Effect of extracellular magnesium on secretagogue-evoked amylase secretion in the isolated rat parotid gland segments.
This study investigates the effect of perturbation of extracellular magnesium [Mg2+]o on basal and acetylcholine (ACh), noradrenaline (NA) and phenylephrine (PHE)-evoked amylase secretion from isolated rat parotid gland segments. Both zero (0 mM) and elevated (5 mM and 10 mM) [Mg2+]o can significantly (P < 0.05) inhibit basal and secretagogue-evoked amylase secretion compared to the responses obtained in normal (1.1 mM) [Mg2+]o. The inhibitory effect of zero [Mg2+]o was more pronounced compared 10 mM [Mg2+]o. A concentration of 5 mM, [Mg2+]o was less effective at a secretagogue concentration of 10(-5) M but more pronounced in inhibiting amylase secretion when the concentration of the secretagogue was reduced to 10(-6) M. The results indicate that both hypo and hypermagnesaemia are associated with reduced salivary amylase secretion and both conditions may be associated with 'the dry mouth syndrome'.
Mata
Antonio
A
Department of Oral Biology, ISCS-Sul, Monte de Caparica, Portugal. admata2@yahoo.com
Marques
Duarte
D
Mesquita
Maria F
MF
Singh
Jaipaul
J
D000109:Acetylcholine / Q000494:pharmacology; D000681:Amylases / Q000378:metabolism*; D000818:Animals; D005260:Female; D066298:In Vitro Techniques; D008274:Magnesium / Q000494:pharmacology*; D008297:Male; D009638:Norepinephrine / Q000494:pharmacology; D010306:Parotid Gland / Q000187:drug effects / Q000201:enzymology* / Q000378:metabolism*; D010656:Phenylephrine / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D013268:Stimulation, Chemical
D010656:Phenylephrine; D000681:Amylases; D008274:Magnesium; D000109:Acetylcholine; D009638:Norepinephrine