title: Involvement of dopamine D1-like receptors in mediating increases in protein secretion from rabbit lacrimal gland.
abstract: To identify and localize the dopamine receptor subtypes in rabbit lacrimal gland which mediate protein secretion, the effects were determined of different dopamine receptor subtype agonists, antagonists, and a beta adrenergic antagonist on this process. Protein secretion into the medium was quantified with the Bradford assay. Dopamine increased protein secretion between 10(-7) and 10(-4)M, and it could be maintained for a subsequent 80 min. The relatively selective D1-like receptor agonist, SKF-38393 (10(-4)M) had a similar effect which was suppressed by the D1-like receptor antagonist, SCH-23390. However, neither the D2-like receptor agonist, quinpirole (10(-4)M), nor the selective D2-like receptor antagonist, sulpiride (10(-4)M) altered either the basal level or the stimulated response to dopamine. The dopamine (10(-4)M)-elicited increases in protein secretion were completely suppressed in the presence of either 10(-4)M propranolol or 10(-4)M bretylium. Protein secretion in rabbit lacrimal gland is mediated by dopaminergic nerves through stimulation of the presynaptic D1-like receptor.
authors.affiliation: Santen Pharmaceutical Co., Ltd., Nara Research and Development Center, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Murakami
authors.forename: M
authors.initials: M
authors.lastname: Nakamura
authors.forename: T
authors.initials: T
authors.lastname: Fujihara
authors.forename: K
authors.initials: K
authors.lastname: Nakata
mesh_terms: D015647:2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benzazepine / Q000494:pharmacology; D000319:Adrenergic beta-Antagonists / Q000494:pharmacology*; D000818:Animals; D001552:Benzazepines / Q000494:pharmacology; D001949:Bretylium Compounds / Q000494:pharmacology; D015259:Dopamine Agents / Q000494:pharmacology*; D018491:Dopamine Agonists / Q000494:pharmacology; D018492:Dopamine Antagonists / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004347:Drug Interactions; D005136:Eye Proteins / Q000378:metabolism*; D007765:Lacrimal Apparatus / Q000378:metabolism*; D011433:Propranolol / Q000494:pharmacology; D019257:Quinpirole / Q000494:pharmacology; D011817:Rabbits; D017447:Receptors, Dopamine D1 / Q000145:classification / Q000502:physiology*; D013469:Sulpiride / Q000494:pharmacology; D013997:Time Factors
chemical_list: D000319:Adrenergic beta-Antagonists; D001552:Benzazepines; D001949:Bretylium Compounds; D015259:Dopamine Agents; D018491:Dopamine Agonists; D018492:Dopamine Antagonists; D005136:Eye Proteins; D017447:Receptors, Dopamine D1; D019257:Quinpirole; D015647:2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benzazepine; D013469:Sulpiride; D011433:Propranolol; C045166:bretylium