TABLE 3

Site of action for pharmacological agents acting on group I mGlu receptors in the periphery

This table does not include studies performed in sensory cells.

Agent	Site of Action	Effect	References
Agonists
ACPD^{^a}	Adrenal glands	Increased secretion of catecholamines	González et al., 1998
	Testis	Increased inositol phospholipid hydrolysis	Storto et al., 2001
	Enteric neurons	Activation of depolarizing response
	Peripheral T cells	Increased survival to apoptosis induced by anti-CD3	Ren et al., 2000
	Hepatocytes	Increased inositol monophosphate formation and hypoxia-induced cell damage	Chiocchetti et al., 2006
	Osteoblasts	Reduced NMDA-induced current	Storto et al., 2000b; Sureda et al., 1997
			Gu and Publicover, 2000
CHPG^{^b}	Peripheral T cells	Increased survival to apoptosis induced by anti-CD3	Chiocchetti et al., 2006; Pacheco et al., 2004
	Enteric neurons	Activation of depolarizing response	Liu and Kirchgessner, 2000
	Enteric glia	Increased expression of c-Fos and activation of ERK1/2	Nasser et al., 2007
DHPG	Chromaffin cells	Increased secretion of catecholamines	Arce et al., 2004
	Pancreatic β cells	Increased release of insulin at low glucose concentrations	Brice et al., 2002
	Duodenum	Increased intracellular pH	Akiba et al., 2009
	Enteric neurons	mGlu5 internalization; activation of depolarization; suppression of slow EPSPs	Liu and Kirchgessner, 2000; Ren et al., 1999; 2000
	Peripheral T cells	Increased survival to apoptosis induced by anti-CD3	Chiocchetti et al., 2006; Pacheco et al., 2004
	Endothelial cells	Increased paracellular permeability; prevents oxidative damage	Collard et al., 2002; Lin and Maiese, 2001
	Cartilage	Decreased mineralization	Wang et al., 2005
	Melanocytes	Impaired viability in confluent cultures; proliferation in subconfluent cultures	Frati et al., 2000
	Tumor cells	Increased cell migration, invasion, and adhesion	Park et al., 2007
Quisqualate	Hepatocytes	Increased inositol monophosphate formation and hypoxia-induced cell damage	Storto et al., 2000b; Sureda et al., 1997
	Heart	Increased PLC activity	Iglesias et al., 2007
	Melanocytes	Impaired viability in confluent cultures; proliferation in subconfluent cultures	Frati et al., 2000
	Stem cells	Increased intracellular Ca²⁺ levels	Cappuccio et al., 2005
	Peripheral T cells	Increased survival to apoptosis induced by anti-CD3	Chiocchetti et al., 2006
Antagonists
AIDA	Duodenum	Decreases glutamate-induced alkalinization	Akiba et al., 2009
	Ileum	Suppression of DHPG-induced depolarizing response	Liu and Kirchgessner, 2000
	Peripheral T cells	Inhibition of prosurvival effect induced by quisqualate	Chiocchetti et al., 2006
BAY36-7620^{^c}	Tumor cells	Reduction in cell proliferation	Namkoong et al., 2007
CPCCOEt^{^c}	Peripheral T cells	Impaired cytokine production	Pacheco et al., 2006
	Testis	Inhibition of the ACPD-induced inositol phospholipid hydrolysis	Storto et al., 2001
LY367385^{^c}	Tumor cells	Reduction in cell proliferation	Namkoong et al., 2007
MPEP^{^b}	Peripheral T cells	Increased IL-6 production and inhibition of Glu-induced survival to apoptosis	Chiocchetti et al., 2006; Pacheco et al., 2006
	Testis	Inhibition of the ACPD-induced inositol phospholipid hydrolysis	Storto et al., 2001
	Pancreas	Inhibition of Glu-induced insulin secretion and of glucagon response to insulin	Storto et al., 2006
	Hepatocytes/ liver	Protection against hypoxia-, acetaminophen-, and LPS-induced damage	Jesse et al., 2009; Storto et al., 2000b, 2003
	Enteric neurons	Reduction of glutamate-induced depolarizing response	Liu and Kirchgessner, 2000
	Melanocytes	Prevention of quisqualate-induced effects	Frati et al., 2000
	Stem cells	Reduction in markers of undifferentiated state	Cappuccio et al., 2005; Spinsanti et al., 2006
	Tumor cells	Inhibition of DHPG-induced cell migration, invasion, and adhesion	Park et al., 2007
PHCCC^{^d}	Endothelial cells	Attenuated glutamate-mediated increases in paracellular permeability	Collard et al., 2002
	Tumor cells	Reduction of proliferation in vitro and tumor mass growth in vivo	Namkoong et al., 2007
S-4-CPG	Enteric neurons	Reduction of DHPG-induced depolarization; suppression of Glu effect on EPSPs	Hu et al., 1999; Liu and Kirchgessner, 2000; Ren et al., 1999; 2000
	Enteric glia	Abolished intracellular signaling induced by CHPG	Nasser et al., 2007

CHPG, (R,S)-2-chloro-5-hydroxyphenylglycine; CPCCOEt, 7-(hydroxyimino)cyclopropa[b]chromen-1α-carboxylate ethyl ester; Quisqualate, (l)-(+)-α-amino-3,5-dioxo-1,2,4-oxadiazolidine-2-propanoic acid; S-4-CPG, (S)-4-carboxyphenylglycine.
↵a Also activates mGlu receptors from group II.
↵b Specific for mGlu5 receptor.
↵c Specific for mGlu1 receptor.
↵d Also activates mGlu4 receptor.