skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: The interaction of cadmium with atrial natriuretic factor: A study in in vivo and in vitro models

Miscellaneous ·
OSTI ID:6913235

The involvement of atrial natriuretic factor (ANF) and its receptor in cadmium(Cd)-induced cardiovascular alterations and neurotoxicity is not known. This study examines the mechanisms underlying Cd-induced changes in the ANF peptide and its receptor in cardiovascular toxicity. In rats on short term Cd exposure (0.01, 0.1, 0.5 and 1.0 mg/kg, i.p., twice a day for 7 days and a maintenance period of 30 days), atrial ANF levels decreased significantly in the Cd 1 mg/kg group; plasma ANF levels were unchanged. Hypothalamic ANF content decreased significantly in 0.1-1.0 mg/kg Cd groups. Plasma renin activity and concentration were unchanged by Cd treatment. However, plasma aldosterone was significantly decreased in Cd 1.0 mg/kg group. Binding of [sup 125]I-ANF to its receptors in kidney, adrenals and aorta was not significantly altered. Cd treatment decreased urine volume indicating nephrotoxicity. Neuromodulation by ANF involved significant decrease in K[sup +] stimulated [[sup 3]H]NE release in rat hypothalamic slices. This action is proposed to be mediated by ANF-B receptors. 8Br-cGMP mimicked this action. In Cd treated animals (0.5 mg/kg twice a day for 7 days and maintained for 30 days), ANF neuromodulation in the hypothalmus was blocked, even though Cd content was undetectable. Cd preincubated (0.5 mM) slices showed a 49.1% block in neurotransmitter release indicating that Cd may block calcium channels leading to decreased K[sup +]-stimulated release of [[sup 3]H]NE. Hence, Cd-induced cardiovascular toxicity and neurotoxicity may be partly mediated by alteration in the release and possibly the synthesis of ANF peptide, disruption of ANF function through alterations in receptor dynamics and possibly alteration in cellular calcium homeostasis and membrane integrity. Central ANF function is sensitive to Cd and this effect may be partly resposible for the cardiovascular and neurotoxic responses to CD.

Research Organization:
Purdue Univ., Lafayette, IN (United States)
OSTI ID:
6913235
Resource Relation:
Other Information: Thesis (Ph.D.)
Country of Publication:
United States
Language:
English