Nimodipine effects on cerebral microvessels and sciatic nerve in aging rats

Area of Science:

• Neuroscience
• Gerontology
• Pharmacology

Background:

• Aging leads to cerebral microvascular anomalies, including perivascular deposits and pericyte degeneration.
• Previous studies showed nimodipine reduced these deposits when initiated later in life (24-30 months).
• The efficacy varied across cortical layers, prompting investigation into earlier intervention.

Purpose of the Study:

• To investigate the effect of earlier onset nimodipine treatment (16-30 months) on age-related cerebral microvascular changes.
• To assess the impact of early nimodipine treatment on pericyte degeneration.
• To evaluate the effect of long-term nimodipine treatment on sciatic nerve myelinated fiber morphometry in aged rats.

Main Methods:

• Ultrastructural analysis of cerebral microvasculature and sciatic nerves in aged rats.
• Chronic administration of nimodipine at different onset ages (24-30 months vs. 16-30 months).
• Morphometric analysis of myelinated fibers and myelin irregularities.

Main Results:

• Earlier nimodipine treatment (16-30 months) consistently reduced microvascular deposits across all cortical layers.
• Nimodipine did not affect the rate of pericyte degeneration in the brain.
• Nimodipine treatment showed a moderate reduction in myelin ballooning in sciatic nerves but did not significantly alter other age-related morphometric changes.

Conclusions:

• Early and sustained nimodipine treatment effectively mitigates age-related microvascular pathology in the brain.
• Nimodipine demonstrates a more pronounced effect on cerebral microvessels than on peripheral nerve myelinated fibers during aging.
• These findings highlight the potential of early pharmacological intervention to address cerebrovascular aging.