title: Relationship between plasma growth hormone concentration and cellular sodium transport in acromegaly.
abstract: We investigated the relationship between mean plasma growth hormone (GH) concentration and cellular sodium transport in untreated and treated acromegaly. Seventeen patients (age 55 +/- 3 years) with active acromegaly were studied with respect to plasma GH (mean of 24 h GH profile) and erythrocyte electrolyte content as well as transmembrane sodium transport. The patients were reinvestigated two weeks after successful surgery (N = 14) and again after one year (N = 13). Erythrocyte electrolytes were analyzed by flame photometry and sodium influx and efflux rate constant determined by in vitro incubation using a modified Keyne's formula. In patients with active acromegaly there was a significant positive correlation between IGF-1 and cellular sodium transport, while GH tended to show a negative relationship to the same parameter. After successful treatment, both IGF-1 and GH disclosed a positive relationship to cellular sodium transport. After one year, a significant increase in erythrocyte sodium content was seen in the patients compared to the preoperative situation. In conclusion, if this is a generalized phenomenon the results are compatible with a sodium-retaining effect of GH via stimulation of transmembrane sodium transport. In active acromegaly this may be counteracted by a sodium transport inhibitor giving the reverse relationship between GH and cellular sodium transport.
authors.affiliation: Department of Nephrology, University of Göteborg, Sweden.
authors.forename: H
authors.initials: H
authors.lastname: Herlitz
authors.forename: O
authors.initials: O
authors.lastname: Jonsson
authors.forename: B A
authors.initials: BA
authors.lastname: Bengtsson
mesh_terms: D000172:Acromegaly / Q000378:metabolism*; D000328:Adult; D000368:Aged; D001692:Biological Transport / Q000502:physiology; D004912:Erythrocytes / Q000378:metabolism / Q000502:physiology; D005260:Female; D013006:Growth Hormone / Q000097:blood* / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D008954:Models, Biological; D010783:Photometry / Q000379:methods; D012964:Sodium / Q000493:pharmacokinetics*
chemical_list: D013006:Growth Hormone; D012964:Sodium