Portal de Periódicos da CAPES

Evidence that changes in LH pulse frequency may regulate the seasonal modulation of LH secretion in ovariectomized mares

1983; Bioscientifica; Volume: 69; Issue: 2 Linguagem: Inglês

10.1530/jrf.0.0690685

1741-7899

B. P. Fitzgerald, Helen I’Anson, R. G. Loy, Sandra J. Legan,

Veterinary Equine Medical Research

Summary. To determine whether tonic LH secretion in ovariectomized mares is characterized by pulsatile release, frequent blood samples (every 15 min) were collected from 5 ovariectomized horse mares in nine 8-h periods between February and May. Mean serum LH concentrations increased 9-fold and were associated with a 4-fold increase in mean LH pulse frequency. These results provide the first evidence of pulsatile LH release in ovariectomized mares and suggest that the increasing daylengths of the spring months may increase serum LH by increasing LH pulse frequency.