Regulation of Formation and Proposed Structure of the Factor Inhibiting the Release of Melanocyte-stimulating Hormone
Overview
Authors
Affiliations
Microsomal preparations from the stalk median eminence of female rats are shown to contain an enzymic activity that is responsible for the formation of MSH-release-inhibiting factor (MSH-R-IF). The amount of this activity remains constant throughout the estrous cycle. The corresponding mitochondrial preparations from the stalk median eminence contain another enzymic principle, estrous cycle-dependent, which competes with the enzyme present in the microsomal preparation for the same "substrate", and can thereby prevent the formation of MSH-R-IF. Several neurohypophyseal hormones, analogs, and peptide intermediates have been tested for their intrinsic MSH-R-IF activity and for their ability to be transformed into MSH-R-IF by incubation with microsomal preparations of stalk median eminence from male rats; it is concluded that the enzyme responsible for the formation of MSH-R-IF is an exopeptidase and that the release-inhibiting factor itself is a tripeptide. Oxytocin is converted by the incubation to (L)-prolyl-(L)-leucylglycinamide; nanogram amounts of this tripeptide inhibit the release of MSH from the pituitary both in vivo and in vitro.
Roots and early routes of neuroendocrinology.
Rodriguez E, Guerra M, Blazquez J Cell Tissue Res. 2025; .
PMID: 39883141 DOI: 10.1007/s00441-024-03928-0.
Silva-Reis S, Correia X, Costa-Almeida H, Pires-Lima B, Maronde D, Costa V ACS Med Chem Lett. 2023; 14(12):1656-1663.
PMID: 38116429 PMC: 10726482. DOI: 10.1021/acsmedchemlett.3c00264.
In vitro permeation of micronized and nanonized alaptide from semisolid formulations.
Opatrilova R, Cernikova A, Coufalova L, Dohnal J, Jampilek J ScientificWorldJournal. 2014; 2013:787283.
PMID: 24453907 PMC: 3881672. DOI: 10.1155/2013/787283.
Mass spectrometric quantification of MIF-1 in mouse brain by multiple reaction monitoring.
Kheterpal I, Kastin A, Mollah S, Yu C, Hsuchou H, Pan W Peptides. 2009; 30(7):1276-81.
PMID: 19540426 PMC: 3521590. DOI: 10.1016/j.peptides.2009.04.004.
Plasma beta-lipotropin levels in Parkinson's disease.
Wiesen M, Yahr M, Krieger D J Neural Transm. 1982; 53(1):75-82.
PMID: 6278076 DOI: 10.1007/BF01243521.