Relations of morphometric parameters to zinc content in paediatric and nonhyperplastic young adult prostate glands

To clarify age-related histological and zinc content changes in paediatric and nonhyperplastic young adult prostate glands, a quantitative morphometric and energy-dispersive X-ray fluorescence analysis (EDXRF) was performed. The prostates were obtained at autopsy from 50 subjects (European-Caucasian aged 0-30 years) who died from sudden infant death syndrome, acute pulmonary aetiologies and trauma. None of the subjects had any symptoms of prostatic disease and all prostates were classified as histologically normal. Each prostate was divided into two portions. One tissue portion was reviewed by an anatomical pathologist whereas another was intended for a Zn mass fraction measurement using EDXRF. The mean per cent volume of the stroma (S), glandular epithelium (E), glandular lumen (L) and glandular component (GC = E + L) were determined and the mean ratios of per cent volumes (S/E, S/GC and E/L) were calculated for each prostate specimen. It was found that normal prostate tissue undergoes substantial changes from birth through early adulthood. These changes are reflected in an increment of the per cent volume of the glandular epithelium and lumen and in a diminution of the per cent volume of the stroma. The S/E ratio of the prostate falls by a factor of almost 4, between ages <1 and 30 years from 5 : 1 to 1.3 : 1. The Zn mass fraction is nearly 30-35 mg/kg (wet weight basis) and remains steady for first decade of life. Then it begins to increase rapidly during and after puberty. The level of the Zn content in prostate tissue is most closely associated with the volume of the glandular lumen, which reflects the volume of prostatic fluid.