Cell-enlargement-related polypeptides are induced via beta(1)-adrenoceptors in mouse parotids.
Induction of cell and gland enlargement (growth-in-size) and induction of a group of secretory polypeptides (polypeptides C-G) seem to occur in close relationship in mouse parotid glands stimulated chronically by the nonselective beta-adrenergic agonist isoproterenol. To determine whether beta(1), beta(2), or both subtypes of beta-adrenergic receptors are involved in those responses, dose-dependency studies were carried out during a 7-day period of daily stimulations to assess the relative abilities of the selective beta-adrenergic agonists dobutamine (beta(1)) and salbutamol (beta(2)) to induce polypeptides C-G and growth-in-size. The relative abilities of the selective beta-adrenoceptor antagonists atenolol (beta(1)) and I.C.I. 118.551 (beta(2)) to interfere with the induction of both responses by chronic treatment with the various beta-adrenergic agonists were also studied. Parotid growth-in-size was assessed by evaluating wet weight, whole protein content, and light microscopy histology. The presence of polypeptides C-G was evaluated after SDS-polyacrylamide gel electrophoresis and Coomassie blue staining. Under these experimental conditions, dobutamine was found to be at least one order of magnitude more potent than salbutamol at inducing growth-in-size. Dobutamine was also found to be clearly stronger than salbutamol as an inducer of polypeptides C-G. On the other hand, atenolol was more effective than I.C.I. 118.551 at preventing the induction of polypeptides C-G and growth-in-size by isoproterenol, dobutamine, or salbutamol. Taken together, these results suggest that in mouse parotid glands, polypeptides C-G and growth-in-size are induced preferentially via adrenergic receptors of the beta(1)-subtype.
González
M J
MJ
Institute for Biomedical Sciences, Faculty of Medicine, University of Chile, Santiago 7, Chile.
Peña y Lillo
S
S
Alliende
C
C
López Solís
R O
RO
D000318:Adrenergic beta-Agonists / Q000494:pharmacology; D000319:Adrenergic beta-Antagonists / Q000494:pharmacology; D000420:Albuterol / Q000494:pharmacology; D000818:Animals; D001262:Atenolol / Q000494:pharmacology; D048429:Cell Size / Q000187:drug effects; D004280:Dobutamine / Q000494:pharmacology; D006984:Hypertrophy; D007545:Isoproterenol / Q000494:pharmacology; D008297:Male; D051379:Mice; D010306:Parotid Gland / Q000187:drug effects / Q000378:metabolism* / Q000473:pathology*; D010455:Peptides / Q000737:chemistry / Q000378:metabolism*; D011412:Propanolamines / Q000494:pharmacology; D018342:Receptors, Adrenergic, beta-1 / Q000378:metabolism*
D000318:Adrenergic beta-Agonists; D000319:Adrenergic beta-Antagonists; D010455:Peptides; D011412:Propanolamines; D018342:Receptors, Adrenergic, beta-1; D004280:Dobutamine; C026777:ICI 118551; D001262:Atenolol; D007545:Isoproterenol; D000420:Albuterol