The effects of imipramine on the methylation of phosphatidylethanolamine (PE) in the cortical membranes of Wistar rats.

This study investigates the effect of imipramine (IMI) on the methylation of phosphatidylethanolamine (PE) in crude cortical membranes of rat brain in vitro and ex vivo. It was found that IMI enhanced the formation of phosphatidyl-N-monomethylethanolamine (PME) and phosphatidyl-N,N-dimethylethanolamine (PDE) and inhibited the formation of phosphatidylcholine (PC) in the cortical membranes of rats in vitro. The same effect i.

Effect of imipramine on the membrane anisotropy and on the phospholipid methylation in the central nervous system of the rat.

An ex-vivo and in-vitro study of the effects of imipramine on the membrane anisotropy and phospholipid methylation in the rat cortical membranes was carried out. A comparative study of the membrane fluidity in various brain regions indicated different basal anisotropy of the areas and different reaction of these membranes to imipramine. It was found that imipramine when given to rats chronically (14 x 10 mg kg-1, i.

Effect of some cationic amphiphilic drugs on phospholipid methylation in the central nervous system of rats.

Imipramine, desipramine, citalopram and chlorpromazine in concentrations which corresponded with their concentration in the central nervous system of rats after pharmacological doses, potentiated phospholipid methylation in the synaptic cortical membranes of naive rats in-vitro. Chronic administration of imipramine, desipramine or citalopram induced changes in the activity of phospholipid methyltransferases since none of these drugs stimulated phospholipid methylation in the synaptic cortical membranes of rats treated with these antidepressants for two weeks. In contrast, chronic treatment with chlorpromazine did not change the sensitivity of phospholipid methyltransferases to the stimulating effect of chlorpromazine, whereas addition of haloperidol to the synaptic cortical membranes of rats treated chronically with haloperidol led to a decrease of phospholipid methylation.

Regional distribution of imipramine, desipramine and specific [3H]desipramine binding sites in the rat brain after acute and chronic treatment with imipramine.

Regional distribution of imipramine, desipramine and specific [3H]desipramine binding sites in the rat brain after acute and chronic treatment of rats with imipramine has been investigated. Both substances were distributed unevenly within rat brain after single and prolonged administration of imipramine. This was partly connected with the regional cerebral blood flow, lipid content in the regions and lipophilicity of the substances investigated.

Species differences in hepatic microsomal drug-metabolizing enzymes.

The activity of some metabolizing enzymes was assessed in the liver microsomes of Acomys cahirinus, mice and rats. The enzymatic studies were followed by the determination of cerebral level of apomorphine (APO), imipramine (IMI) and its metabolite desipramine (DMI) of animals treated with a single dose of APO or IMI. It was found that the level of cytochrome P-450 and the activity of IMI demethylase and glucuronyltransferase in the liver microsomes of rats was significantly higher than those in the liver microsomes of Acomys and mice.