Microprocedure to determine the polymorphic forms of acid α1-glycoprotein in plasma : Application to depressive patients treated with amitriptyline

The polymorphic forms of α₁-acid glycoprotein have been determined by isoelectric focusing of small samples of whole plasma, without prior isolation of the protein. The results obtained by this technique confirm the microheterogeneity of this glycoprotein, which is not due to artefacts. Densitometric measurements of the polymorphic forms of this protein, which binds antidepressive drugs, have been performed in twelve depressive patients.