Effects of neonatal methylmercury exposure on adrenergic-receptor binding sites in peripheral tissues of the developing rat

Technical Report · Wed Jan 01 00:00:00 EST 1986

OSTI ID:5468605

Slotkin, T A; Kavlock, R J; Cowdery, T; Orband, L; Bartolome, M

Neonatal exposure to methylmercury produces changes in patterns of tissue growth and function, in part, due to alterations in adrenergic neuronal input. To explore the mechanisms by which these changes come about, newborn rats were exposed to methylmercury (1 or 2.5 mg/kg/day) throughout the preweaning stage and the ontogeny of adrenergic receptor binding sites evaluated in liver, kidney, heart and lung, using (/sup 3/H)prazosin (alpha 1-receptors), (/sup 3/H)rauwolscine (alpha 2-receptors) and (/sup 125/I)pindolol (beta-receptors). In the kidney, methylmercury caused decreases in beta- and alpha 1-receptor binding and increases in alpha 2-binding, and the alterations persisted into adulthood; previous work has shown that beta-receptor-mediated responses are generally enhanced in methylmercury-exposed pups, and the down-regulation of beta-receptor binding thus probably represents a compensatory action secondary to alterations in post-receptor coupling mechanisms. The effects of methylmercury on hepatic adrenergic receptors were different from those seen in the kidney, with substantial elevations in beta- and alpha-receptor binding apparent in the preweaning stage; this agrees also with the differences in effects of the mercurial on trophic reactivity and growth in the two tissues.

• Research Organization: Duke Univ., Durham, NC (USA). Dept. of Pharmacology
• OSTI ID: 5468605
• Report Number(s): PB-88-144407/XAB
• Resource Relation: Other Information: Pub. in Toxicology, Vol. 41, 95-106(1986). See also report dated 1985, PB--86-120334
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
METHYLMERCURY
BIOLOGICAL EFFECTS
AUTONOMIC NERVOUS SYSTEM
IODINE 125
LABELLED COMPOUNDS
LABORATORY ANIMALS
NEONATES
PREGNANCY
RATS
TRITIUM
ANIMALS
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
DAYS LIVING RADIOISOTOPES
ELECTRON CAPTURE RADIOISOTOPES
HYDROGEN ISOTOPES
INTERMEDIATE MASS NUCLEI
IODINE ISOTOPES
ISOTOPES
LIGHT NUCLEI
MAMMALS
MERCURY COMPOUNDS
NERVOUS SYSTEM
NUCLEI
ODD-EVEN NUCLEI
ORGANIC COMPOUNDS
ORGANIC MERCURY COMPOUNDS
RADIOISOTOPES
RODENTS
VERTEBRATES
YEARS LIVING RADIOISOTOPES
550900* - Pathology
560300 - Chemicals Metabolism & Toxicology