Related Experiment Videos
Expression of prolactin receptor mRNA is increased in the preoptic area of lactating rats
1Department of Anatomy and Structural Biology, School of Medical Sciences and Neuroscience Research Centre, University of Otago, Dunedin, New Zealand.
Abstract:
This study investigated expression of prolactin receptor (PRL-R) mRNA in the preoptic area in midlactating rats compared with diestrous rats. Tissues from specific nuclei were micropunched from 300-microm thick rat brain sections with 300- or 500-microm diameter needles. After total RNA was extracted, the two forms of PRL-R mRNA were evaluated by reverse transcriptase polymerase chain reaction and Southern hybridization. The results showed that levels of long-form PRL-R mRNA in the ventrolateral preoptic nucleus and lateroanterior nucleus in lactating rats were significantly higher (p < 0.05) than in diestrous rats. The ventromedial and medial preoptic nuclei in lactating rats also expressed moderately high levels of long-form mRNA when compared with (p = 0.0547) diestrous rats. The ventromedial and ventrolateral preoptic nuclei, and ventrolateral hypothalamic nucleus in lactating rats expressed significantly higher levels of short-form mRNA than in diestrous rats. The increased expression of both forms of PRL-R mRNA helps explain numerous effects of PRL on brain functions during lactation.
Insights
Prolactin receptor (PRL-R) mRNA expression increased in specific brain regions of lactating rats compared to non-lactating rats. This finding helps explain prolactin
Area of Science:
- Neuroendocrinology
- Molecular Biology
- Reproductive Biology
Background:
- Prolactin (PRL) influences numerous brain functions, particularly during lactation.
- The prolactin receptor (PRL-R) mediates PRL's effects in the brain.
- Understanding PRL-R mRNA expression in specific brain nuclei is crucial for elucidating PRL's neurobiological roles.
Purpose of the Study:
- To investigate the expression levels of both long-form and short-form prolactin receptor (PRL-R) mRNA in the preoptic area of midlactating rats versus diestrous rats.
- To determine if PRL-R mRNA expression differs between lactating and non-lactating physiological states.
Main Methods:
- Micropunch technique was used to isolate specific brain nuclei from rat brain sections.
- Total RNA was extracted from isolated tissues.
- Reverse transcriptase polymerase chain reaction (RT-PCR) and Southern hybridization were employed to quantify PRL-R mRNA levels.
Main Results:
- Significantly higher levels of long-form PRL-R mRNA were observed in the ventrolateral preoptic nucleus and lateroanterior nucleus of lactating rats compared to diestrous rats (p < 0.05).
- Moderately high levels of long-form PRL-R mRNA were also found in the ventromedial and medial preoptic nuclei of lactating rats.
- Significantly higher levels of short-form PRL-R mRNA were detected in the ventromedial and ventrolateral preoptic nuclei, and ventrolateral hypothalamic nucleus of lactating rats compared to diestrous rats.
Conclusions:
- Lactation is associated with increased expression of both long-form and short-form PRL-R mRNA in specific preoptic area nuclei.
- These changes in PRL-R mRNA expression likely contribute to the known effects of prolactin on brain functions during the lactating period.
- The findings provide molecular insights into the neuroendocrine regulation of maternal behavior and physiology.