title: Secretory effect of prostaglandins on the rabbit lacrimal gland in vivo.
abstract: Fluid secretion from the cannulated excretory duct of the rabbit lacrimal gland was collected in microcapillary pipette at 10 min intervals. Secretion rate and electrolyte concentrations (Na+, K+ and Cl-) in the lacrimal fluid samples were determined before and after injections of small doses of prostaglandins (PGE1, PGE2, PGF1 alpha, PGF2 alpha, 15 epi-PGF2 alpha, PGF2 beta, PGA1 & PGA2) into the external maxillary artery. Only PGE1 had a dose-dependent stimulatory effect on the lacrimal gland secretion. The maximum secretion rate which was induced by PGE1 (25 micrograms/kg) was 7.2 +/- 0.9 microliters/10 min. Na+ concentration in the fluid secretion stimulated by PGE1 was increased; however, K+ and Cl- concentrations were not changed. Pretreatment with atropine (50 micrograms/kg, I.A.) failed to prevent the stimulatory effect of low doses of PGE1. On the other hand, the secretory responses were abolished when propanolol (3 mg/kg, I.A.) was administered prior to PGE1. The results suggest that fluid secretion of the rabbit lacrimal gland in response to PGE1 may be caused by excitation of the sympathetic ganglia and/or by direct action on beta-receptors in the acinar cells.
mesh_terms: D000818:Animals; D001285:Atropine / Q000494:pharmacology; D002712:Chlorides / Q000378:metabolism; D005260:Female; D007765:Lacrimal Apparatus / Q000187:drug effects* / Q000378:metabolism; D008297:Male; D011188:Potassium / Q000378:metabolism; D011433:Propranolol / Q000494:pharmacology; D011459:Prostaglandins E, Synthetic / Q000494:pharmacology*; D011465:Prostaglandins, Synthetic / Q000494:pharmacology; D011817:Rabbits; D011943:Receptors, Adrenergic, beta / Q000187:drug effects; D012964:Sodium / Q000378:metabolism; D013666:Tears / Q000378:metabolism
chemical_list: D002712:Chlorides; D011459:Prostaglandins E, Synthetic; D011465:Prostaglandins, Synthetic; D011943:Receptors, Adrenergic, beta; D001285:Atropine; D012964:Sodium; D011433:Propranolol; D011188:Potassium