The Scared Flow

While in the secondary school, my school hosted an inter-house sports competition which turned out awry towards the end. Scaling through the fence for safety, gunshots went up in the air to keep
everyone calm but this worsened the case as more students struggled to escape as they climbed the 8-foot fence. As the tension subsided, I was shocked to see that my friend had some urine stream dripping from her skirts and trickling down her legs. She couldn’t explain what happened but we had to find a way to resolve the mess before other students got to know…  Locally referred to as weeing, peeing, pissing and tinkling, urination which is medically called micturition or voiding is the act of releasing urine from the urinary bladder through the urethra to the urinary meatus.
Urine is formed when the kidneys filter about 120 to 150 quarts of blood – producing about 1 to 2 quarts of urine. The urine is carried to the urinary bladder through thin tubes known as ureters. The bladder which acts as a reservoir can hold up to 300-400ml of urine.
In healthy humans, the process of urination is under voluntary control while in infants, some elderly persons and those with neurobiological injury, urination may occur as an involuntary action. Urination occurs when the bladder muscles contract and the external urethral sphincter, bladder neck and pelvic floor muscles relax. The urine then passes through the urethra to the outside.  
Pelvic nerves in the bladder tell when it is time to urinate because they are the primary nerve supply of the bladder, containing both sensory and motor parasympathetic fibers. As the bladder first gets filled with urine, a feeling to urinate will arise. The sensation to urinate becomes stronger as the bladder continues to fill and reach its limit. At that point, the sensory fibers detect the extent of stretch in the bladder wall and send a message to the pontine micturition center of the brain that the bladder is full, this increases the urge to empty the bladder.
Urine is expelled when the motor fibers return the reflex signal and stimulate the bladder muscles to tighten, squeezing urine out of the bladder. At the same time, the brain signals the sphincter muscles to relax. As these muscles relax, urine exits the bladder through the urethra. When all the signals occur in the correct order, normal urination occurs.
The micturition reflex is an autonomic spinal cord reflex that initiates urination. However, the frontal cortex sends inhibitory signals to the pontine micturition center – this helps to keep the urine in the bladder until the time is set to release it. Without the activity of the frontal reflex, urine will just flow out anytime the bladder is full. Under stress, inhibitory signals from the frontal lobe can be overridden by the limbic system – brain areas that control the ‘fight or flight’ response. When stressed, electrical signals from the limbic system become so intense that the micturition centre finds it difficult to follow inhibitory signals from the frontal lobe thereby, releasing urine involuntarily.
So next time you get to face any challenging or terrifying situation, try to keep your head. Be relaxed. Keep calm lest you let off some urine drops before you know it.

By Ifeyinwa Ugo-Amadi

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