Immunolocalization of Leptin and its Receptor (ObR-b) in Equine Placenta at Term and Plasma Level Measurement in the Late Gestation.

The study examined the presence and distribution of leptin and its receptor (ObR-b) in the placenta of horses at the end of their pregnancy term. The study furthermore noted the changes in plasma leptin concentrations during the late pregnancy stage. This study is contributing to prevalent knowledge with unique insights specific to horses.

Research Methodology

• The sample of the study comprised of eight pregnant Criollo-type mares, specifically chosen as they were carrying healthy pregnancies.
• Blood samples were taken during the final trimester of pregnancy, immediately after giving birth, and 24 hours post-birth.
• The concentrations of leptin present in the collected samples were analyzed using a process known as radioimmunoassay.
• The presence and the dispersion of leptin and its receptor, ObR-b in the equine placenta was studied using a technique of immunofluorescence staining.

Key Findings

• The analysis revealed that plasma leptin concentrations remained consistent from the 8th to the 10th month of gestation but showed a slight decrease 24 hours after parturition.
• The study further discovered leptin and ObR-b in the cytoplasm of certain cells in the areolar region and the epithelium of microcotyledons in the placenta. In addition, leptin receptors were located on the cell’s apical surface.

Study Implications

• The existence of Leptin and its receptor ObR-b in the placenta indicates that Leptin likely has both an endocrine function (that is, it is secreted into the bloodstream and transported to the tissues and organs that it affects) and an autocrine/paracrine function (meaning it acts on cells in the immediate vicinity).
• This discovery establishes important groundwork for future research into the role Leptin plays in the placenta at the term of equine pregnancy.