Functional alpha(1)-adrenoceptor subtypes in human submandibular glands.
alpha(1)-Adrenoceptor has been discovered to exist in many human tissues and mediates important physiological functions. The purpose of this study was to detect the expression, distribution, and function of alpha(1)-adrenoceptor subtypes in human submandibular glands. alpha(1A)- and alpha(1B)-Adrenoceptor mRNAs were identified by reverse-transcription/polymerase chain-reaction (RT-PCR), and their proteins were detected by Western blotting. No expression of the alpha(1D)-adrenoceptor mRNA and protein was found. By in situ hybridization and immunohistochemistry, alpha(1A)- and alpha(1B)-adrenoceptor mRNAs and proteins were shown to be widespread in both ductal and acinar cells. By confocal microscopy, phenylephrine (stimulating both alpha(1A)- and alpha(1B)-adrenoceptors) or A61603 (alpha(1A)-selective agonist) induced an increase in intracellular calcium by 2.33 +/- 0.18-fold and 1.81 +/- 0.43-fold, respectively, while 5-methylurapidil (alpha(1A)-selective antagonist) partly blocked calcium mobility stimulated by phenylephrine. The results indicated that functional alpha(1A)- and alpha(1B)-adrenoceptors were expressed in human submandibular glands, and might contribute to the regulation of saliva synthesis and secretion.
Huang
Z
Z
Department of Oral and Maxillofacial Surgery, Peking University School and Hospital of Stomatology, Zhong Guan Cun South St. 22, 100081 Beijing, PRC.
Wu
L L
LL
Zhang
Y Y
YY
Gao
Y
Y
Yu
G Y
GY
D058646:Adrenergic alpha-1 Receptor Agonists; D058668:Adrenergic alpha-1 Receptor Antagonists; D000316:Adrenergic alpha-Agonists / Q000494:pharmacology; D000317:Adrenergic alpha-Antagonists / Q000494:pharmacology; D000368:Aged; D015153:Blotting, Western; D002118:Calcium / Q000378:metabolism; D002478:Cells, Cultured; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D008297:Male; D008875:Middle Aged; D010656:Phenylephrine / Q000494:pharmacology; D010879:Piperazines / Q000494:pharmacology; D012333:RNA, Messenger / Q000032:analysis; D018340:Receptors, Adrenergic, alpha-1 / Q000032:analysis*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013363:Submandibular Gland / Q000737:chemistry* / Q000502:physiology; D014018:Tissue Distribution
C547713:ADRA1A protein, human; C547716:ADRA1B protein, human; D058646:Adrenergic alpha-1 Receptor Agonists; D058668:Adrenergic alpha-1 Receptor Antagonists; D000316:Adrenergic alpha-Agonists; D000317:Adrenergic alpha-Antagonists; D010879:Piperazines; D012333:RNA, Messenger; D018340:Receptors, Adrenergic, alpha-1; C057446:5-methylurapidil; D010656:Phenylephrine; D002118:Calcium