Immunoreactive relaxin-like substance in human seminal plasma

Area of Science:

• Reproductive Endocrinology
• Andrology
• Biochemistry

Background:

• Relaxin, a peptide hormone, plays roles in reproduction and tissue remodeling.
• Its presence and function in male reproductive fluids, specifically seminal plasma, are not fully understood.
• Investigating novel peptides in seminal plasma is crucial for understanding male fertility.

Purpose of the Study:

• To quantify the concentration of immunoreactive relaxin-like peptide in human seminal plasma.
• To assess the variability of this peptide in healthy volunteers and infertile males.
• To validate the radioimmunoassay (RIA) method for accurate measurement in the complex seminal plasma matrix.

Main Methods:

• Radioimmunoassay (RIA) was employed to detect and quantify the relaxin-like peptide.
• Samples were collected from seven healthy male volunteers and twenty-eight non-selected male patients presenting with sterility.
• Assay validity was critically evaluated for the specific conditions of seminal plasma.

Main Results:

• Significant amounts of an immunoreactive relaxin-like peptide were detected in human seminal plasma.
• Concentrations varied widely, ranging from 1,240 pg to 73,000 pg of relaxin porcine equivalents per ml.
• The RIA system demonstrated acceptable validity for measuring the peptide in seminal plasma.

Conclusions:

• Human seminal plasma contains a relaxin-like peptide at substantial concentrations.
• The peptide concentration exhibits considerable inter-individual variability.
• Further research is warranted to elucidate the physiological role of this peptide in male reproductive function and fertility.