Caveolae stimulation

Other pinocytotic pathways also exist that do not depend on either caveolae or clathrin, although these are not as well defined [55]. Specific receptors continue to be internalized in the absence of clathrin or caveolin and these pathways can be monitored by following glycosyl phos-phatidylinositol (GPI (-anchored proteins. Nonclathrin, noncaveolin pathways may also be responsible for the reuptake of membrane in neuroendocrine cells after stimulated secretion. Some, but not all, of these pathways appear to require dynamin. 

Kim HP, Lee JY, Jeong JK, Bae SW, Lee HK, Jo I (1999) Nongenomic stimulation of nitric oxide release by estrogen is mediated by estrogen receptor alpha localized in caveolae. Biochem Biophys Res Commun 263(l) 257-262... 

PMA inhibitor Protein kinase C activator stimulation of caveolae uptake Should be an selective 48,68 ... 

Nystatin Bind cholesterol inhibitor for caveolae, but also stimulate macropinocytosis Block cholesterol-sensitive 60 ... 

Phorbol esters are described as being protein kinase C activators and should be selective inhibitors for caveolae uptake [1 pM Phorbol 12-myristate 13-acetate (PMA) for 30 minutes] (48,68). The inhibition occurs as quickly as five minutes after adding PMA to cell culture medium and is not reversible within five hours (MA104 cells). However, PMA has several other effects on several other pathways. An example of this is that it has been described to stimulate macropinocytosis and transcytosis (see the following). 

The serine/threonine phosphatase inhibitor okadaic acid (incubation time and concentration vary from 10 nM, 30 minutes to 1 pM, 1 hour at 37°C) leads to selective stimulation of caveolae uptake (18,64). 

Ishizaka, N., Griendling, K. K., Lassegue, B., et al. 1998. Angiotensin II type 1 receptor relationship with caveolae and caveolin after initial agonist stimulation. Hypertension 32 459-466. 

Feron O, Smith TW, Michel T, Kelly RA. Dynamic targeting of the agonist-stimulated m2 muscarinic acetylcholine receptor to caveolae in cardiac myocytes. J Biol Chem 1997 272 17,744-17,748. 

Gustavsson, j., Parpal, S., and StrAl-EORS, P. Insulin-stimulated glucose uptake involves the transition of glucose transporters to a caveolae-rich fraction within the plasma membrane implications for type II diabetes. Mol. Med.,... 

Despite a few claims that growth factor receptors are associated with caveolae, and the fact that tyrosine kinase phosphorylation of receptor in caveolae is rapidly induced upon PDGF or EGF stimulation of cells [16, 17], growth factor receptors are absent or barely detectable in GSL microdomain. A major question therefore remains How do GSLs affect growth factor receptor function We have no information as to whether ... 

Liu P, Ying Y, Ko Y-G, Anderson RGW Localization of platelet-derived growth factor-stimulated phosphorylation cascade to caveolae. J. Biol. Chem. 1996 271 10299-10303. 

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