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C Y KAO

Publications and source records attributed to C Y KAO.

At least 19 recordsLinked to original sources
PubMed1964

IDENTITY OF TARICHATOXIN AND TETRODOTOXIN.

Tarichatoxin (C(11)H(17)N(3)O(8)), a potent neurotoxin recently isolated in pure form from the eggs of the California newt, Taricha torosa, has been found to be identical to tetrodotoxin from the ovaries of Sphoeroides rubripes, the Japanese Fugu or puffer fish. As yet this substance has been detected only in a single family of fish, Tetraodontidae, and in a single family of amphibia, Salamandridae.

Amphibians↗
PubMed1956

Changing electrical constants of the Fundulus egg plasma membrane.

Electrical constants of the plasma membrane of the Fundulus egg have been measured with microelectrodes by the transient method. No consistent and significant membrane potential was measured. Membrane capacity averages 0.63 microF/cm.(2) for both unactivated and activated eggs. Membrane resistance averages 3450 ohm-cm.(2) in the unactivated eggs, but increases 2 to 7 times to an average of 13,290 ohm-cm.(2) in the fully activated state. In a hypertonic sucrose solution, the swelling of the egg proper is accompanied by a rapid fall of membrane resistance towards that in the unactivated state. The changes of the membrane resistance are interpreted as probably caused by alterations in the effective pore size in the plasma membrane.

Animals↗
PubMed1956

Pressure-volume relationship of the Fundulus egg in sea water and in sucrose.

Upon activation, an internal hydrostatic pressure develops within the Fundulus egg, and compresses the egg proper to a reduced volume. When the perivitelline pressure is abolished by a highly hypertonic sucrose solution, the egg volume increases. As sucrose penetrates the chorion, the volume again decreases. The relation between P and V in these conditions is inverse, and approximates a rectangular hyperbola. The limiting factor causing most of the deviation is shown to be the incompressible fraction. It is concluded that the volume of the egg proper is controlled by the perivitelline pressure, and that the effect of hypertonic sucrose solution is exerted by lowering the pressure and thereby increasing membrane permeability non-specifically. It is also shown that some permanent alterations occur within the plasma membrane during activation that reduce the permeance, and thereby, increase the incompressible fraction.

Animals↗