Final answer:
The macula densa in mammalian nephrons helps regulate the release of renin, which in turn affects the production of angiotensin and hormones like aldosterone and ADH. These hormones play important roles in maintaining water and sodium balance in the kidneys.
Step-by-step explanation:
The macula densa is a group of cells in mammalian nephrons that sense changes in sodium ion concentration. Its main function is to regulate the release of renin, which acts on angiotensin to form angiotensin I and II. Angiotensin II then stimulates the release of aldosterone and ADH, which play important roles in water and sodium regulation in the kidneys.