Thyroid hormones are essential for development and function of the brain because they are involved in neuron formation and migration, formation of axons and dendrites, myelinization
, development of synapses, and regulation of specific neurotransmitters in the fetal and postnatal periods (4).
During adolescence, brain neurogenesis and synaptogenesis activity are similar to adulthood and, concurrently, myelinization
The extent of myelinization
affects the size of ONH.
In addition, it is necessary for the improved function of the immune system, cellular breath, bone formation, normal cardiac function, conjunctive tissue development, myelinization
of spinal marrow, keratinization and pigmentation of tissues.
In the brain, pregnenolone is found naturally in high concentrations, and is considered neuroprotective, due to its ability to reduce neuronal death, and enhance myelinization
, (7) as demonstrated in brain cultures.
Specific neurosteroids modulate function of several receptors, and also regulate growth of neurons, myelinization
and synaptogenesis in the central nervous system.
Brain magnetic resonance showed disruption of the myelinization
of the white matter.
Effects of prenatal exposure on neuronal migration, neurogenesis and brain myelinization
in the mice brain.
Tancredi also briefly describes two other processes of abiding interest to the neurobiologist, namely, selective myelinization
and dendritic sprouting, both anatomical indicators of primary or recuperative learning.
They may perturb commitment of neural stem cells, proliferation of neuronal progenitor cells, cell migration, synaptogenesis, cell death, formation of transmitters and receptors, trimming of connections, myelinization
, and development of the blood-brain barrier (BBB).
Local anaesthetics reversibly block nerve conduction and nerve susceptibility depends on both the nerve fibre characteristics, namely diameter and myelinization
, and the physico-chemical properties of the drug.