The magnitude of growth hormone elevation is related with the proportion of monomeric form in acromegaly.
In acromegalic patients monomeric GH form constitutes the larger proportion of circulating GH; however, no data are available concerning the relation between total GH elevation and the predominance of GH forms. Therefore, we studied the relationship between the degree of GH elevation and the proportion of GH isoforms. Sera from 11 patients with active acromegaly were subjected to gel chromatography on Sephadex G-100 column and fractions were collected for RIA to measure GH. The monomeric form of GH was predominant and exhibited a lineal correlation (r = 0.76, p < 0.01) with the circulating GH, thus the higher elevation of GH, the major proportion of monomeric GH. IGF-1 changes correlate with changes in monomeric GH but no better than for total GH. There was a correlation observed (r = 0.65) between the proportion of low GH forms and the presence of hyperglycemia, although the physiological role of the lower molecular GH forms is still unknown. In conclusion, it was demonstrated that the relative proportion of GH molecular forms changes according to the magnitude of the elevation of total GH.
Ochoa
R
R
Unidad de Investigación en Enfermedades Endócrinas, Hospital de Especialidades, Centro Médico Nacional Siglo XXI, Instituto Mexicano del Seguro Social, México, D.F.
Fonseca
E
E
Mercado
M
M
Galván
R E
RE
Hernández
M
M
Zárate
A
A
D000172:Acromegaly / Q000097:blood*; D000328:Adult; D016022:Case-Control Studies; D005260:Female; D013006:Growth Hormone / Q000097:blood* / Q000737:chemistry; D006801:Humans; D008297:Male; D008875:Middle Aged; D008970:Molecular Weight
D013006:Growth Hormone