Prolactin mRNA exists in rat hypothalamus

Area of Science:

• Neuroendocrinology
• Molecular Biology
• Genetics

Background:

• Prolactin (PRL) is a key hormone primarily produced by the pituitary gland.
• The potential synthesis of PRL within the brain, specifically the hypothalamus, has been a subject of investigation.

Purpose of the Study:

• To investigate the presence and characteristics of prolactin mRNA in rat brain tissues.
• To determine if the rat brain, particularly the hypothalamus, synthesizes PRL.

Main Methods:

• Utilized radiolabeled complementary DNA (cDNA) probes specific to rat pituitary prolactin mRNA.
• Performed RNA gel blot analysis on RNA extracted from rat pituitary, hypothalamus, and liver tissues.
• Analyzed poly (A)-enriched RNA from male and female hypothalami.

Main Results:

• Detected a hybridizable RNA in both male and female hypothalami.
• The hypothalamic RNA exhibited the same size as mature pituitary PRL mRNA.
• This RNA was less abundant in the hypothalamus compared to the pituitary.

Conclusions:

• The presence of pituitary-like PRL mRNA in the hypothalamus supports the hypothesis of brain-derived prolactin synthesis.
• These findings suggest the rat brain may be a site for PRL production, in addition to the pituitary gland.