The image below contains all the info you need about the renal physiology as to what substances are absorbed/secreted allover the different segments of the renal tubules. Plus, you get to see the types of different diuretics working on each segment. Below the image there is all this in a text format.

Click on image to enlarge it. P.S. version 2

Proximal convoluted tubule (PCT)

Working diuretics: osmotic e.g. Mannitol

Reabsorption of:

• Sodium (67%)
• Chloride (40%)
• Potassium (all)
• Water (equiosmotic amount)
• HCO3 ions (85%)
• Glucose, AA (all)

Secretion of:

• Creatinine
• Uric acid
• Antibiotics
• Some diuretics

Henle Loop

Working diuretics: Loop e.g. Furosemide

Reabsorption of:

• Sodium Chloride (25%)
• Potassium [desc. limb only]
• Water (equiosmotic amount) [desc. limb only]
• Magnesium
• Calcium

Secretion of:

• No secretion occurs at this segment

Distal convoluted tubule (DCT)

Working diuretics: thiazides e.g. Chlorothiazide [proximal part] – osmotic e.g. Mannitol, Pottasium sparing e.g. Amiloride [distal part]

Reabsorption of:

• Sodium Chloride (proximal part 10% – distal part 2-5% “under the effect of Aldosterone“)
• Water (equiosmotic amount) [distal part only] “under the effect of Aldosterone“
• Calcium [proximal part only] “under the effect of parathyroid hormone”
• Ammonia [distal part only]

Secretion of: [distal part only]

• Potassium
• Hydrogen

Collecting duct and tubules (medullary part)

Working diuretics: osmotic e.g. Mannitol

Reabsorption of:

• Water “under the effect of Anti-diuretic hormone”

Secretion of:

• No secretion occurs at this segment