Cadmium inhibition of respiration and potassium fluxes in oat root segments

Journal Article · Sat Jan 01 00:00:00 EST 1977 · Plant Physiol.; (United States)

OSTI ID:5196318

Keck, R W

Respiration in 1 cm oat root segments bathed in 1/4 strength Hoagland's solution was determined to be 230 ..mu..l O/sub 2//g fr wt/hr. When 1mM CdSO/sub 4/ was added the respiratory activity was retained at the control levels up to 2 hrs followed by an inhibition to 30 to 50% of control rates after 5 days. Influx and efflux of potassium (K) was monitored employing Rb/sup 86/ as a K marker. Short term (5-10 min) uptake kinetics of K are not altered in the presence or absence of Cd. After 60 min of Cd treatment the K uptake was 71% of control rates of 2 ..mu.. moles/g fr wt/hr. With a 2 hr Cd pretreatment K uptake was lowered to 10% of control rates. Cd pretreatment K uptake was lowered to 10% of control rates. Cd does not alter significantly either plasmalemma or tonoplast permeabilities as determined by Rb/sup 86/ efflux. A membrane bound, K stimulated, magnesium dependent, acid ATPase was assayed in the presence and absence of Cd. The stimulation due to K was 4.1 ..mu.. moles P released/mg protein/hr but in the presence of Cd and K stimulation was 12% of controls. Root segment ATP levels in control and 2 hrs of Cd treatment were determined by luciferin-luciferase assays. The control roots contained 10 n moles ATP/g fr wt/hr and the Cd treated roots contained 76% of these control values.

• Research Organization: IUPUI, Indianapolis, IN
• OSTI ID: 5196318
• Journal Information: Plant Physiol.; (United States), Vol. 59:6
• Country of Publication: United States
• Language: English

Related Subjects

63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
CADMIUM
BIOLOGICAL EFFECTS
RESPIRATION
INHIBITION
CADMIUM SULFATES
EXCRETION
METABOLISM
OATS
POTASSIUM
ROOTS
UPTAKE
ALKALI METALS
CADMIUM COMPOUNDS
CEREALS
CLEARANCE
ELEMENTS
GRASS
METALS
OXYGEN COMPOUNDS
PLANTS
SULFATES
SULFUR COMPOUNDS
560303* - Chemicals Metabolism & Toxicology- Plants- (-1987)