Hypothalamic growth hormone-releasing hormone mRNA varies across the day in rats
Generate an AI Snapshot to get a quick, structured summary of this paper.
A concise AI-generated summary of the paper will appear here once you click Generate AI Snapshot.
TL;DR
The results demonstrate that hypothalamic GHRH mRNA displays diurnal variations, and beta-Actin mRNA expression in the cortex was higher in the dark than in the light period.
Abstract
Experiments were performed to determine whether growth hormone-releasing hormone (GHRH) mRNA displays diurnal variations in the hypothalamus and cortex of the rat. Levels of GHRH and beta-actin mRNA were measured from hypothalamic and cortical extracts using the reverse transcriptase polymerase chain reaction method in rats sacrificed at 4 h intervals across a 12:12 h light:dark cycle. Hypothalamic GHRH mRNA peaked around the light onset, declined during the light period, and stayed low in the dark. Variations in hypothalamic beta-actin and cortical GHRH mRNA levels were not observed. beta-Actin mRNA expression in the cortex was higher in the dark than in the light period. The results demonstrate that hypothalamic GHRH mRNA displays diurnal variations.