Physiology of renal hormones

This chapter is related to Section U1(vi) from the 2017 CICM Primary Syllabus, which asks the exam candidate to  "describe the control, secretions and functions of renal and adrenal hormones". It is recognisably a duplication of other primary exam material, such as Section H1(iv) from the renal collection ("outline the endocrine functions of the kidney") and Section G5(iv) from the cardiovascular system ("explain the humoral regulation of blood volume and flow"). 

The reader is referred to the page on the endocrine functions of the kidney and the page dealing with the humoral regulation of blood volume (which involves a lot of renin and angiotensin). More detail is available over there. Here, only the barest summary is reproduced, to wreck some SEO and simplify revision:

  • Hormones which are secreted by the kidney
    • Erythropoietin
      • Secreted from modified cortical fibroblasts
      • Stimulated by hypoxia and angiotensin II
      • Inhibited by inflammatory cytokines
      • Effect is increase in the rate of red cell production and maturation
    • Renin
      • Secreted from juxtaglomerular cells
      • Stimulated by hypotension, sympathetic activation and decreased renal salt delivery
      • Inhibited by angiotension II and normalised blood pressure/volume
      • Effect is to activate RAAS, producing vasoconstriction and salt/water retention
    • Thrombopoietin
      • Secreted from the proximal convoluted tubule
      • Stimulated by thrombocytopenia and inflammatory cytokines
      • Inhibited by itself (negative feedback loop)
      • Effect is to stimulate megacaryocytes and increase platelet production
    • Urodilatin
      • Secreted from DCT cells, directly into the tubule
      • Stimulated (probably) by increased sodium deliery
      • Inhibited (presumably) by decreased sodium delivery
      • The effect to increase sodium reabsoprtion in the collecting duct
  • Hormones which are modified by the kidney
    • Calcitriol (active form of Vitamin D)
      • Modified in the proximal tubule
      • Increased  conversion is stimulated by hypocalcemia, PTH and low vitamin D levels
      • Conversion is inhibited by hypercalcemia, low PTH and high vitamin D levels
      • Physiological role is to increase calcium levels by increasing renal/GI absorption and enhancing osteoclast activity
  • Hormones which are cleared or metabolised by the kidney
    • Insulin
      • 90% cleared by the kidney (proximal tubule)
    • Gastrin
      • 30% cleared by the kidney (probably also proximal tubule)
    • Other hormones:
      • PTH
      • Vasopressin
      • Oxytocin
      • TSH
      • Growth hormone
      • Luteinising hormone

In terms of exam readiness, renal hormones only been specifically been asked about, once, as a part of Question 4 from the first paper of 2017. On the other hand, adrenal hormones are a huge favourite with SAQ writers, as the influence of this group covers half of the ICU drug cupboard (catecholamines, glucocorticoids and mineralocorticoids). Most of these questions understandably have a thoroughly pharmacological inclination, asking the candidate to compare one steroid to another. For this reason, adrenal hormone physiology has been banished to a series of chapters all on its own, where this exam-relevant material is dealt with more thoroughly, and from the viewpoint of a critical care prescriber.

References

Stathatos, Nikolaos. "Thyroid physiology." Medical Clinics 96.2 (2012): 165-173.

Stathatos, Nikolaos. "Anatomy and physiology of the thyroid gland." The thyroid and its diseases. Springer, Cham, 2019. 3-12.

Maenhaut, C., et al. "Ontogeny, anatomy, metabolism and physiology of the thyroid." Endotext [Internet] (2015).

Crowner, Anne, et al. "Rediscovering the axolotl as a model for thyroid hormone dependent development." Frontiers in Endocrinology 10 (2019): 237.

Fujita, Hisao. "Fine structure of the thyroid gland." International review of cytology 40 (1975): 197-280.

Fujita, Hisao. "Fine structure of the thyroid follicle." Ultrastructure of endocrine cells and tissues. Springer, Boston, MA, 1984. 265-275.

Ericson, Lars E. "Exocytosis and endocytosis in the thyroid follicle cell." Molecular and cellular endocrinology 22.1 (1981): 1-24.

Hartoft‐Nielsen, M. L., et al. "Estimation of number of follicles, volume of colloid and inner follicular surface area in the thyroid gland of rats." Journal of anatomy 207.2 (2005): 117-124.

Mense, Mark G., and Gary A. Boorman. "Thyroid gland." Boorman's Pathology of the Rat. Academic Press, 2018. 669-686.

Hayden, L. J., J. M. Shagrin, and J. A. Young. "Micropuncture investigation of the anion content of colloid from single rat thyroid follicles." Pflügers Archiv 321.2 (1970): 173-186.

Tegler, Lennart, et al. "Thyroid blood flow rate in man. Electromagnetic flowmetry during operation in euthyroid normal gland, nontoxic goiter, and hyperthyroidism." Journal of Endocrinological Investigation 4.3 (1981): 335-341.

Vidal Fortuny, Jordi, et al. "Surgery of the thyroid: recent developments and perspective." Swiss medical weekly 145 (2015): w14144.

Gross, Samuel David. A System of surgery v. 1. Vol. 1. HC Lea's son, 1882.

Holzer, Guillaume, et al. "Thyroglobulin represents a novel molecular architecture of vertebrates." Journal of Biological Chemistry 291.32 (2016): 16553-16566.

Coscia, Francesca, et al. "The structure of human thyroglobulin." Nature 578.7796 (2020): 627-630.

Carvalho, Denise P., and Corinne Dupuy. "Thyroid hormone biosynthesis and release." Molecular and cellular endocrinology 458 (2017): 6-15.

Senou, Maximin, et al. "Role of caveolin-1 in thyroid phenotype, cell homeostasis, and hormone synthesis: in vivo study of caveolin-1 knockout mice." American Journal of Physiology-Endocrinology and Metabolism 297.2 (2009): E438-E451.

Colucci, Philippe, et al. "A review of the pharmacokinetics of levothyroxine for the treatment of hypothyroidism.European Endocrinology 9.1 (2013): 40.

Hennemann, Georg, et al. "Plasma membrane transport of thyroid hormones and its role in thyroid hormone metabolism and bioavailability." Endocrine reviews 22.4 (2001): 451-476.

Sinha, Rohit, and Paul M. Yen. "Cellular action of thyroid hormone." Endotext [Internet] (2018).

Malik, Furrukh S., et al. "Intravenous thyroid hormone supplementation in heart failure with cardiogenic shock." Journal of Cardiac Failure 5.1 (1999): 31-37.

Herget, J., et al. "Thyroxine treatment increases the hypoxic pulmonary vasoconstriction in isolated lungs from thyroidectomized rats.Bulletin Europeen de Physiopathologie Respiratoire 23.3 (1987): 217-221.

Grunstein, Ronald R., and Colin E. Sullivan. "Sleep apnea and hypothyroidism: mechanisms and management." The American journal of medicine 85.6 (1988): 775-779.

Dempsey, G. A., et al. "Anaesthesia for massive retrosternal thyroidectomy in a tertiary referral centre." British journal of anaesthesia 111.4 (2013): 594-599.

Prezioso, Giovanni, Cosimo Giannini, and Francesco Chiarelli. "Effect of thyroid hormones on neurons and neurodevelopment.Hormone research in paediatrics 90.2 (2018): 73-81.

Bernal, Juan. "Thyroid hormone receptors in brain development and function." Nature clinical practice Endocrinology & metabolism 3.3 (2007): 249-259.

Anderson, Grant W. "Thyroid hormones and the brain." Frontiers in neuroendocrinology 22.1 (2001): 1-17.

Krishna MCS, Kumara HDS, Vishwanath HL, et al. " The Electrolytes And Hypothyroidism - A Case Control Study". Biochem Ind J. 2018;12(2):131

Mariani, Laura H., and Jeffrey S. Berns. "The renal manifestations of thyroid disease.Journal of the American Society of Nephrology 23.1 (2012): 22-26.

Daher, Ronald, et al. "Consequences of dysthyroidism on the digestive tract and viscera." World journal of gastroenterology: WJG 15.23 (2009): 2834.

Ahmed, Sawer Sabri, and Ayad Ahmad Mohammed. "Effects of thyroid dysfunction on hematological parameters: Case controlled study." Annals of Medicine and Surgery 57 (2020): 52-55.

Montesinos, María del Mar, and Claudia Gabriela Pellizas. "Thyroid hormone action on innate immunity.Frontiers in Endocrinology 10 (2019): 350.

Mullur, Rashmi, Yan-Yun Liu, and Gregory A. Brent. "Thyroid hormone regulation of metabolism." Physiological reviews (2014).

Jansson, Svante, et al. "Oxygen consumption in patients with hyperthyroidism before and after treatment with β-blockade versus thyrostatic treatment: A Prospective Randomized Study." Annals of surgery 233.1 (2001): 60.

Sadek, Samiaa Hamdy, Walaa Anwar Khalifa, and Ahmad Metwally Azoz. "Pulmonary consequences of hypothyroidism.Annals of thoracic medicine 12.3 (2017): 204.

Iwen, K. Alexander, Rebecca Oelkrug, and Georg Brabant. "Effects of thyroid hormones on thermogenesis and energy partitioning." Journal of Molecular Endocrinology 60.3 (2018): R157-R170.

Clarke, Ronald J., et al. "Quantitative calculation of the role of the Na+, K+-ATPase in thermogenesis." Biochimica et Biophysica Acta (BBA)-Bioenergetics 1827.10 (2013): 1205-1212.

Rolfe, D. F., and Guy C. Brown. "Cellular energy utilization and molecular origin of standard metabolic rate in mammals." Physiological reviews 77.3 (1997): 731-758.

Visser, Theo J. "Regulation of thyroid function, synthesis and function of thyroid hormones." Thyroid Diseases: Pathogenesis, Diagnosis, and Treatment (2018): 3-32.

Larsen, P. Reed, J. Enrique Silva, and Michael M. Kaplan. "Relationships between circulating and intracellular thyroid hormones: physiological and clinical implications." Endocrine reviews 2.1 (1981): 87-102.

SAWIN, CLARK T., JEROME M. HERSHMAN, and INDER J. CHOPRA. "The comparative effect of T4 and T3 on the TSH response to TRH in young adult men." The Journal of Clinical Endocrinology & Metabolism 44.2 (1977): 273-278.