Posts Tagged ‘hormones’

Cortisol – NREM / Testosterone – REM , hormones and sleep

October 6, 2012

This is for those interested in new ideas in science.  For many years I’ve been looking at sleep, the Enteric Nervous System and other related fields. This post is somewhat advanced but most will find it fascinating and easy to follow.

For more of my biological ideas see the links below. My health hypothesis (that asks such things as: is there a bio basis to unconscious trauma?  why do we sleep?  what is the importance of the division of the body processes into catabolic and anabolic, etc.) is going through many changes, and the info here may be out of date, or changed or adjusted. – Tom Hendricks

CORTISOL, TWO DISEASES, WEIGHT PROBLEMS  Cortisol, how two diseases may connect weight problems to infant trauma  (posted 7/13)

BIOLOGY HYPOTHESIS  Hendricks Health Theory – the latest news [This link is the biggest summary and the most up to date post]

Please also see this update on cortisol, our wake up clock – how it’s set up an alarm clock inside each of us from 6-8AM. Also see the comments to this post for more up to date info.  Cortisol, wake up clock


Cortisol-NREM/ Testosterone-REM hormones and sleep.

There may be a hormonal component to sleep that gives us clues to why we need sleep.

Here are some clues that are interesting. They involve Cortisol and its relationship to NREM or slow wave sleep, and Testosterone and its relationship to REM sleep.
I suggest that perhaps the cortisol/testosterone ratio is a key component of sleep and health.

Cortisol, the stress hormone, is mostly released in sleep. Sleep = alternating long periods of NREM sleep with short periods of REM sleep.

Cortisol, seems to be released in NREM sleep. More cortisol = more NREM sleep.

Testosterone, the male hormone, is mostly released in REM sleep.

‘The cortisol / testosterone ratio’ seems to be important and is much studied.

Cortisol increases glucose/protein/fat metabolism – so sleep would be increased glucose/protein fat metabolism for the body.

Cortisol reduces inflammation and stress – so sleep would be important for immunity.

Cortisol stimulates growth hormone (GH) – so sleep would stimulate growth.

Too much cortisol – cushing’s disease OBESITY, HIGH BLOOD PRESSURE, DIABETES. Compare with


That suggests this possibility – too much cortisol/ too little testosterone = obesity. too little cortisol and too much testosterone = weight loss, eating disorders.

Just about all the cells in the body have receptors for cortisol, and will take it up. So cortisol helps just about every cell in the body – more in sleep and NREM, when it is at it’s highest. It is strong help for stress – would help restore body, get rid of fear, etc. etc. Yet another benefit of sleep

There are two main adrenal hormones, adrenaline, and cortisol. Seems loosely that adrenaline is fight or flight – a big response for emergencies, and cortisol, is stress resolved during sleep -a small response or cortisol is adrenaline lite. And works for immunity in sleep as well as it’s other functions.

There is a circadian rhythm in the liver – bile production stops in the evening, and the liver switches over to synthesizing chemicals and processing accumulated toxins.

The ENS or gut brain produces slow muscle contractions followed by short periods of rapid muscle movements, that correspond to the cycles of deep sleep and REM. AND
Most brain areas show greatly increased blood flow during REM sleep. This suggest that the body prepares cortisol during NREM, and then sends it out during the REM increased blood flow phase.

Discussion – I would suggest that the reason we sleep is to nurture the body and brain during it’s nightly rest period, and that it’s a two step process that involves cortisol being pumped throughout the body during the short REM phases, and cortisol doing its hormonal work during the longer NREM phases. And the first phase of sleep being the production of Cortisol. And that there is a ratio of hormones – cortisol and testosterone that must be in balance. And that too much cortisol to testosterone suggests stress response, and too little cortisol to testosterone suggests a too violent response.

Facts/ Quotes/ Studies

” Lack of sleep disrupts every physiologic function in the body,” said Eve Van Cauter of the University of Chicago. “We have nothing in our biology that allows us to adapt to this behavior.”

Cortisol levels start to rise approximately 2–3 hours after sleep onset and continue to rise into the early morning and early waking hours. The peak in cortisol is about 9 a.m.; as the day continues, levels decline gradually.

Acute administration of cortisol increases non-rapid-eye movement (non-REM) sleep, suppresses rapid-eye movement (REM) sleep and stimulates growth hormone (GH) release in healthy subjects.

Testosterone is produced in bursts that seem to coincide with the phase of sleep that comes just before Rapid-Eye Movement (REM) sleep. REM sleep itself comes in bursts, which usually last longer as the night progresses. Testosterone levels gradually build up over the course of the night, which is why testosterone levels are highest in the morning and lowest in the evening.

REM-sleep is needed for lasting forgetting of fear.

We found that evolutionary increases in mammalian sleep durations are strongly associated with an enhancement of immune defences as measured by the number of immune cells circulating in peripheral blood. This appeared to be a generalized relationship that could be independently detected in 4 of the 5 immune cell types and in both of the main sleep phases. Importantly, no comparable relationships occur in related physiological systems that do not serve an immune function. Consistent with an influence of sleep on immune investment, mammalian species that sleep for longer periods also had substantially reduced levels of parasitic infection.
These relationships suggest that parasite resistance has played an important role in the evolution of mammalian sleep.

In blood samples taken from patients before and after meals, the investigators discovered that bile acid recycling in the liver is disrupted without cortisol in humans, too.

After 9pm, the liver switches to its other primary functions, synthesizing chemicals and processing accumulated toxins.
The cycle begins shifting around 3am, when the liver slows chemical synthesis and readies itself for bile production.
The liver cycle shifts again around 3pm, when chemical synthesis begins to increase and bile production decreases.
Thus, the liver is most prepared to aid digestion with its synthesis of bile between 9am and 9pm.

It now turns out that another normal function of cortisol is to help prepare your body to digest food. When you get hungry, your body starts to make cortisol. This cortisol communicates to your liver, telling your liver to fill up your gall bladder with bile so that you can digest the fats that will be in the upcoming meal. When you eat, the bile is released into your small intestine to perform vital roles in digestion.

During tonic REM sleep, most brain areas show greatly increased blood flow, almost uniformly greater than 50% above the waking level, and as great as nearly 200%. During phasic REM sleep, there are transient further increases in blood flow to most brain regions, although precise quantification is difficult because the phasic episodes are so short.

During sleep the brain in the gut produces ninety minutes of slow muscle contractions followed by short periods of rapid muscle movements, cycles that correspond to the cycles of deep sleep and REM. When the brain is in deep sleep, the gut quiets down (there is ‘decreased small intestinal motility”), whereas REM has “immediate stimulatory effects on colonic motility” like those that occur with arousals and waking.

Increased testosterone-to-cortisol ratio in psychopathy. (study)

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