There’s a lot of misinformation going around about depression, which is not helped by a lack of understanding of the many underlying causes of depression itself and the effects of medical remedies we use to treat it.
Portuguese researchers looked at the specific effects that antidepressant drugs had on rats and discovered that a particular type, called clozapine, led to the growth of new brain cells, and might be useful in the treatment of depression.
The research, published in Translational Psychiatry, focused on five groups of rats. One group was used as a control, while the other four were made to exhibit depressive-like symptoms through chronic stress.
Scientists subjected the rodents to distressing conditions like short-term food or water deprivation and afterward put them near unobtainable food and water resources. The researchers also messed with the rats' day/night cycle and subjected them to strobe lights. During the last three weeks of this vexing approach, the rats were treated with different drugs.
One group was Prozac, a known antidepressant, while the other two were given antipsychotic drugs used to also treat depression. One group was given haloperidol, a classic antipsychotic, while the other was given clozapine, an atypical antipsychotic. The last group was given saline solution as a control.
The effects of these drugs were measured by the assessment of pleasure and despair. Pleasure was measured by how much sugar water (a tasty treat) the rats were drinking and despair was tested by looking at how quickly the mice were swimming to safety when forced to swim. Depressed mice had less sugar and didn’t really care if they were going to drown.
The team found a few interesting discoveries. The rats on clozapine were the most similar to the control group, followed by the ones on Prozac. Next were actually the rats on the saline solution and finally the one on haloperidol. Haloperidol has a sedative effect, which might explain why the rats were less willing to swim and remained still in the water for longer.
An analysis of the rats' brains showed that stress had a detrimental impact on neurogenesis, the growth of new brain cells, and also shortend their lives. Stress also contributed to the formation of shorter neurons with fewer connections. Clozapine appeared to reverse these effects.
Researchers note in the paper that a large proportion of patients treated with currently available antidepressant drugs fail to get better. Hopefully, this study will provide some vital clues for future effective treatments.