Subunits of Sodium Channels
نویسندگان
چکیده
The purified Na+ channel from rat brain consists of a (260 kDa), Bl (36 kDa), and ,192 (33 kDa) subunits. Pure ,t?l subunits were prepared from purified rat brain Na+ channels which had been adsorbed to hydroxylapatite resin and used to prepare specific anti-81 subunit antiserum. Antibodies purified from this antiserum by antigen affinity chromatography immunoprecipitate 12SI-labeled, purified @l subunits and purified Na+ channels (measured as high affinity r3H] saxitoxin binding sites) and recognize /?l subunits on immunoblots of solubilized rat brain membranes. The affinity-purified anti-81 antibodies recognize @l subunits in rat spinal cord, heart, skeletal muscle, and sciatic nerve, but do not detect immunoreactive Bl subunits in eel electroplax or eel brain. The developmental time course of expression of immunoreactive 81 subunits in rat forebrain was measured by immunoprecipitation followed by immunoblotting with affinity-purified anti-81 antibodies. The amount of immunoreactive fll subunits increased steadily to adult levels during the first 21 days of postnatal development.
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