Final answer:
In glomerular diseases that remove the negative charges on the glomerular barrier, proteins would not be repelled, leading to an increased leakage of proteins into the urine, a condition known as proteinuria, and possibly cascading into nephrotic syndrome with symptoms like swelling and low serum albumin.
Step-by-step explanation:
If the negative charges on the glomerular barrier are removed, proteins, particularly negatively charged proteins, would no longer be repelled and could pass through the glomerulus into the urine. The negative charges of the proteins associated with the fenestrations of the glomerular capillary walls play a crucial role in preventing negatively charged substances like albumin from passing into the urine. This mechanism helps maintain the selectivity of the glomerular filtration barrier, allowing the kidneys to retain essential proteins while filtering out wastes.
In the event of a disease causing the removal of these negative charges, such as in some glomerular diseases, there could be a higher permeability of the barrier to proteins. This loss of selectivity can lead to proteinuria, where proteins like albumin are found in the urine, contributing to conditions such as the nephrotic syndrome. In nephrotic syndrome, the excess loss of proteins into the urine can lead to symptoms such as swelling, low serum albumin, and high cholesterol.
Normally, substances with a size less than 4 nm pass readily, and most substances up to 8 nm in size can cross the filtration barrier. The charge plays a pivotal role too; negatively charged proteins in the barrier help to repel negatively charged substances. This selective process results in a filtrate that is free of cells and large proteins. If negatively charged proteins are lost, this could disrupt the balance, leading to an increased passage of substances normally excluded, causing a range of pathological conditions linked to defective filtration.