Innervation of the bladder

1. What is the role of the frontal lobe in voiding? The pontine micturition center?
2. What nerves are responsible for allowing contraction of the bladder and emptying?
3. What nerves are responsible for urine storage?
4. What nerve is responsible for prevention of urine leakage and emptying?
5. Where are M2 cholinergic muscarinic receptors located? Where are beta-2 adrenergic receptors concentrated? Alpha-adrenergic receptors?

Answers:
1. The corticopontine mesencephalic nuclei of the frontal lobe inhibits the parasympathetic sacral micturition center, allowing for bladder storage. The pons coordinates bladder contraction and sphincter opening.
2. The parasympathetic efferents S2-4, traveling through the pelvic nerve.
3. The sympathetic efferents T11-L2, traveling through the hypogastric plexi.
4. The pudendal nerve, containing somatic efferents S2-S4.
5. M2 receptors are located in the bladder wall, trigone, bladder neck, and urethra. Beta-2 receptors are in the body of the bladder and neck. Alpha-adrenergic receptors are in the base of the bladder (neck and proximal urethra).