Relationship between Release of LH and Incorporation of Tritiated Thymidine in the Anterior Pituitary Gland of the Castrated Female Rat

Summary

Castration of female rats during diestrus increases the concentration of circulating LH from days 3 and the incorporation of ³H thymidine into pituitary DNA from day 5. Both effects are completely abolished by the administration of dihydrotestosterone.

Although the i.v. injection of LHRH markedly enhances the concentration of LH in serum, it does not modify the incorporation of ³H thymidine into pituitary DNA.

Castration might produce a maximal stimulation in ³H thymidine incorporation and a further stimulation of LH release with LHRH is unable to enhance the incorporation of the radioactive precursor.

The results suggest a relationship between LH secretion and DNA synthesis in the pituitary gland of the rat.

Key-Words:

Pituitary Gland - Castration - LH Secretion - DNA Synthesis