Metabolic acid-base disorders occur when there are primary changes in the concentration of bicarbonate (HCO3 −) in the extracellular fluid (ECF). This can result from the addition of acid or the loss of alkali from the body. In response to metabolic acidosis, pulmonary ventilation increases, leading to a decrease in PCO2. The pulmonary response to metabolic acid-base disorders happens quickly, within minutes. The renal response, on the other hand, takes several days and involves an increase in renal net acid excretion (RNAE). Conversely, an increase in ECF [HCO3 −] causes alkalosis. This leads to a rapid decrease in pulmonary ventilation within minutes to hours, which in turn elevates PCO2 as a compensatory response. The decrease in RNAE also takes several days.

Respiratory acid-base disorders occur due to primary changes in the partial pressure of carbon dioxide (PCO2). An elevation of PCO2 results in acidosis, and the kidneys respond by increasing RNAE. Conversely, a reduction in PCO2 leads to alkalosis, and RNAE is decreased. The renal response to respiratory acid-base disorders occurs over several hours to days.

The regulation of liminal acidification in the kidney is controlled by the V-ATPase, and acid-base sensing in the kidney involves molecular mechanisms. Proximal tubule function and response to acidosis play important roles in acid-base homeostasis. Acid-base disorders are also integrated with electrolyte disorders.

Ammonia transport in the kidney is facilitated by rhesus glycoproteins. The endocrine system plays a role in regulating energy metabolism, calcium and phosphate metabolism, and the hypothalamus and pituitary gland. The thyroid gland, adrenal gland, and male and female reproductive systems are also part of the endocrine and reproductive systems.
Hamm LL, et al. Cellular mechanisms of renal tubule acidification. In: Alpern RJ, et al., eds. Seldin and Giebisch’s The Kidney: Physiology and Pathophysiology. 5th ed. Waltham, MA: Elsevier; 2013.
Weiner ID, Verlander JW. Renal acidification mechanisms. In: Taal MW, et al., eds. Brenner and Rector’s The Kidney. 9th ed. Philadelphia: Saunders; 2012.
Berend K, et al. Physiological approach to assessment of acid-base disturbances. N Engl J Med. 2014;371:1434-1445.
3.
Metabolic acid-base disorders result from primary alterations in ECF [HCO3 −], which in turn results from addition of acid to or loss of alkali from the body. In response to metabolic acidosis, pulmonary ventilation is increased, which decreases PCO2. The pulmonary response to metabolic acid-base disorders occurs in a matter of minutes. RNAE is also increased, but this takes several days. An increase in ECF [HCO3 −] causes alkalosis. This rapidly (minutes to hours) decreases pulmonary ventilation, which elevates PCO2 as a compensatory response. RNAE is also decreased, but this takes several days.
4.
Respiratory acid-base disorders result from primary alterations in PCO2. Elevation of PCO2 produces acidosis, and the kidneys respond with an increase in RNAE. Conversely, a reduction of PCO2 produces alkalosis, and RNAE is reduced. The kidneys respond to respiratory acid-base disorders over several hours to days.
Breton S, Brown D. Regulation of liminal acidification by the V-ATPase. Physiology (Bethesda). 2013;28:318-329.
Brown D, Wagner CA. Molecular mechanisms of acid-base sensing in the kidney. J Am Soc Nephrol. 2012;23:774-780.
Curthoys NP, Moe OW. Proximal tubule function and response to acidosis. Clin J Am Soc Nephrol. 2014;9:1627-1638.
Hamm LL, et al. Acid-base homeostasis. Clin J Am Soc Nephrol. 2015;10:2232-2242.
Levin LR, Buck J. Physiological roles of acid-base sensors. Annu Rev Physiol. 2015;77:347-362.
Roy A, et al. Collecting duct intercalated cell function and regulation. Clin J Am Soc Nephrol. 2015;10:305-324.
Seifter JL. Integration of acid-base and electrolyte disorders. N Engl J Med. 2014;371:1821-1831.
Weiner ID, Verlander JW. Ammonia transport in the kidney by rhesus glycoproteins. Am J Physiol Renal Physiol. 2014;306:F1107-F1120.
SECTION 8The Endocrine and Reproductive Systems BRUCE A. WHITE AND JOHN R. HARRISON
Chapter 39 Hormonal Regulation of Energy Metabolism
Introduction to the Endocrine System
Chapter 40 Hormonal Regulation of Calcium and Phosphate Metabolism
Chapter 41 The Hypothalamus and Pituitary Gland
The Thyroid Gland
The Adrenal Gland
Chapter 44 The Male and Female Reproductive Systems
Upon completion of this chapter, the student should be able to answer the following questions: 1.
Name the major endocrine glands and their hormonal product or products.
2.