Quantification of p38jsynaptophysin in highly purified adrenal meduUary chromaffin vesicles
نویسندگان
چکیده
Chromaffin vesieles were first purified by differential and density gradient centrifugation in isotonie (Percoll) gradients. In subsequent suerose gradients p38jsynaptophysin exhibited the same distribution as established marker substances of chromaffin vesieles. Quantification of immunoblots revealed that 750 ng p38{synaptophysin per mg of protein were present in the chromaffin vesieles reeovered from the sucrose gradient. Thus the amount of p38jsynaptophysin per mg protein of chromaffin vesieles is about 100 times lower than that observed in elear (synaptic) vesieles. However. because of the !arge ditference in surface area and pro tein contenl, the amounl of p38jsynaptophysin per single vesicle is the same in both types of organelles.
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