Effect of ionizing radiation on sympathetic nerve function in rat parotid glands.
Ionizing radiation (IR) irreversibly damages salivary glands. The pathologic mechanism is unknown. Previously we reported that parotid serous acinar cells may not be the primary site of damage by IR. The purpose of this study was to determine if IR alters sympathetic nerve function in rat parotid glands. Male adult rats received a single dose of radiation (20 Gy) to the head and neck. Three days after IR, parotid saliva secretion induced by norepinephrine (NE) was completely blocked. Catecholamine uptake and metabolism were studied by injecting [3H] dopamine ([3H]DA) into irradiated rats, as a bolus. After 60 min, animals were sacrificed and the parotid gland, submandibular gland, and left ventricle removed. Tissue contents of [3H]DA and [3H]NE, identified by HPLC, were unaffected by IR. The results indicate that IR abolishes acinar responsiveness to NE without affecting parotid sympathetic nerve function.
Kohn
W G
WG
Clinical Investigations and Patient Care Branch, National Institute of Dental Research, Bethesda, Maryland 20892.
Grossman
E
E
Fox
P C
PC
Armando
I
I
Goldstein
D S
DS
Baum
B J
BJ
D000818:Animals; D004298:Dopamine / Q000097:blood / Q000378:metabolism; D008297:Male; D009638:Norepinephrine / Q000097:blood / Q000378:metabolism / Q000494:pharmacology; D010306:Parotid Gland / Q000187:drug effects / Q000294:innervation* / Q000378:metabolism / Q000528:radiation effects; D011829:Radiation Dosage; D011839:Radiation, Ionizing; D051381:Rats; D011919:Rats, Inbred Strains; D012463:Saliva / Q000187:drug effects / Q000378:metabolism / Q000528:radiation effects; D012636:Secretory Rate / Q000187:drug effects / Q000528:radiation effects; D013564:Sympathetic Nervous System / Q000187:drug effects / Q000528:radiation effects*; D014316:Tritium
D014316:Tritium; D004298:Dopamine; D009638:Norepinephrine