Final answer:
In response to increased renal blood pressure, the myogenic mechanism induces smooth muscle contraction in the afferent arteriole to maintain a consistent glomerular filtration rate, working with the tubuloglomerular feedback for precise autoregulation.
Step-by-step explanation:
When renal blood pressure rises, the myogenic mechanism for autoregulation of the glomerular filtration rate (GFR) triggers a response in the afferent arteriole supplying the glomerulus. The smooth muscle cells within the arteriole wall get stretched due to the increased pressure and respond by contracting, which reduces the lumen diameter and helps to resist the increased pressure, thereby maintaining a relatively constant GFR despite changes in systemic blood pressure. This myogenic response works in concert with the tubuloglomerular feedback mechanism, which involves the juxtaglomerular apparatus (JGA) and macula densa cells, to finely tune the GFR through paracrine signaling with factors like adenosine and nitric oxide.