Changes in erythrocyte morphology induced by imipramine and chlorpromazine

Chlorpromazine (CPZ), a phenothiazine derivative, is a potent antipsychotic agent and imipramine (IP) is a widely used tricyclic antidepressant. The interaction between these molecules and erythrocyte membranes is of particular interest considering the role of these cells in the transport and release of these drugs at the central nervous system. In the present paper, we intend to study the effects of IP on erythrocyte membranes and to compare these effects with those of CPZ. Erythrocytes from adult Sprague-Dawley rats were incubated separately with different concentrations of IP or CPZ for lh at room temperature, fixed and stained by Giemsa. Changes in erythrocyte morphology were quantified by an image analysis system. The interaction of both drugs, CPZ and IP, with the erythrocyte membrane causes similar changes in cell shape. Increasing concentrations of both drugs induces the formation of stomatocytes, spherostomatocytes and spherocytes, because of an irreversible loss of area and volume, probably due to endovesiculation. Our results also show that the CPZ is more potent than IP.