Regulation of vascular permeability in rat testes by modified human chorionic gonadotrophin.

High-performance liquid (HPL)-anion-exchange chromatography of testicular interstitial fluid (IF) and medium conditioned by polymorphonuclear leucocytes (PMN) revealed two major peaks (at fractions 2-3 and 7-8), which, with human chorionic gonadotrophin (hCG) increased vasopermeability in rat testes measured by the uptake of iodinated hCG and by interstitial fluid volume. When hCG was incubated with the fraction 7-8 peak and subsequently purified on HPLC it significantly increased testicular vasopermeability with a concomitant accumulation of PMNs in the testicular blood vessels and interstitium. The removal of hCG from the purified preparation with anti-hCG Sepharose 4B abolished the vasopermeability effect of the preparation, confirming that hCG itself is modified in such a way as to produce the response. The results suggest that both IF and PMN-conditioned medium contain two components with different charges, which interact with hCG to increase vasopermeability by a PMN-mediated process. The results also indicated that hCG may itself be modified chemotactically, or so that it elicits production of leucoattractant in the testes.