Membrane protein structures, uncertainty

There may be abnormalities in eiythrocyte membrane transport properties in patients with bipolar affective disorders, though the interpretation is confounded by the uncertainty with regard to the contribution of hypertension in patients who are coincidentally hypertensive and manic depressive. The administration of lithium also may cause adaptive change (93,117,135-137). This results in an increase in erythrocyte lithium concentrations after prolonged lithium therapy, which could be mediated either by increased flux into the cell or via reduction in efflux rate. An increased content of ankyrins, red cell membrane proteins affecting cytoskeletal structure and functions, has been found in some patients with bipolar affective disorder (138) and this raises further the role of erythrocyte membrane defects in the etiology of the disease. 

It has been shown that the molecular weight of monomeric units of mitochondrial structural protein is not 22,500, as first reported by Griddle et al. (1962), but 64,000 (Lenaz et al., 1968). Thus monomeric molecular weights ranging from 10,000 to 40,000 such as reported, for example, for the red cell membrane structural protein (Bakerman and Wasemiller, 1967 Zahler, 1968) should be reassessed, not only in view of previously discussed uncertainties concerning the purity of isolated structural protein, but also because of possible errors (Lenaz et al., 1968) in the estimation of these molecular weights. 

---