How does atrial natriuretic peptide help regulate blood pressure? ANP causes the kidneys to excrete excess sodium and therefore helps to regulate blood pressure and blood volume. 13. (Page 4.) of the following intestinal hormones: CCK, Secretin, GIP, or Motilin, which is responsible for creating peristaltic waves along the length of the intestines? motilin 14. (Page 4.) Which hormone of the kidney stimulates blood cell formation? Erythropoietin