Host Defense Mechanisms

Urine, although not an antimicrobial itself, possesses characteristics that are less than ideal for bacterial growth. Some of these characteristics include low pH, significant urea concentration, and high osmolality. Also, bacteria in the bladder can stimulate an urge to urinate. Additionally, prostatic fluid secretions in men can inhibit bacterial growth while normal vaginal flora in women such as Lactobacillus spp. can secrete


lactic acid which can decrease the pH of the enviroment.

There are several other host factors that inhibit what are known as bacterial virulence factors. These virulence factors are mechanisms that bacteria utilize to cause infection and/or ensure their survival. The first is glycosaminoglycan, a compound produced by the body that coats the epithelial cells of the bladder. This compound essentially separates the bladder from the urine by forming a protective layer against

bacterial adhesion. A second compound known as TammHorsfall protein is secreted into the urine, and prevents E. coli from binding to receptors present on the surface of the bladder. Other factors implicated in contributing to host defense mechanisms against UTIs include immunoglobulins, specifically IgA.

Blood Pressure Health

Blood Pressure Health

Your heart pumps blood throughout your body using a network of tubing called arteries and capillaries which return the blood back to your heart via your veins. Blood pressure is the force of the blood pushing against the walls of your arteries as your heart beats.Learn more...

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