Ontogenetic development of peripheral benzodiazepine binding sites in rat brain, heart and lung.

In rats, the brain exhibits negligible ontogenetic changes, while a steady marked increase in the density of peripheral benzodiazepine binding sites (PBS) has been demonstrated in the heart and lungs, reaching maximal levels at 31 days after birth. It may be that PBS play a role in the cellular proliferation of these peripheral organs. The present findings are consistent with current evidence of a relationship between these binding sites and mitochondrial function.