Effects of hypochlorous acid and ascorbic acid on conductance, permeability, and structure of equine colonic mucosa in vitro.

The research investigates the impact of hypochlorous acid (HOCl) on horse’s colon cells and assesses if ascorbic acid can protect these cells. It concludes that low concentrations of HOCl can change electrical current, possibly increasing secretions, but higher levels can harm the tissue. Adding ascorbic acid can prevent these changes.

Study Methodology

• The in vitro experiment involved six healthy horses and ponies, with their colonic mucosa being the focus of the research.
• The colonic mucosa was placed in Ussing chambers, which allow for the measurement of electrical changes in tissue in order to determine its permeability and health.
• Different combinations and concentrations of hypochlorous acid and ascorbic acid were applied to the tissue and examined.
• The effects were measured using a short-circuit current, a method of measuring ion movement across a cell membrane. In addition, permeability changes were evaluated using mannitol – a type of sugar alcohol.
• At the end of each experiment, the tissues were examined under a microscope to visually assess the impacts of the chemicals.

Research Findings

• Low concentration (1 mM) of HOCl increased the short-circuit current and positively affected tissue conductance. Although this concentration caused mild damage to surface cells, these effects could be nullified with the addition of ascorbic acid (5 mM).
• Higher HOCl concentrations (3 and 7 mM) significantly increased conductance, current, and mannitol permeability indicating a higher level of tissue damage. Co-incubation with ascorbic acid shielded against these changes exhibiting its protective nature.
• The results suggested that the observed effects of HOCl and the protective aspects of ascorbic acid were not due to pH changes.

Conclusions

• The research concludes that HOCl, at low concentrations, can elevate the short-circuit current in equine colon, possibly amplifying secretions. However, higher concentrations may result in tissue damage.
• The researchers also noted that ascorbic acid, at 5 mM concentration, can safeguard against these changes.
• The damage caused by HOCl concentrations found in activated neutrophils could potentially lead to, or contribute to, reperfusion injury – a type of tissue damage caused when blood returns to tissue after a period of ischemia or lack of oxygen.
• The study indicates the potential of ascorbic acid in mitigating this injury and suggests the possibility of a pharmaceutical approach to treating this particular type of injury.