concept

mineralocorticoid receptor

Also known as: MR, mineralocorticoid receptors

Facts (10)

Sources

Allostasis revisited: A perception, variation, and risk framework frontiersin.org Frontiers Sep 28, 2022 10 facts

claimBaker et al. (2013, 2015) state that the divergence of mineralocorticoid receptors (MR) and glucocorticoid receptors (GR) occurred around the time when bony fish and cartilaginous fish diverged.

claimSapolsky et al. (2000) propose that mineralocorticoid receptors (MR) and glucocorticoid receptors (GR) have categorical differences in function: MR effects permissive roles at low hormone concentrations, while GR effects suppressive, stimulating, or preparative roles at stress-induced concentrations.

referenceModern elasmobranchs possess both glucocorticoid and mineralocorticoid receptor types, utilize corticosterone and 1α-hydroxycorticosterone as potential agonists, and express 11β-hydroxysteroid dehydrogenase (HSD) type 2 enzymes, as noted by Carroll et al. (2008) and Baker et al. (2013).

claimAlmost all modern vertebrates possess two types of corticosteroid receptors: mineralocorticoid receptors (MR) and glucocorticoid receptors (GR).

claimThe duplication and divergence of mineralocorticoid receptors (MR) and glucocorticoid receptors (GR) occurred approximately 450 million years ago, around the time bony fish and cartilaginous fish diverged.

claimE. M. Prager et al. localized mineralocorticoid receptors at mammalian synapses in a 2010 study published in PLoS One.

claimMineralocorticoid receptors (MR) and glucocorticoid receptors (GR) are homologous, having diverged approximately 450 million years ago around the time bony fish and cartilaginous fish diverged (Baker et al., 2013, 2015).

claimMineralocorticoid receptors (MR) bind both glucocorticoids and mineralocorticoids, whereas glucocorticoid receptors (GR) have lower affinity, bind exclusively to glucocorticoid hormones, and are nearly ubiquitously expressed (Baker et al., 2013).

claimThe distinction in binding affinity and function between mineralocorticoid receptors (MR) and glucocorticoid receptors (GR) is broadly supportive of a threshold-based activation model.

claimIndividual responsiveness to perturbation resistance potential (PRP) varies and influences the activation of mineralocorticoid vs glucocorticoid-type receptors, hormone metabolizing enzymes, and other downstream factors in target tissues.