We have studied the direct effect of leptin on the secretion of GH from the anterior pituitary gland of the sheep. Using primary cultures of ovine pituitary cells, leptin (10-9-10-7 M) treatment for 30 min did not affect basal or GHRH (10-7 M)-stimulated GH secretion. Following treatment for 24 h, a dose of 10-7 M leptin stimulated basal GH secretion. In contrast, doses of 10-7 and 10-8 M leptin inhibited GHRH-stimulated GH secretion after 24 h of treatment. These results suggest that leptin can have long-term effects on the somatotropes, but no acute effect. Furthermore, leptin appears to have opposite effects on basal and GHRH-stimulated GH secretion.
- Growth hormone
- Growth hormone-releasing hormone
ASJC Scopus subject areas
- Endocrinology, Diabetes and Metabolism
- Endocrine and Autonomic Systems
- Cellular and Molecular Neuroscience