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What is All are true about macula densa except and explain in detail?
This mechanism involves a feedback loop in which the concentration of NaCl in the tubular fluid is sensed by the macula densa of the juxtaglomerular apparatus and conveed into a signal or signals that affect afferent aeriolar resistance and thus the GFR. When the GFR increases and causes in the tubular fluid at the macula densa to rise, more NaCl enters the macula densa cells. This leads to an increase in the formation and release of ATP and adenosine, a metabolite of ATP, by macula densa cells, which causes vasoconstriction of the afferent aeriole. Vasoconstriction of the afferent aeriole returns the GFR to normal levels.