CATION CONTENT AND FLUXES IN RED CELLS OF NORMAL AND HYFERTENSIVE NIGERIANS

ABSTRACT

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FLUXES IN NORMAL aND HYPERTENSIVE NIGERIANS

RED CELL SODIUM AND POTASSIUM CONTENT AF

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luts in Ni

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Nigerians .gerians with known

1. Erythrocyte sodium, potassium and water content have been determined in 908 Nigfferians so as to:

1. establish normal va!

2. compare values ^ values in other blacks.

3. compare va itSe> in Nigerians with those of caucasians.

Red cell s^Üfum, potassium and water were also

deterrrrined in 7 caucasians who had been resident i

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igeria for periods varying from 6 mnnths to 18 years. The RBC sodium for Nigerians considerably

higher than those of caucasians, but the RBC ^^kitassium and water öi(l not show any significant difference.

In the course of this work, the normal (control) subjects were grouped according to their genotypes.

3 genotypes were encountered: AA, AS and AC.

There was no significant difference in the erythrocyte sodium, potassium and water of the individuals belonging to these 3 genotypes.

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The results wäre also analysed for sex and age differences, and none was fcund.

Results of erythrocyte sodium, pot^ssium

wa

potassium and ter from 3 siblings and their mother were also

presc.nted. These results differed, from one another,

suggesting that environmental faotors are also important and probably just^^potent determinants of RBC sodium, potassium and water content as are genetic factcrs.

2. 100 hypertensi^: subjects were studied. They

were all n^wly diagnosed, mostly symptomless it subjcdt

ambulant sU^^ects who were attending the medical

out-patient department of the University College Hospital, Ibadan. Their main pathological finding

systemic hypertension. They were followed up

4ör periods varying from 18 months to 3h years. Investigations were performed on each patxent which enabled their being grouped into hypertensives with normal renal function or hypertensives with abnormal renal function. Only those with normal renal function were included in the study.

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The results obtained for the red cell sodium

and potassium were significantly different from those of the Controls. Their red cell water was also significantly different from that of the Controls, but the difference m RBC wa

ter was not

sufficient to account for the differences in the RBC sodium and potassium.

Here again, the RBC sodxum and potassium were not related tc age or sex. The R3C sodium and potassium content were. in no wa*y related to the tneao bioöd pressures. Their values remained the same both befere and du^ino treatmcnt. Adequate control and maintenance of the patients blood pressures within th£ normal ränge üid not nffect these two cations.

3. Wien red cells from Controls and red cells from Hypertensives tutre exposed to n high sodium load, the I^BCs from hypertensive gaine-dtvlot more sodium and lost a lot more potassium than the RBCs from Controls.

4. Normal red cells lost their potassium into isotonic sucrose media seven times as fast as red cells from hypertensive subjects.

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5. Normal red cells have a slightly higher aative. sodium flux per hour than red cells from hypertensive subjects, but the difference is not statistically significant.

The rate constant for active sodium flux is

Statist

higher for red cells of Controls than for red cells of hypertensive subjects, but the correlation

between intracellular sodium/content and rate

,43)» The rate constant for the red cells of the hypertensives is lower, but it correlates better with the red cell sodium (r =0*53)»