Nitric Oxide Synthase Isoform Activities in Kidney of Dahl Salt-Sensitive Rats
- 1 December 1995
- journal article
- research article
- Published by Wolters Kluwer Health in Hypertension
- Vol. 26 (6) , 1030-1034
- https://doi.org/10.1161/01.hyp.26.6.1030
Abstract
Abstract An abnormal l -arginine–nitric oxide axis has been suggested to be relevant to the genesis of salt-sensitive hypertension. In the present study we investigated the activities of three isoforms of nitric oxide synthase (NOS) in the kidney of Dahl salt-sensitive and salt-resistant rats. Five-week-old Dahl Iwai salt-sensitive (n=9) and salt-resistant (n=10) rats were maintained on a high salt diet (4% sodium chloride) for 4 weeks. We measured calcium-dependent and calcium-independent NOS activities in each particulate and soluble fraction of kidney by conversion of l -[ 3 H]arginine to l -[ 3 H]citrulline. Systolic blood pressure was elevated significantly ( P <.001) in salt-sensitive but not salt-resistant rats. Calcium-dependent NOS activity in the soluble fraction was significantly lower in salt-sensitive rats than in salt-resistant rats (25.8±9.0 versus 48.2±19.2 disintegrations per microgram protein, respectively; P <.01). There were no differences in calcium-dependent NOS activity in the particulate fraction and calcium-independent NOS activity in the soluble fraction between groups. Renal norepinephrine content was lower in salt-sensitive rats than in salt-resistant rats ( P <.05) and was positively correlated with calcium-dependent NOS activity in the soluble fraction ( P <.01). Although no differences in endothelial and inducible-type NOS activity were observed a significant reduction in calcium-dependent NOS activity in the soluble fraction of the kidney of salt-sensitive rats suggests that the decreased neural-type NOS activity may in part be involved in the mechanism of salt-sensitive hypertension, possibly through alterations in renal sympathetic nervous activity and sodium handling.Keywords
This publication has 23 references indexed in Scilit:
- Nitric oxide modulates sympathetic neurotransmission at the prejunctional levelMicroscopy Research and Technique, 1994
- Endogenous nitric oxide synthesis determines sensitivity to the pressor effect of saltKidney International, 1994
- Nitric oxide synthase isozymes. Characterization, purification, molecular cloning, and functions.Hypertension, 1994
- Blockade of distal nephron sodium transport attenuates pressure natriuresis in dogs.Hypertension, 1994
- Hypertension induced by nitric oxide synthesis inhibition is renal nerve dependent.Hypertension, 1994
- L-arginine administration normalizes pressure natriuresis in hypertensive Dahl rats.Hypertension, 1993
- Role of nitric oxide synthesis in salt-sensitive hypertension in Dahl/Rapp rats.Hypertension, 1993
- Neural mechanism of hypertension by nitric oxide synthase inhibitor in dogs.Hypertension, 1993
- Abnormal adrenal catecholamine synthesis in salt-sensitive Dahl rats.Hypertension, 1987
- A rapid and sensitive method for the quantitation of microgram quantities of protein utilizing the principle of protein-dye bindingAnalytical Biochemistry, 1976