

Animals↗
PubMed1978

Static pressure-volume curves for the lung of the frog (Rana pipiens).

1. Static pressure/volume curves have been determined for isolated frog lungs inflated with either air or saline. In both cases a hysteresis was present: the pressure required to produce unit change of volume being greater during inflation than deflation 2. The pressure necessary for a given volume change was less for the saline-filled than the air-filled lungs. The difference between these curves is due to the surface tension at the air/lung interface. 3. Pressure/volume curves for air-filled lungs in situ were similar to curves for isolated lungs. However, a greater pressure was required for the same volume change during both inflation and deflation. 4. Compliance was calculated from different parts of air pressure/volume curves and gave values greater than those obtained using similar calculations for higher vertebrates. 5. These observations support other evidence for the presence of a surfactant in the lung lining of frogs in spite of the relatively large diameter of their 'alveoli.' The precise role of such a lining is uncertain and it is concluded that similar forces may be involved during the inflation and deflation of lungs of frogs and higher vertebrates in spite of differences in gross morphology.

Animals↗