SciELO - Scientific Electronic Library Online

 
vol.7 número1Curvas de lactancia individuales en vacas Siboney de CubaEstudio morfométrico de los epidídimos durante el desarrollo postnatal de corderos Barbados Blackbelly índice de autoresíndice de materiabúsqueda de artículos
Home Pagelista alfabética de revistas  

Servicios Personalizados

Revista

Articulo

Indicadores

Links relacionados

  • No hay artículos similaresSimilares en SciELO

Compartir


Revista mexicana de ciencias pecuarias

versión On-line ISSN 2448-6698versión impresa ISSN 2007-1124

Resumen

ORTEGA, Álvaro et al. Biological and immunological activity in bovine luteinizing hormone charge isoforms. Rev. mex. de cienc. pecuarias [online]. 2016, vol.7, n.1, pp.29-51. ISSN 2448-6698.

Luteinizing hormone (LH) undergoes posttranslational modifications that originate different charge isoforms. The study evaluated the differences in biological (B) and immunological (I) activity between isoforms of bovine LH. Isoforms were isolated by chromatofocusing from anterior pituitary glycoprotein extract. The biological activity was evaluated in an in vitro bioassay. Immunological activity was measured with a radioimmunoassay (RIA) specific for LH. The USDA-bLH-B5 standard was utilized as the reference. LH isoforms were grouped by their pH range of elution, in basic (A, pH, 10.75-9.75; B, pH 9.58-8.41), neutral (C pH, 7.98-6.89) and acidic (D, pH, 6.88-5.41; E, pH 5.36-3.46). The molecular weight of the heterodimer of each isoform was similar to the LH standard, estimated to be 36.5 kDa. Immunological and biological activity behaved in a dose-dependent manner. With respect to the LH standard, all isoforms required higher protein concentration to reach the IC50 of the inhibition curve. In the bioassay EC50 value for cAMP production was significantly different among isoforms; the neutral isoform showed a lower EC50 which was interpreted as more bioactive, the acidic isoform E showed an EC50 being the least bioactive and the basic was intermediate (P<0.05). In conclusion, the results suggest a quantitative effect of LH charge isoforms on the cAMP production, per unit of immunoreactive LH in the bioassay.

Palabras llave : Luteinizing hormone; Biological activity; Immunological activity.

        · resumen en Español     · texto en Español | Inglés     · Español ( pdf ) | Inglés ( pdf )