In my opinion kundalini awakenings are associated with a tumescence of the "blueprint" of the bodymind. Within this amplified morphogenic field the cells set about reorganizing themselves to convey the upsurge of consciousness or Spirit. During this period of increased spiritual field there is greater vibration, rhythm, correspondence and communication between atoms, cells and organs. This is tacitly undeniable to anyone going through a kundalini awakening. In fact it is this intensification of sensation and function coupled with the abrupt breakthrough into expanded states of awareness that is most disturbing about the experience of kundalini, for we are so used to living in the half-death of collective conditioning. This higher integration is concurrent with increased psychic, extrasensory abilities, such that as we integrate our internal organism, we delve more deeply into the collective interiors of the human race and the globe. Through the elevation of the personal we access the transpersonal and tune into the Global Brain.
A good word to describe this amplified of being during metamorphosis is superfluid. We can assume that cell membranes become more permeable, including the blood brain barrier. Polarities become more pronounced, increasing the ion exchange and current flow between them. The fields of the organs, plexuses, brain and the body must be greatly expanded and magnified. There must be increased nutrient and waste product exchange coupled with greatly increased enzymatic action and oxygen usage. ATP and glucose metabolism must be at an all time high, as on every level we become more "alive and awake."
The cavity within the center of the spinal column itself both makes and contains cerebrospinal fluid. The super-charged body and expanded heart-field must act like a cyclotron on the spine. The cerebrospinal fluid probably becomes supercharged with ions and laden with neuropeptides, during awakening, accumulating to crescendo point with the inner-conjunctions. At the height of the awakening I imagine that all the cerebrospinal fluid becomes Amrita, or nectar of the Gods as it is saturated with ions, endorphins, glutamate, NO and various neurotransmitters.
Along with circulation of this fluid up the spine and around the brain cavities, the increased permeability between the cerebrospinal fluid and the blood following histamine release, could allow the elixir to flow within the bloodstream as well. After it bathes the brain and spine CSF is reabsorbed into venus sinus blood via arachnoid villi projecting into the superior sagittal sinus.
The amrita in the blood then would hyper-relax the entire bodymind and thereby energy is conserved and accumulated for the inner-conjunction. Supplanting the normal laborious flow of energy through nervous tissue this "spark," reminiscent of lightning, zaps many volts through the organism. Like lightning the spark could comprise of wave pulses of energy between the positive and negative poles, but moving so fast as to be perceived as one ongoing current.
Changing the voltage across a neuron membrane can open channels that allow various kinds of ions (including calcium ions) to enter and leave the neuron. The membrane's conductivity to ions is voltage dependent. The movement of ions (which constitutes an electric current) cause further changes in the membrane and so on--thus perpetuating a superfluid, supercharged state. There are references in the texts, especially those on Tantric Kriya Yoga on the magnetizing and ionizing of the cerebrospinal fluid (CSF). This ionized fluid then awakens and transforms the brain and broadens the range of conscious and sensory prehension.
Apparently breathing itself ionizes the CSF. According to Ipsalu Tantric Kriya Yoga a technique called the Cobra Breath pulls magnetic energy into the spine, ionizing the spinal fluid and allowing the kundalini to rise, bathing the brain in magnetized fluid and transforming consciousness. Check out Tantrabliss.com for more information on this. Most breathing techniques will aid in elevating and integrating consciousness.
Besides changes in the cell receptors other changes in the cell membranes would fuel the conflagration of superfluidity. Changes in the physio-chemical and EMF environment of the cell, along with increased temperature, hydrostatic pressure and osmotic pressure would lead to changes in the lipid composition of the cell membrane. This change in the cell membrane would in turn contribute to an upsurge in the rate/activity of cellular energy generation and metabolism. Thus creating a feedback relationship that would maintain hyperactivation until the resources necessary to perpetuate this contagion are depleted.