Physiological role of alpha-adrenoceptors in salivary secretion
Acta odontol. latinoam
; 5(1): 31-8, 1990.
Article
in Es
|
LILACS-Express
| LILACS, BINACIS
| ID: biblio-1157670
Responsible library:
AR29.1
Localization: [{"text": "AR29.1"}]
ABSTRACT
The submaxillary gland (SM) of rat is innervated by both branches of the autonomic nervous system. Secretion is mediated by the activation of both muscarinic-cholinergic and alpha/beta adrenergic receptors. Studies of the relative affinity of pharmacological agonists and antagonists have warranted a subclassification of alpha adrenoceptors into types alpha 1 and alpha 2. Our studies involve an analysis of the physiologic role of both types of alpha adrenoceptors in salivary secretion. Dose response curves (DRC) to noradrenaline (NA) following administration of alpha adrenoceptor antagonists, i.e. prazosin (alpha 1 antagonist), yohimbine (alpha 2 antagonist) and phentolamine (alpha 1-alpha 2 antagonist) were constructed. Our results demonstrate that prazosin is 100 times more effective than yohimbine in blocking NA-induced salivary secretion. The alpha 2 agonist clonidine (10 micrograms/Kg) blocked the DRCs to methacholine, noradrenaline and substance P-but failed to modify the DRC to isoproterenol. Our results reveal that the subtypes of alpha adrenergic receptors play antagonistic roles in salivary secretion. Alpha 1 stimulation elicits profuse salivary secretion whereas alpha 2 stimulation inhibits salivary secretion induced by 3 different types of agonists, i.e. alpha 1, muscarinic-cholinergic and neurokininergic without affecting beta receptor mediated responses.
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Collection:
01-internacional
Database:
BINACIS
/
LILACS
Language:
Es
Journal:
Acta odontol. latinoam
Journal subject:
ODONTOLOGIA
Year:
1990
Document type:
Article
Country of publication:
Argentina
/