Which of the following does NOT increase as a result of sympathetic stimulation?

During sympathetic stimulation, several physiological changes occur in the body as part of the "fight or flight" response. The sympathetic nervous system activates various pathways that ultimately aim to prepare the body for increased physical activity.

When considering glomerular filtration rate (GFR), it is important to understand its relationship with sympathetic stimulation. Sympathetic activation primarily leads to vasoconstriction of renal blood vessels, which can decrease renal perfusion and therefore GFR. So, while other parameters increase due to sympathetic activation to ensure that the body can respond effectively to stressors, GFR does not follow this pattern and often decreases instead.

In contrast, blood volume may not directly increase due to sympathetic stimulation; however, sympathetic activity does enhance renal tubules' reabsorption of sodium and water, effectively influencing blood volume indirectly over time. Total peripheral resistance typically rises because of widespread vasoconstriction in non-essential vascular beds. Cardiac output increases as well due to heightened heart rate and stroke volume resulting from sympathetic stimulation.

Therefore, the glomerular filtration rate is the only parameter mentioned that does not increase in response to sympathetic stimulation, making it the correct answer to the question.